diff --git a/.github/workflows/dart_ci.yml b/.github/workflows/dart_ci.yml
index 745cebcfc..5fb6c84f0 100644
--- a/.github/workflows/dart_ci.yml
+++ b/.github/workflows/dart_ci.yml
@@ -16,9 +16,7 @@ jobs:
       fail-fast: false
       matrix:
         # Can't run on `dev` (Dart 3) until we're fully null-safe.
-        # We can't run on Dart >=2.19 until https://github.com/dart-lang/sdk/issues/51128
-        # is fixed, or we work around it, which requires upgrading to analyzer ^5.1.0.
-        sdk: [ 2.13.4, 2.18.7 ]
+        sdk: [ 2.18.7, 2.19.6 ]
     steps:
       - uses: actions/checkout@v2
       - uses: dart-lang/setup-dart@v0.2
@@ -88,16 +86,11 @@ jobs:
       fail-fast: false
       matrix:
         # Can't run on `dev` (Dart 3) until we're fully null-safe.
-        # We can't run on Dart >=2.19 until https://github.com/dart-lang/sdk/issues/51128
-        # is fixed, or we work around it, which requires upgrading to analyzer ^5.1.0.
-        sdk: [ 2.13.4, 2.18.7 ]
+        sdk: [ 2.18.7, 2.19.6 ]
         analyzer:
-          - ^1.0.0
-          - ^2.0.0
-        # Don't validate analyzer ^2.0.0 in 2.13.4 since it can't resolve.
-        exclude:
-          - sdk: 2.13.4
-            analyzer: ^2.0.0
+          # We only have one version currently, but we'll leave this CI step in place
+          # for the next time we need to support multiple analyzer versions.
+          - ^5.1.0
     steps:
       - uses: actions/checkout@v2
       - uses: dart-lang/setup-dart@v0.2
diff --git a/.gitignore b/.gitignore
index c70d3dfb0..095463ceb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -45,3 +45,6 @@ pubspec.lock
 
 # Should not track the output of code coverage for now
 coverage/
+
+tools/analyzer_plugin/test/test_fixtures/**/lib/dynamic_test_files/
+tools/analyzer_plugin/test/temporary_test_fixtures/**
diff --git a/Dockerfile b/Dockerfile
index a89342ca1..6146f797a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM google/dart:2.13
+FROM dart:2.18
 
 # Expose env vars for git ssh access
 ARG GIT_SSH_KEY
diff --git a/app/over_react_redux/todo_client/pubspec.yaml b/app/over_react_redux/todo_client/pubspec.yaml
index 6c2ebede4..1b4556607 100644
--- a/app/over_react_redux/todo_client/pubspec.yaml
+++ b/app/over_react_redux/todo_client/pubspec.yaml
@@ -26,7 +26,7 @@ dev_dependencies:
   test: ^1.15.7
   test_html_builder: ^3.0.0
   time: ^1.2.0
-  w_common: '>=2.0.0 <4.0.0'
+  w_common: ^3.0.0
   workiva_analysis_options: ^1.1.0
 
 dependency_overrides:
diff --git a/lib/src/builder/codegen/accessors_generator.dart b/lib/src/builder/codegen/accessors_generator.dart
index 2849191e7..162bd966c 100644
--- a/lib/src/builder/codegen/accessors_generator.dart
+++ b/lib/src/builder/codegen/accessors_generator.dart
@@ -54,7 +54,7 @@ abstract class TypedMapAccessorsGenerator extends BoilerplateDeclarationGenerato
 
   String get accessorsMixinName;
 
-  ClassOrMixinDeclaration get node => member.node as ClassOrMixinDeclaration;
+  ClassishDeclaration get node => member.node.asClassish();
 
   TypeParameterList get typeParameters => member.nodeHelper.typeParameters;
 
@@ -363,7 +363,9 @@ class _TypedMapMixinAccessorsGenerator extends TypedMapAccessorsGenerator {
 
   @override
   void generate() {
-    outputContentsBuffer..write(_generateAccessorsMixin())..write(_generateMetaConstImpl());
+    outputContentsBuffer
+      ..write(_generateAccessorsMixin())
+      ..write(_generateMetaConstImpl());
   }
 }
 
@@ -422,9 +424,8 @@ class _LegacyTypedMapAccessorsGenerator extends TypedMapAccessorsGenerator {
       return '';
     }
 
-    final classishNode = node.asClassish();
-    final metadata = classishNode.metadata;
-    final typeParameters = classishNode.typeParameters;
+    final metadata = node.metadata;
+    final typeParameters = node.typeParameters;
     final typeParamsOnClass = typeParameters?.toSource() ?? '';
     final typeParamsOnSuper = removeBoundsFromTypeParameters(typeParameters);
     final accessorsMixinName = names.legacyAccessorsMixinName;
@@ -462,7 +463,7 @@ class TypedMapType {
   static const TypedMapType stateMixin = TypedMapType(false, false, true);
 }
 
-String _copyClassMembers(ClassOrMixinDeclaration node) {
+String _copyClassMembers(ClassishDeclaration node) {
   bool isValidForCopying(ClassMember member) {
     // Static members should be copied over as needed by [_copyStaticMembers].
     // Otherwise, fields which are not synthetic have concrete getters/setters
@@ -493,7 +494,7 @@ String _copyClassMembers(ClassOrMixinDeclaration node) {
   return buffer.toString();
 }
 
-String _copyStaticMembers(ClassOrMixinDeclaration node) {
+String _copyStaticMembers(ClassishDeclaration node) {
   final buffer = StringBuffer();
   node.members.where(isStaticMember).forEach((member) {
     // Don't copy over anything named `meta`, since the static meta field is already going to be generated.
diff --git a/lib/src/builder/codegen/component_factory_generator.dart b/lib/src/builder/codegen/component_factory_generator.dart
index 32d1bad74..a055e7940 100644
--- a/lib/src/builder/codegen/component_factory_generator.dart
+++ b/lib/src/builder/codegen/component_factory_generator.dart
@@ -100,6 +100,8 @@ class ComponentFactoryProxyGenerator extends BoilerplateDeclarationGenerator {
       outputContentsBuffer.writeln('    skipMethods: const [],');
     }
 
-    outputContentsBuffer..writeln(');')..writeln();
+    outputContentsBuffer
+      ..writeln(');')
+      ..writeln();
   }
 }
diff --git a/lib/src/builder/codegen/typed_map_impl_generator.dart b/lib/src/builder/codegen/typed_map_impl_generator.dart
index 936d25699..f0691bed3 100644
--- a/lib/src/builder/codegen/typed_map_impl_generator.dart
+++ b/lib/src/builder/codegen/typed_map_impl_generator.dart
@@ -133,7 +133,7 @@ abstract class TypedMapImplGenerator extends BoilerplateDeclarationGenerator {
   String _generateConcretePropsOrStateImpl({
     String componentFactoryName,
     String propKeyNamespace,
-    List<Identifier> allPropsMixins,
+    List<String> allPropsMixins,
   }) {
     if (isProps) {
       if (componentFactoryName == null || propKeyNamespace == null) {
@@ -153,7 +153,9 @@ abstract class TypedMapImplGenerator extends BoilerplateDeclarationGenerator {
       classDeclaration.write('abstract ');
     }
 
-    classDeclaration..write(_generateImplClassHeader())..write(' {');
+    classDeclaration
+      ..write(_generateImplClassHeader())
+      ..write(' {');
 
     final propsOrState = isProps ? 'props' : 'state';
 
@@ -235,7 +237,9 @@ abstract class TypedMapImplGenerator extends BoilerplateDeclarationGenerator {
     // Component2-specific classes
     if (isComponent2) {
       // TODO need to remove this workaround once https://github.com/dart-lang/sdk/issues/36217 is fixed get nice dart2js output
-      buffer..writeln()..writeln('''
+      buffer
+        ..writeln()
+        ..writeln('''
 // Concrete $propsOrState implementation that can be backed by any [Map].
 ${internalGeneratedMemberDeprecationLine()}class ${names.plainMapImplName}$typeParamsOnClass extends ${names.implName}$typeParamsOnSuper {
   // This initializer of `_$propsOrState` to an empty map, as well as the reassignment
@@ -350,7 +354,7 @@ class _TypedMapImplGenerator extends TypedMapImplGenerator {
   @override
   final Version version;
 
-  final List<Identifier> allPropsMixins;
+  final List<String> allPropsMixins;
 
   _TypedMapImplGenerator.props(ClassComponentDeclaration declaration)
       : names = TypedMapNames(declaration.props.either.name.name),
@@ -434,8 +438,9 @@ class _TypedMapImplGenerator extends TypedMapImplGenerator {
       return 'class ${names.implName}$typeParamsOnClass'
           ' extends ${isProps ? 'UiProps' : 'UiState'}'
           ' with\n'
-          ' ${names.consumerName}$typeParamsOnSuper\n,'
-          ' ${names.generatedMixinName}$typeParamsOnSuper${generatedMixinWarningCommentLine(names, isProps: isProps)}';
+          ' ${names.consumerName}$typeParamsOnSuper,\n'
+          ' ${generatedMixinWarningCommentLine(names, isProps: isProps)}'
+          ' ${names.generatedMixinName}$typeParamsOnSuper';
     } else if (member is BoilerplatePropsOrState) {
       final header = StringBuffer()
         ..write('class ${names.implName}$typeParamsOnClass'
@@ -462,14 +467,14 @@ class _TypedMapImplGenerator extends TypedMapImplGenerator {
           final names = TypedMapNames(mixin.name.name);
           header.write('${names.consumerName}$typeArguments');
           header.write(',');
+          // Add a space at the beginning of the line so that dartfmt indents it
+          // with the following line, as opposed to "sticking" it to the beginning of the line.
+          header.write('\n ' + generatedMixinWarningCommentLine(names, isProps: isProps));
           header.write('${names.generatedMixinName}$typeArguments');
           // Don't write the comma if we're at the end of the list.
-          // Do this manually instead of using `.join` so that we can always have
-          // the warning comment be at the end of the line, regardless of whether the comma is there.
           if (i != mixins.length - 1) {
             header.write(',');
           }
-          header.write(generatedMixinWarningCommentLine(names, isProps: isProps));
         }
       }
 
diff --git a/lib/src/builder/codegen/util.dart b/lib/src/builder/codegen/util.dart
index 143b41735..4d4681aaf 100644
--- a/lib/src/builder/codegen/util.dart
+++ b/lib/src/builder/codegen/util.dart
@@ -12,7 +12,6 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-import 'package:analyzer/dart/ast/ast.dart';
 import 'package:logging/logging.dart';
 import 'package:meta/meta.dart';
 import 'package:over_react/src/component_declaration/annotations.dart' as annotations;
@@ -70,7 +69,7 @@ String generatedMixinWarningCommentLine(TypedMapNames mixinNames, {@required boo
 
 void generatePropsMeta(
   StringBuffer buffer,
-  List<Identifier> mixins, {
+  List<String> mixins, {
   String classType = 'PropsMetaCollection',
   String fieldName = 'propsMeta',
 }) {
@@ -79,7 +78,7 @@ void generatePropsMeta(
     ..writeln('  @override')
     ..writeln('  $classType get $fieldName => const $classType({');
   for (final name in mixins) {
-    final names = TypedMapNames(name.name);
+    final names = TypedMapNames(name);
     buffer.write('    ${generatedMixinWarningCommentLine(names, isProps: true)}');
     buffer.writeln('    ${names.consumerName}: ${names.publicGeneratedMetaName},');
   }
diff --git a/lib/src/builder/parsing/ast_util.dart b/lib/src/builder/parsing/ast_util.dart
index d42475f9d..e787eae8f 100644
--- a/lib/src/builder/parsing/ast_util.dart
+++ b/lib/src/builder/parsing/ast_util.dart
@@ -93,8 +93,8 @@ extension SuperclassConstraint on MixinDeclaration {
   }
 }
 
-/// Utilities for determining if a [ClassOrMixinDeclaration] has an abstract getter.
-extension AbstractGetter on ClassOrMixinDeclaration {
+/// Utilities for determining if a declaration has an abstract getter.
+extension AbstractGetter on ClassishDeclaration {
   /// Returns whether this class/mixin contains an abstract getter with the provided [name]
   /// and a return type exactly matching [type]
   bool hasAbstractGetter(String type, String name) =>
@@ -106,6 +106,15 @@ extension AbstractGetter on ClassOrMixinDeclaration {
           member.returnType?.toSource() == type);
 }
 
+/// An extension that supports APIs that changed from [Identifier] to [Token],
+/// in order to cut down on diffs in the analyzer 5 upgrade (and subsequent
+/// merge conflicts with the null-safety branch.
+///
+/// TODO remove this and inline the [name] member.
+extension NameIdentifierTokenCompat on Token {
+  String get name => lexeme;
+}
+
 /// Utilities that provide for easier access to [AnnotatedNode] metadata.
 extension MetadataHelper on AnnotatedNode {
   // Annotations don't always parse as expected, so `.name` can also include the constructor
diff --git a/lib/src/builder/parsing/ast_util/classish.dart b/lib/src/builder/parsing/ast_util/classish.dart
index 86100f036..63b283a24 100644
--- a/lib/src/builder/parsing/ast_util/classish.dart
+++ b/lib/src/builder/parsing/ast_util/classish.dart
@@ -19,7 +19,8 @@ extension Classish on NamedCompilationUnitMember {
   ClassishDeclaration asClassish() => ClassishDeclaration(this);
 }
 
-/// Provides a common interface for [ClassOrMixinDeclaration] and [ClassTypeAlias].
+/// Provides a common interface for [ClassDeclaration], [MixinDeclaration],
+/// and [ClassTypeAlias].
 abstract class ClassishDeclaration {
   factory ClassishDeclaration(NamedCompilationUnitMember node) {
     if (node is ClassDeclaration) {
@@ -41,7 +42,7 @@ abstract class ClassishDeclaration {
   //
   // Shared
 
-  SimpleIdentifier get name => node.name;
+  Token get name => node.name;
   NodeList<Annotation> get metadata => node.metadata;
 
   TypeParameterList get typeParameters;
@@ -49,9 +50,9 @@ abstract class ClassishDeclaration {
   Token get classOrMixinKeyword;
 
   /// All interfaces used by this class, including mixin superclass constraints.
-  List<TypeName> get interfaces;
+  List<NamedType> get interfaces;
 
-  List<TypeName> get allSuperTypes => [
+  List<NamedType> get allSuperTypes => [
         ...interfaces,
         ...mixins,
         if (superclass != null) superclass,
@@ -63,25 +64,12 @@ abstract class ClassishDeclaration {
   WithClause get withClause;
   Token get abstractKeyword;
   bool get hasAbstractKeyword => abstractKeyword != null;
-  TypeName get superclass;
+  NamedType get superclass;
 
-  List<TypeName> get mixins => withClause?.mixinTypes ?? const [];
+  List<NamedType> get mixins => withClause?.mixinTypes ?? const [];
 }
 
-abstract class _ClassishClassOrMixin extends ClassishDeclaration {
-  _ClassishClassOrMixin._() : super._();
-
-  @override
-  ClassOrMixinDeclaration get node;
-
-  @override
-  List<ClassMember> get members => node.members;
-
-  @override
-  TypeParameterList get typeParameters => node.typeParameters;
-}
-
-class _ClassishClass extends _ClassishClassOrMixin {
+class _ClassishClass extends ClassishDeclaration {
   @override
   final ClassDeclaration node;
 
@@ -91,21 +79,27 @@ class _ClassishClass extends _ClassishClassOrMixin {
   Token get abstractKeyword => node.abstractKeyword;
 
   @override
-  List<TypeName> get interfaces => [
+  List<NamedType> get interfaces => [
         ...?node.implementsClause?.interfaces,
       ];
 
   @override
-  TypeName get superclass => node.extendsClause?.superclass;
+  NamedType get superclass => node.extendsClause?.superclass;
 
   @override
   WithClause get withClause => node.withClause;
 
   @override
   Token get classOrMixinKeyword => node.classKeyword;
+
+  @override
+  List<ClassMember> get members => node.members;
+
+  @override
+  TypeParameterList get typeParameters => node.typeParameters;
 }
 
-class _ClasssishMixin extends _ClassishClassOrMixin {
+class _ClasssishMixin extends ClassishDeclaration {
   @override
   final MixinDeclaration node;
 
@@ -118,16 +112,22 @@ class _ClasssishMixin extends _ClassishClassOrMixin {
   Token get classOrMixinKeyword => node.mixinKeyword;
 
   @override
-  List<TypeName> get interfaces => [
+  List<NamedType> get interfaces => [
         ...?node.implementsClause?.interfaces,
         ...?node.onClause?.superclassConstraints,
       ];
 
   @override
-  TypeName get superclass => null;
+  NamedType get superclass => null;
 
   @override
   WithClause get withClause => null;
+
+  @override
+  List<ClassMember> get members => node.members;
+
+  @override
+  TypeParameterList get typeParameters => node.typeParameters;
 }
 
 class _ClassishClassTypeAlias extends ClassishDeclaration {
@@ -146,7 +146,7 @@ class _ClassishClassTypeAlias extends ClassishDeclaration {
   List<ClassMember> get members => const [];
 
   @override
-  TypeName get superclass => node.superclass;
+  NamedType get superclass => node.superclass;
 
   @override
   TypeParameterList get typeParameters => node.typeParameters;
@@ -155,7 +155,7 @@ class _ClassishClassTypeAlias extends ClassishDeclaration {
   WithClause get withClause => node.withClause;
 
   @override
-  List<TypeName> get interfaces => [
+  List<NamedType> get interfaces => [
         ...?node.implementsClause?.interfaces,
       ];
 }
diff --git a/lib/src/builder/parsing/declarations.dart b/lib/src/builder/parsing/declarations.dart
index fed8ae3d7..c66dad2cd 100644
--- a/lib/src/builder/parsing/declarations.dart
+++ b/lib/src/builder/parsing/declarations.dart
@@ -188,7 +188,7 @@ mixin _TypedMapMixinShorthandDeclaration {
     final mixin = propsOrState.b;
     if (mixin == null) return;
 
-    bool isBadConstraint(TypeName constraint) {
+    bool isBadConstraint(NamedType constraint) {
       final name = constraint.nameWithoutPrefix;
       return name != helpers.propsOrStateBaseClassString &&
           helpers.propsOrStateMixinNamePattern.hasMatch(name);
@@ -226,9 +226,9 @@ extension on Union<BoilerplateProps, BoilerplatePropsMixin> {
   ///
   /// This is the safest way to retrieve that information because it takes
   /// into account the nature of the [Union] typing of `props`.
-  List<Identifier> get allPropsMixins => this.switchCase(
-        (a) => a.nodeHelper.mixins.map((name) => name.name).toList(),
-        (b) => [b.name],
+  List<String> get allPropsMixins => this.switchCase(
+        (a) => a.nodeHelper.mixins.map((name) => name.name.name).toList(),
+        (b) => [b.name.name],
       );
 }
 
@@ -249,7 +249,7 @@ class ClassComponentDeclaration extends BoilerplateDeclaration
   @override
   get type => DeclarationType.classComponentDeclaration;
 
-  List<Identifier> get allPropsMixins => props.allPropsMixins;
+  List<String> get allPropsMixins => props.allPropsMixins;
 
   @override
   void validate(ErrorCollector errorCollector) {
@@ -285,7 +285,7 @@ class PropsMapViewOrFunctionComponentDeclaration extends BoilerplateDeclaration
   /// Can be either [BoilerplateProps] or [BoilerplatePropsMixin], but not both.
   final Union<BoilerplateProps, BoilerplatePropsMixin> props;
 
-  List<Identifier> get allPropsMixins => props.allPropsMixins;
+  List<String> get allPropsMixins => props.allPropsMixins;
 
   @override
   get _members => [...factories, props.either];
diff --git a/lib/src/builder/parsing/members.dart b/lib/src/builder/parsing/members.dart
index f8c843d35..1e2c49828 100644
--- a/lib/src/builder/parsing/members.dart
+++ b/lib/src/builder/parsing/members.dart
@@ -13,6 +13,8 @@
 // limitations under the License.
 
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
+import 'package:collection/collection.dart';
 import 'package:meta/meta.dart';
 import 'package:over_react/src/builder/codegen/names.dart';
 import 'package:over_react/src/component_declaration/annotations.dart' as annotations;
@@ -58,7 +60,7 @@ abstract class BoilerplateMember {
   /// given version.
   void validate(Version version, ErrorCollector errorCollector);
 
-  SimpleIdentifier get name;
+  Token get name;
 
   @override
   String toString() => '$runtimeType: ${name.name}';
diff --git a/lib/src/builder/parsing/members/component.dart b/lib/src/builder/parsing/members/component.dart
index 2a2b8d64a..2f8b84277 100644
--- a/lib/src/builder/parsing/members/component.dart
+++ b/lib/src/builder/parsing/members/component.dart
@@ -32,7 +32,7 @@ class BoilerplateComponent extends BoilerplateMember {
   final NamedCompilationUnitMember node;
 
   @override
-  SimpleIdentifier get name => nodeHelper.name;
+  Token get name => nodeHelper.name;
 
   /// A metadata class that lifts helpful fields out of [node] to a top level,
   /// in addition to providing additional getters relevant member parsing.
@@ -119,15 +119,16 @@ class BoilerplateComponent extends BoilerplateMember {
     });
 
     // Ensure that Component2 declarations do not use legacy lifecycle methods.
-    if (isComponent2(version) && node is ClassOrMixinDeclaration) {
+    if (isComponent2(version)) {
       Map<String, String> legacyLifecycleMethodsMap = {
         'componentWillReceiveProps': 'Use getDerivedStateFromProps instead.',
         'componentWillMount': 'Use componentDidMount instead.',
         'componentWillUpdate': 'Use getSnapshotBeforeUpdate and/or componentDidUpdate instead.',
       };
 
+      final methods = nodeHelper.members.whereType<MethodDeclaration>().toList();
       legacyLifecycleMethodsMap.forEach((methodName, helpMessage) {
-        final method = (node as ClassOrMixinDeclaration).getMethod(methodName);
+        final method = methods.firstWhereOrNull((m) => m.name.name == methodName);
         if (method != null) {
           errorCollector.addError(unindent('''
                When using Component2, a class cannot use ${method.name} because React 16 has removed ${method.name} 
diff --git a/lib/src/builder/parsing/members/factory.dart b/lib/src/builder/parsing/members/factory.dart
index d7053f3b7..79a3290b8 100644
--- a/lib/src/builder/parsing/members/factory.dart
+++ b/lib/src/builder/parsing/members/factory.dart
@@ -23,7 +23,7 @@ class BoilerplateFactory extends BoilerplateMember {
   final TopLevelVariableDeclaration node;
 
   @override
-  SimpleIdentifier get name => node.firstVariable.name;
+  Token get name => node.firstVariable.name;
 
   @override
   annotations.Factory get meta => const annotations.Factory();
diff --git a/lib/src/builder/parsing/members/props_and_state.dart b/lib/src/builder/parsing/members/props_and_state.dart
index 68572d8b2..4f6f36249 100644
--- a/lib/src/builder/parsing/members/props_and_state.dart
+++ b/lib/src/builder/parsing/members/props_and_state.dart
@@ -47,7 +47,7 @@ abstract class BoilerplatePropsOrState extends BoilerplateTypedMapMember
   annotations.TypedMap meta;
 
   @override
-  SimpleIdentifier get name => nodeHelper.name;
+  Token get name => nodeHelper.name;
 
   @override
   String get debugString => '${super.debugString}, companion: ${companion?.name}';
@@ -110,15 +110,13 @@ abstract class BoilerplatePropsOrState extends BoilerplateTypedMapMember
         break;
       case Version.v3_legacyDart2Only:
         _sharedLegacyValidation(errorCollector);
-        if (node is ClassOrMixinDeclaration) {
-          checkForMetaPresence(node as ClassOrMixinDeclaration, errorCollector);
-        }
+        checkForMetaPresence(nodeHelper, errorCollector);
         break;
     }
   }
 
   void _sharedLegacyValidation(ErrorCollector errorCollector) {
-    if (node is! ClassOrMixinDeclaration) {
+    if (node is! ClassDeclaration && node is! MixinDeclaration) {
       errorCollector.addError(
           'Legacy boilerplate must use classes or mixins, and not shorthand class declaration',
           errorCollector.spanFor(node));
diff --git a/lib/src/builder/parsing/members/props_and_state_mixins.dart b/lib/src/builder/parsing/members/props_and_state_mixins.dart
index 40f52cf94..548201a80 100644
--- a/lib/src/builder/parsing/members/props_and_state_mixins.dart
+++ b/lib/src/builder/parsing/members/props_and_state_mixins.dart
@@ -19,19 +19,19 @@ part of '../members.dart';
 /// See [BoilerplateMember] for more information.
 abstract class BoilerplatePropsOrStateMixin extends BoilerplateTypedMapMember
     with PropsStateStringHelpers {
-  BoilerplatePropsOrStateMixin(this.node, this.companion, VersionConfidences confidence)
+  BoilerplatePropsOrStateMixin(this.nodeHelper, this.companion, VersionConfidences confidence)
       : super(confidence) {
     meta = getPropsOrStateAnnotation(isProps, node);
   }
 
-  /// The [MixinDeclaration] backing the member
+  /// The node backing the member.
   @override
-  final ClassOrMixinDeclaration node;
+  NamedCompilationUnitMember get node => nodeHelper.node;
 
   /// A metadata class that lifts helpful fields out of [node] to a top level,
   /// in addition to providing additional getters relevant member parsing.
   @override
-  ClassishDeclaration get nodeHelper => node.asClassish();
+  final ClassishDeclaration nodeHelper;
 
   /// The companion class for the props or state mixins.
   ///
@@ -46,7 +46,7 @@ abstract class BoilerplatePropsOrStateMixin extends BoilerplateTypedMapMember
   annotations.TypedMap meta;
 
   @override
-  SimpleIdentifier get name => node.name;
+  Token get name => nodeHelper.name;
 
   @override
   String get debugString => '${super.debugString}, companion: ${companion?.name}';
@@ -67,7 +67,7 @@ abstract class BoilerplatePropsOrStateMixin extends BoilerplateTypedMapMember
             errorCollector.spanFor(node.name));
       }
 
-      if (!node.hasAbstractGetter('Map', propsOrStateString)) {
+      if (!nodeHelper.hasAbstractGetter('Map', propsOrStateString)) {
         errorCollector.addError(
             '$propsOrStateMixinString classes must declare an abstract $propsOrStateString getter `Map get $propsOrStateString;` '
             'so that they can be statically analyzed properly.',
@@ -98,7 +98,7 @@ abstract class BoilerplatePropsOrStateMixin extends BoilerplateTypedMapMember
         break;
       case Version.v3_legacyDart2Only:
         _sharedLegacyValidation();
-        checkForMetaPresence(node, errorCollector);
+        checkForMetaPresence(node.asClassish(), errorCollector);
         break;
     }
   }
@@ -109,7 +109,7 @@ abstract class BoilerplatePropsOrStateMixin extends BoilerplateTypedMapMember
 /// See [BoilerplateMember] for more information.
 class BoilerplatePropsMixin extends BoilerplatePropsOrStateMixin {
   BoilerplatePropsMixin(
-      ClassOrMixinDeclaration node, ClassishDeclaration companion, VersionConfidences confidence)
+      ClassishDeclaration node, ClassishDeclaration companion, VersionConfidences confidence)
       : super(node, companion, confidence);
 
   @override
@@ -121,7 +121,7 @@ class BoilerplatePropsMixin extends BoilerplatePropsOrStateMixin {
 /// See [BoilerplateMember] for more information.
 class BoilerplateStateMixin extends BoilerplatePropsOrStateMixin {
   BoilerplateStateMixin(
-      ClassOrMixinDeclaration node, ClassishDeclaration companion, VersionConfidences confidence)
+      ClassishDeclaration node, ClassishDeclaration companion, VersionConfidences confidence)
       : super(node, companion, confidence);
 
   @override
diff --git a/lib/src/builder/parsing/members/props_and_state_util.dart b/lib/src/builder/parsing/members/props_and_state_util.dart
index 811eeaf3b..d6ab575f4 100644
--- a/lib/src/builder/parsing/members/props_and_state_util.dart
+++ b/lib/src/builder/parsing/members/props_and_state_util.dart
@@ -68,7 +68,7 @@ annotations.TypedMap getPropsOrStateAnnotation(bool isProps, AnnotatedNode node)
 /// If a [ClassMember] exists in [node] with the name `meta`, this will
 /// throw an error if the member is not static and a warning if the member
 /// is static.
-void checkForMetaPresence(ClassOrMixinDeclaration node, ErrorCollector errorCollector) {
+void checkForMetaPresence(ClassishDeclaration node, ErrorCollector errorCollector) {
   final metaField = metaFieldOrNull(node);
   final metaMethod = metaMethodOrNull(node);
   final isNotNull = metaField != null || metaMethod != null;
diff --git a/lib/src/builder/parsing/members_from_ast.dart b/lib/src/builder/parsing/members_from_ast.dart
index e290c8cf2..8d48fb7cc 100644
--- a/lib/src/builder/parsing/members_from_ast.dart
+++ b/lib/src/builder/parsing/members_from_ast.dart
@@ -236,7 +236,7 @@ class _BoilerplateMemberDetector {
           // Special-case: `@Props()` is allowed on the new boilerplate mixins
           if (node is MixinDeclaration) {
             onPropsMixin(BoilerplatePropsMixin(
-                node,
+                classish,
                 companion,
                 _annotatedPropsOrStateMixinConfidence(classish, companion,
                     disableAnnotationAssert: true)));
@@ -253,7 +253,7 @@ class _BoilerplateMemberDetector {
           // Special-case: `@State()` is allowed on the new boilerplate mixins
           if (node is MixinDeclaration) {
             onStateMixin(BoilerplateStateMixin(
-                node,
+                classish,
                 companion,
                 _annotatedPropsOrStateMixinConfidence(classish, companion,
                     disableAnnotationAssert: true)));
@@ -264,12 +264,12 @@ class _BoilerplateMemberDetector {
           return true;
 
         case 'PropsMixin':
-          onPropsMixin(BoilerplatePropsMixin(node as ClassOrMixinDeclaration, companion,
+          onPropsMixin(BoilerplatePropsMixin(classish, companion,
               _annotatedPropsOrStateMixinConfidence(classish, companion)));
           return true;
 
         case 'StateMixin':
-          onStateMixin(BoilerplateStateMixin(node as ClassOrMixinDeclaration, companion,
+          onStateMixin(BoilerplateStateMixin(classish, companion,
               _annotatedPropsOrStateMixinConfidence(classish, companion)));
           return true;
 
@@ -409,11 +409,11 @@ class _BoilerplateMemberDetector {
 
     if (node is MixinDeclaration) {
       if (propsMixinNamePattern.hasMatch(name) && node.hasSuperclassConstraint('UiProps')) {
-        onPropsMixin(BoilerplatePropsMixin(node, companion, getConfidence()));
+        onPropsMixin(BoilerplatePropsMixin(classish, companion, getConfidence()));
         return true;
       }
       if (stateMixinNamePattern.hasMatch(name) && node.hasSuperclassConstraint('UiState')) {
-        onStateMixin(BoilerplateStateMixin(node, companion, getConfidence()));
+        onStateMixin(BoilerplateStateMixin(classish, companion, getConfidence()));
         return true;
       }
     } else {
diff --git a/lib/src/builder/util.dart b/lib/src/builder/util.dart
index a82610b0b..2072e789a 100644
--- a/lib/src/builder/util.dart
+++ b/lib/src/builder/util.dart
@@ -16,6 +16,7 @@ import 'dart:mirrors';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:build/build.dart' show AssetId;
+import 'package:over_react/src/builder/parsing.dart';
 import 'package:path/path.dart' as p;
 import 'package:source_span/source_span.dart';
 
@@ -87,7 +88,7 @@ String messageWithSpan(String message, {SourceSpan span}) {
 
 /// Returns any [FieldDeclaration]s on [node] which have the name `meta`,
 /// otherwise `null`.
-FieldDeclaration metaFieldOrNull(ClassOrMixinDeclaration node) {
+FieldDeclaration metaFieldOrNull(ClassishDeclaration node) {
   return node.members.whereType<FieldDeclaration>().firstWhere(fieldDeclarationHasMeta,
       orElse: () => null);
 }
@@ -107,7 +108,7 @@ bool fieldDeclarationHasName(FieldDeclaration field, String name) {
 
 /// Returns any [MethodDeclaration]s on [node] which have the name `meta`,
 /// otherwise `null`.
-MethodDeclaration metaMethodOrNull(ClassOrMixinDeclaration node) {
+MethodDeclaration metaMethodOrNull(ClassishDeclaration node) {
   return node.members.whereType<MethodDeclaration>().firstWhere((member) =>
       member.name.name == 'meta',
       orElse: () => null);
diff --git a/lib/src/component/abstract_transition_props.over_react.g.dart b/lib/src/component/abstract_transition_props.over_react.g.dart
index 7fbd86dfd..276543c64 100644
--- a/lib/src/component/abstract_transition_props.over_react.g.dart
+++ b/lib/src/component/abstract_transition_props.over_react.g.dart
@@ -125,8 +125,8 @@ _$$TransitionPropsMixin _$TransitionPropsMapView([Map backingProps]) =>
 abstract class _$$TransitionPropsMixin extends UiProps
     with
         TransitionPropsMixin,
-        $TransitionPropsMixin // If this generated mixin is undefined, it's likely because TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionPropsMixin, and check that $TransitionPropsMixin is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionPropsMixin, and check that $TransitionPropsMixin is exported/imported properly.
+        $TransitionPropsMixin {
   _$$TransitionPropsMixin._();
 
   factory _$$TransitionPropsMixin(Map backingMap) {
diff --git a/lib/src/component/error_boundary.over_react.g.dart b/lib/src/component/error_boundary.over_react.g.dart
index 49d935dac..3999f2a18 100644
--- a/lib/src/component/error_boundary.over_react.g.dart
+++ b/lib/src/component/error_boundary.over_react.g.dart
@@ -34,8 +34,8 @@ _$$ErrorBoundaryProps _$ErrorBoundary([Map backingProps]) =>
 abstract class _$$ErrorBoundaryProps extends UiProps
     with
         ErrorBoundaryProps,
-        $ErrorBoundaryProps // If this generated mixin is undefined, it's likely because ErrorBoundaryProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ErrorBoundaryProps, and check that $ErrorBoundaryProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ErrorBoundaryProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ErrorBoundaryProps, and check that $ErrorBoundaryProps is exported/imported properly.
+        $ErrorBoundaryProps {
   _$$ErrorBoundaryProps._();
 
   factory _$$ErrorBoundaryProps(Map backingMap) {
@@ -111,8 +111,8 @@ class _$$ErrorBoundaryProps$JsMap extends _$$ErrorBoundaryProps {
 abstract class _$$ErrorBoundaryState extends UiState
     with
         ErrorBoundaryState,
-        $ErrorBoundaryState // If this generated mixin is undefined, it's likely because ErrorBoundaryState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of ErrorBoundaryState, and check that $ErrorBoundaryState is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ErrorBoundaryState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of ErrorBoundaryState, and check that $ErrorBoundaryState is exported/imported properly.
+        $ErrorBoundaryState {
   _$$ErrorBoundaryState._();
 
   factory _$$ErrorBoundaryState(Map backingMap) {
diff --git a/lib/src/component/error_boundary_recoverable.over_react.g.dart b/lib/src/component/error_boundary_recoverable.over_react.g.dart
index e5726e3a9..604b53dbd 100644
--- a/lib/src/component/error_boundary_recoverable.over_react.g.dart
+++ b/lib/src/component/error_boundary_recoverable.over_react.g.dart
@@ -35,7 +35,8 @@ _$$RecoverableErrorBoundaryProps _$RecoverableErrorBoundary(
 abstract class _$$RecoverableErrorBoundaryProps extends UiProps
     with
         v2.ErrorBoundaryProps,
-        v2.$ErrorBoundaryProps // If this generated mixin is undefined, it's likely because v2.ErrorBoundaryProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of v2.ErrorBoundaryProps, and check that v2.$ErrorBoundaryProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because v2.ErrorBoundaryProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of v2.ErrorBoundaryProps, and check that v2.$ErrorBoundaryProps is exported/imported properly.
+        v2.$ErrorBoundaryProps
     implements
         RecoverableErrorBoundaryProps {
   _$$RecoverableErrorBoundaryProps._();
@@ -115,7 +116,8 @@ class _$$RecoverableErrorBoundaryProps$JsMap
 abstract class _$$RecoverableErrorBoundaryState extends UiState
     with
         v2.ErrorBoundaryState,
-        v2.$ErrorBoundaryState // If this generated mixin is undefined, it's likely because v2.ErrorBoundaryState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of v2.ErrorBoundaryState, and check that v2.$ErrorBoundaryState is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because v2.ErrorBoundaryState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of v2.ErrorBoundaryState, and check that v2.$ErrorBoundaryState is exported/imported properly.
+        v2.$ErrorBoundaryState
     implements
         RecoverableErrorBoundaryState {
   _$$RecoverableErrorBoundaryState._();
diff --git a/lib/src/component/resize_sensor.over_react.g.dart b/lib/src/component/resize_sensor.over_react.g.dart
index 8b4877f71..0eed4363f 100644
--- a/lib/src/component/resize_sensor.over_react.g.dart
+++ b/lib/src/component/resize_sensor.over_react.g.dart
@@ -32,8 +32,8 @@ _$$ResizeSensorProps _$ResizeSensor([Map backingProps]) => backingProps == null
 abstract class _$$ResizeSensorProps extends UiProps
     with
         ResizeSensorProps,
-        $ResizeSensorProps // If this generated mixin is undefined, it's likely because ResizeSensorProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ResizeSensorProps, and check that $ResizeSensorProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ResizeSensorProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ResizeSensorProps, and check that $ResizeSensorProps is exported/imported properly.
+        $ResizeSensorProps {
   _$$ResizeSensorProps._();
 
   factory _$$ResizeSensorProps(Map backingMap) {
diff --git a/lib/src/component/suspense_component.over_react.g.dart b/lib/src/component/suspense_component.over_react.g.dart
index c05caa2d0..14c3a71b3 100644
--- a/lib/src/component/suspense_component.over_react.g.dart
+++ b/lib/src/component/suspense_component.over_react.g.dart
@@ -57,7 +57,8 @@ final UiFactoryConfig<_$$SuspenseProps> $SuspenseConfig = _$SuspenseConfig;
 abstract class _$$SuspenseProps extends UiProps
     with
         SuspensePropsMixin,
-        $SuspensePropsMixin // If this generated mixin is undefined, it's likely because SuspensePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SuspensePropsMixin, and check that $SuspensePropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SuspensePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SuspensePropsMixin, and check that $SuspensePropsMixin is exported/imported properly.
+        $SuspensePropsMixin
     implements
         SuspenseProps {
   _$$SuspenseProps._();
diff --git a/lib/src/component/with_transition.over_react.g.dart b/lib/src/component/with_transition.over_react.g.dart
index 8d1e58a46..f87efd3e8 100644
--- a/lib/src/component/with_transition.over_react.g.dart
+++ b/lib/src/component/with_transition.over_react.g.dart
@@ -33,9 +33,11 @@ _$$WithTransitionProps _$WithTransition([Map backingProps]) =>
 abstract class _$$WithTransitionProps extends UiProps
     with
         v2.TransitionPropsMixin,
-        v2.$TransitionPropsMixin, // If this generated mixin is undefined, it's likely because v2.TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of v2.TransitionPropsMixin, and check that v2.$TransitionPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because v2.TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of v2.TransitionPropsMixin, and check that v2.$TransitionPropsMixin is exported/imported properly.
+        v2.$TransitionPropsMixin,
         WithTransitionPropsMixin,
-        $WithTransitionPropsMixin // If this generated mixin is undefined, it's likely because WithTransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of WithTransitionPropsMixin, and check that $WithTransitionPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because WithTransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of WithTransitionPropsMixin, and check that $WithTransitionPropsMixin is exported/imported properly.
+        $WithTransitionPropsMixin
     implements
         WithTransitionProps {
   _$$WithTransitionProps._();
@@ -115,8 +117,8 @@ class _$$WithTransitionProps$JsMap extends _$$WithTransitionProps {
 abstract class _$$WithTransitionState extends UiState
     with
         WithTransitionState,
-        $WithTransitionState // If this generated mixin is undefined, it's likely because WithTransitionState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of WithTransitionState, and check that $WithTransitionState is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because WithTransitionState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of WithTransitionState, and check that $WithTransitionState is exported/imported properly.
+        $WithTransitionState {
   _$$WithTransitionState._();
 
   factory _$$WithTransitionState(Map backingMap) {
diff --git a/lib/src/util/safe_render_manager/safe_render_manager_helper.over_react.g.dart b/lib/src/util/safe_render_manager/safe_render_manager_helper.over_react.g.dart
index 7c750a143..68797aa13 100644
--- a/lib/src/util/safe_render_manager/safe_render_manager_helper.over_react.g.dart
+++ b/lib/src/util/safe_render_manager/safe_render_manager_helper.over_react.g.dart
@@ -33,8 +33,8 @@ _$$SafeRenderManagerHelperProps _$SafeRenderManagerHelper([Map backingProps]) =>
 abstract class _$$SafeRenderManagerHelperProps extends UiProps
     with
         SafeRenderManagerHelperProps,
-        $SafeRenderManagerHelperProps // If this generated mixin is undefined, it's likely because SafeRenderManagerHelperProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SafeRenderManagerHelperProps, and check that $SafeRenderManagerHelperProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because SafeRenderManagerHelperProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SafeRenderManagerHelperProps, and check that $SafeRenderManagerHelperProps is exported/imported properly.
+        $SafeRenderManagerHelperProps {
   _$$SafeRenderManagerHelperProps._();
 
   factory _$$SafeRenderManagerHelperProps(Map backingMap) {
@@ -112,8 +112,8 @@ class _$$SafeRenderManagerHelperProps$JsMap
 abstract class _$$SafeRenderManagerHelperState extends UiState
     with
         SafeRenderManagerHelperState,
-        $SafeRenderManagerHelperState // If this generated mixin is undefined, it's likely because SafeRenderManagerHelperState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of SafeRenderManagerHelperState, and check that $SafeRenderManagerHelperState is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because SafeRenderManagerHelperState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of SafeRenderManagerHelperState, and check that $SafeRenderManagerHelperState is exported/imported properly.
+        $SafeRenderManagerHelperState {
   _$$SafeRenderManagerHelperState._();
 
   factory _$$SafeRenderManagerHelperState(Map backingMap) {
diff --git a/pubspec.yaml b/pubspec.yaml
index b73bbf060..1df00e0cb 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -7,11 +7,11 @@ environment:
 
 dependencies:
   collection: ^1.14.11
-  analyzer: '>=1.7.2 <3.0.0'
+  analyzer: ^5.1.0
   build: '>=1.0.0 <3.0.0'
-  built_redux: ^8.0.0
+  built_redux: ^8.0.6
   built_value: ^8.0.0
-  dart_style: '>=1.2.5 <3.0.0'
+  dart_style: ^2.0.0
   js: ^0.6.1+1
   logging: ^1.0.0
   meta: ^1.6.0
@@ -20,7 +20,7 @@ dependencies:
   redux: '>=3.0.0 <6.0.0'
   source_span: ^1.4.1
   transformer_utils: ^0.2.6
-  w_common: '>=2.0.0 <4.0.0'
+  w_common: ^3.0.0
   w_flux: ^2.10.21
   platform_detect: '>=1.3.4 <3.0.0'
   quiver: ">=0.25.0 <4.0.0"
@@ -28,17 +28,15 @@ dependencies:
 
 dev_dependencies:
   build_resolvers: '>=1.0.5 <3.0.0'
-  build_runner: '>=1.7.1 <3.0.0'
-  build_test: ">=0.10.9 <3.0.0"
-  build_web_compilers: '>=2.12.0 <4.0.0'
+  build_runner: ^2.0.0
+  build_test: ^2.0.0
+  build_web_compilers: ^3.0.0
   built_value_generator: ^8.0.0
-  dart_dev: '>=3.6.4 <5.0.0'
-  dependency_validator: '>=2.0.0 <4.0.0'
+  dart_dev: ^4.0.0
+  dependency_validator: ^3.0.0
   glob: ^2.0.0
   io: '>=0.3.2+1 <2.0.0'
-  # Pin mockito to work around https://github.com/dart-lang/mockito/issues/552
-  # until we can get to 5.3.1, which requires a newer analyzer.
-  mockito: '>=5.0.0 <5.3.0'
+  mockito: ^5.3.1
   react_testing_library: ^2.1.0
   over_react_test: ^2.10.2
   pedantic: ^1.8.0
diff --git a/test/mockito.mocks.dart b/test/mockito.mocks.dart
index 106539dc6..7a1f0ab6f 100644
--- a/test/mockito.mocks.dart
+++ b/test/mockito.mocks.dart
@@ -1,4 +1,4 @@
-// Mocks generated by Mockito 5.2.0 from annotations
+// Mocks generated by Mockito 5.4.0 from annotations
 // in over_react/test/mockito.dart.
 // Do not manually edit this file.
 
@@ -17,6 +17,7 @@ import 'package:mockito/mockito.dart' as _i1;
 // ignore_for_file: prefer_const_constructors
 // ignore_for_file: unnecessary_parenthesis
 // ignore_for_file: camel_case_types
+// ignore_for_file: subtype_of_sealed_class
 
 /// A class which mocks [Logger].
 ///
diff --git a/test/over_react/component/abstract_transition_test.over_react.g.dart b/test/over_react/component/abstract_transition_test.over_react.g.dart
index 9bb14dbd8..108b44f2b 100644
--- a/test/over_react/component/abstract_transition_test.over_react.g.dart
+++ b/test/over_react/component/abstract_transition_test.over_react.g.dart
@@ -32,9 +32,11 @@ _$$TransitionerProps _$Transitioner([Map backingProps]) => backingProps == null
 abstract class _$$TransitionerProps extends UiProps
     with
         TransitionerPropsMixin,
-        $TransitionerPropsMixin, // If this generated mixin is undefined, it's likely because TransitionerPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionerPropsMixin, and check that $TransitionerPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TransitionerPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionerPropsMixin, and check that $TransitionerPropsMixin is exported/imported properly.
+        $TransitionerPropsMixin,
         TransitionPropsMixin,
-        $TransitionPropsMixin // If this generated mixin is undefined, it's likely because TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionPropsMixin, and check that $TransitionPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionPropsMixin, and check that $TransitionPropsMixin is exported/imported properly.
+        $TransitionPropsMixin
     implements
         TransitionerProps {
   _$$TransitionerProps._();
@@ -114,7 +116,8 @@ class _$$TransitionerProps$JsMap extends _$$TransitionerProps {
 abstract class _$$TransitionerState extends UiState
     with
         AbstractTransitionState,
-        $AbstractTransitionState // If this generated mixin is undefined, it's likely because AbstractTransitionState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of AbstractTransitionState, and check that $AbstractTransitionState is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because AbstractTransitionState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of AbstractTransitionState, and check that $AbstractTransitionState is exported/imported properly.
+        $AbstractTransitionState
     implements
         TransitionerState {
   _$$TransitionerState._();
diff --git a/test/over_react/component/element_type_test.over_react.g.dart b/test/over_react/component/element_type_test.over_react.g.dart
index 8e28703a5..3f99016f0 100644
--- a/test/over_react/component/element_type_test.over_react.g.dart
+++ b/test/over_react/component/element_type_test.over_react.g.dart
@@ -32,8 +32,8 @@ _$$CustomTestProps _$CustomTest([Map backingProps]) => backingProps == null
 abstract class _$$CustomTestProps extends UiProps
     with
         CustomTestProps,
-        $CustomTestProps // If this generated mixin is undefined, it's likely because CustomTestProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomTestProps, and check that $CustomTestProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because CustomTestProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomTestProps, and check that $CustomTestProps is exported/imported properly.
+        $CustomTestProps {
   _$$CustomTestProps._();
 
   factory _$$CustomTestProps(Map backingMap) {
@@ -214,8 +214,8 @@ final UiFactoryConfig<_$$CustomFnTestProps> $CustomFnTestConfig =
 abstract class _$$CustomFnTestProps extends UiProps
     with
         CustomFnTestProps,
-        $CustomFnTestProps // If this generated mixin is undefined, it's likely because CustomFnTestProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomFnTestProps, and check that $CustomFnTestProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because CustomFnTestProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomFnTestProps, and check that $CustomFnTestProps is exported/imported properly.
+        $CustomFnTestProps {
   _$$CustomFnTestProps._();
 
   factory _$$CustomFnTestProps(Map backingMap) {
diff --git a/test/over_react/component/error_boundary/shared_stack_tests.over_react.g.dart b/test/over_react/component/error_boundary/shared_stack_tests.over_react.g.dart
index 0230a62f4..099f68604 100644
--- a/test/over_react/component/error_boundary/shared_stack_tests.over_react.g.dart
+++ b/test/over_react/component/error_boundary/shared_stack_tests.over_react.g.dart
@@ -33,8 +33,8 @@ _$$ThrowingComponent2Props _$ThrowingComponent2([Map backingProps]) =>
 abstract class _$$ThrowingComponent2Props extends UiProps
     with
         ThrowingComponent2Props,
-        $ThrowingComponent2Props // If this generated mixin is undefined, it's likely because ThrowingComponent2Props is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ThrowingComponent2Props, and check that $ThrowingComponent2Props is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ThrowingComponent2Props is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ThrowingComponent2Props, and check that $ThrowingComponent2Props is exported/imported properly.
+        $ThrowingComponent2Props {
   _$$ThrowingComponent2Props._();
 
   factory _$$ThrowingComponent2Props(Map backingMap) {
@@ -326,8 +326,8 @@ final UiFactoryConfig<_$$ThrowingFunctionComponentProps>
 abstract class _$$ThrowingFunctionComponentProps extends UiProps
     with
         ThrowingFunctionComponentProps,
-        $ThrowingFunctionComponentProps // If this generated mixin is undefined, it's likely because ThrowingFunctionComponentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ThrowingFunctionComponentProps, and check that $ThrowingFunctionComponentProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ThrowingFunctionComponentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ThrowingFunctionComponentProps, and check that $ThrowingFunctionComponentProps is exported/imported properly.
+        $ThrowingFunctionComponentProps {
   _$$ThrowingFunctionComponentProps._();
 
   factory _$$ThrowingFunctionComponentProps(Map backingMap) {
@@ -415,8 +415,8 @@ final UiFactoryConfig<_$$ThrowingForwardRefComponentProps>
 abstract class _$$ThrowingForwardRefComponentProps extends UiProps
     with
         ThrowingForwardRefComponentProps,
-        $ThrowingForwardRefComponentProps // If this generated mixin is undefined, it's likely because ThrowingForwardRefComponentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ThrowingForwardRefComponentProps, and check that $ThrowingForwardRefComponentProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ThrowingForwardRefComponentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ThrowingForwardRefComponentProps, and check that $ThrowingForwardRefComponentProps is exported/imported properly.
+        $ThrowingForwardRefComponentProps {
   _$$ThrowingForwardRefComponentProps._();
 
   factory _$$ThrowingForwardRefComponentProps(Map backingMap) {
diff --git a/test/over_react/component/fixtures/lazy_load_me_component.over_react.g.dart b/test/over_react/component/fixtures/lazy_load_me_component.over_react.g.dart
index d9c8d7e6a..35ea035d4 100644
--- a/test/over_react/component/fixtures/lazy_load_me_component.over_react.g.dart
+++ b/test/over_react/component/fixtures/lazy_load_me_component.over_react.g.dart
@@ -28,7 +28,8 @@ final UiFactoryConfig<_$$LazyLoadMeProps> $LazyLoadMeConfig =
 abstract class _$$LazyLoadMeProps extends UiProps
     with
         LazyLoadMePropsMixin,
-        $LazyLoadMePropsMixin // If this generated mixin is undefined, it's likely because LazyLoadMePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of LazyLoadMePropsMixin, and check that $LazyLoadMePropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because LazyLoadMePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of LazyLoadMePropsMixin, and check that $LazyLoadMePropsMixin is exported/imported properly.
+        $LazyLoadMePropsMixin
     implements
         LazyLoadMeProps {
   _$$LazyLoadMeProps._();
diff --git a/test/over_react/component/fixtures/lazy_load_me_props.over_react.g.dart b/test/over_react/component/fixtures/lazy_load_me_props.over_react.g.dart
index 67b4a467e..cf9a2f178 100644
--- a/test/over_react/component/fixtures/lazy_load_me_props.over_react.g.dart
+++ b/test/over_react/component/fixtures/lazy_load_me_props.over_react.g.dart
@@ -53,8 +53,8 @@ _$$LazyLoadMePropsMixin _$LazyLoadMePropsMapView([Map backingProps]) =>
 abstract class _$$LazyLoadMePropsMixin extends UiProps
     with
         LazyLoadMePropsMixin,
-        $LazyLoadMePropsMixin // If this generated mixin is undefined, it's likely because LazyLoadMePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of LazyLoadMePropsMixin, and check that $LazyLoadMePropsMixin is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because LazyLoadMePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of LazyLoadMePropsMixin, and check that $LazyLoadMePropsMixin is exported/imported properly.
+        $LazyLoadMePropsMixin {
   _$$LazyLoadMePropsMixin._();
 
   factory _$$LazyLoadMePropsMixin(Map backingMap) {
diff --git a/test/over_react/component/fixtures/pure_test_components.over_react.g.dart b/test/over_react/component/fixtures/pure_test_components.over_react.g.dart
index e3bf68c3a..c2969c949 100644
--- a/test/over_react/component/fixtures/pure_test_components.over_react.g.dart
+++ b/test/over_react/component/fixtures/pure_test_components.over_react.g.dart
@@ -33,7 +33,8 @@ _$$PureTestWrapperProps _$PureTestWrapper([Map backingProps]) =>
 abstract class _$$PureTestWrapperProps extends UiProps
     with
         SharedPureTestPropsMixin,
-        $SharedPureTestPropsMixin // If this generated mixin is undefined, it's likely because SharedPureTestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SharedPureTestPropsMixin, and check that $SharedPureTestPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SharedPureTestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SharedPureTestPropsMixin, and check that $SharedPureTestPropsMixin is exported/imported properly.
+        $SharedPureTestPropsMixin
     implements
         PureTestWrapperProps {
   _$$PureTestWrapperProps._();
@@ -181,9 +182,11 @@ _$$PureTestProps _$PureTest([Map backingProps]) => backingProps == null
 abstract class _$$PureTestProps extends UiProps
     with
         SharedPureTestPropsMixin,
-        $SharedPureTestPropsMixin, // If this generated mixin is undefined, it's likely because SharedPureTestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SharedPureTestPropsMixin, and check that $SharedPureTestPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SharedPureTestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SharedPureTestPropsMixin, and check that $SharedPureTestPropsMixin is exported/imported properly.
+        $SharedPureTestPropsMixin,
         PureTestPropsMixin,
-        $PureTestPropsMixin // If this generated mixin is undefined, it's likely because PureTestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of PureTestPropsMixin, and check that $PureTestPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because PureTestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of PureTestPropsMixin, and check that $PureTestPropsMixin is exported/imported properly.
+        $PureTestPropsMixin
     implements
         PureTestProps {
   _$$PureTestProps._();
@@ -263,8 +266,8 @@ class _$$PureTestProps$JsMap extends _$$PureTestProps {
 abstract class _$$PureTestState extends UiState
     with
         PureTestState,
-        $PureTestState // If this generated mixin is undefined, it's likely because PureTestState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of PureTestState, and check that $PureTestState is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because PureTestState is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of PureTestState, and check that $PureTestState is exported/imported properly.
+        $PureTestState {
   _$$PureTestState._();
 
   factory _$$PureTestState(Map backingMap) {
diff --git a/test/over_react/component/memo_test.over_react.g.dart b/test/over_react/component/memo_test.over_react.g.dart
index 971b6bfe2..302008ea9 100644
--- a/test/over_react/component/memo_test.over_react.g.dart
+++ b/test/over_react/component/memo_test.over_react.g.dart
@@ -239,8 +239,8 @@ final UiFactoryConfig<_$$FunctionCustomPropsProps> $FunctionCustomPropsConfig =
 abstract class _$$FunctionCustomPropsProps extends UiProps
     with
         FunctionCustomPropsProps,
-        $FunctionCustomPropsProps // If this generated mixin is undefined, it's likely because FunctionCustomPropsProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of FunctionCustomPropsProps, and check that $FunctionCustomPropsProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because FunctionCustomPropsProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of FunctionCustomPropsProps, and check that $FunctionCustomPropsProps is exported/imported properly.
+        $FunctionCustomPropsProps {
   _$$FunctionCustomPropsProps._();
 
   factory _$$FunctionCustomPropsProps(Map backingMap) {
diff --git a/test/over_react/component/ref_util_test.over_react.g.dart b/test/over_react/component/ref_util_test.over_react.g.dart
index 6d19238ff..9acdf545c 100644
--- a/test/over_react/component/ref_util_test.over_react.g.dart
+++ b/test/over_react/component/ref_util_test.over_react.g.dart
@@ -32,8 +32,8 @@ _$$BasicProps _$Basic([Map backingProps]) => backingProps == null
 abstract class _$$BasicProps extends UiProps
     with
         BasicProps,
-        $BasicProps // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
+        $BasicProps {
   _$$BasicProps._();
 
   factory _$$BasicProps(Map backingMap) {
@@ -220,8 +220,8 @@ final UiFactoryConfig<_$$BasicUiFunctionProps> $BasicUiFunctionConfig =
 abstract class _$$BasicUiFunctionProps extends UiProps
     with
         BasicUiFunctionProps,
-        $BasicUiFunctionProps // If this generated mixin is undefined, it's likely because BasicUiFunctionProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicUiFunctionProps, and check that $BasicUiFunctionProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because BasicUiFunctionProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicUiFunctionProps, and check that $BasicUiFunctionProps is exported/imported properly.
+        $BasicUiFunctionProps {
   _$$BasicUiFunctionProps._();
 
   factory _$$BasicUiFunctionProps(Map backingMap) {
@@ -307,7 +307,8 @@ final UiFactoryConfig<_$$SecondaryBasicUiFunctionProps>
 abstract class _$$SecondaryBasicUiFunctionProps extends UiProps
     with
         BasicUiFunctionProps,
-        $BasicUiFunctionProps // If this generated mixin is undefined, it's likely because BasicUiFunctionProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicUiFunctionProps, and check that $BasicUiFunctionProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because BasicUiFunctionProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicUiFunctionProps, and check that $BasicUiFunctionProps is exported/imported properly.
+        $BasicUiFunctionProps
     implements
         SecondaryBasicUiFunctionProps {
   _$$SecondaryBasicUiFunctionProps._();
diff --git a/test/over_react/component/with_transition_test.over_react.g.dart b/test/over_react/component/with_transition_test.over_react.g.dart
index e7e3b5fdf..35a108b01 100644
--- a/test/over_react/component/with_transition_test.over_react.g.dart
+++ b/test/over_react/component/with_transition_test.over_react.g.dart
@@ -33,9 +33,11 @@ _$$WithTransitionTesterProps _$WithTransitionTester([Map backingProps]) =>
 abstract class _$$WithTransitionTesterProps extends UiProps
     with
         WithTransitionPropsMixin,
-        $WithTransitionPropsMixin, // If this generated mixin is undefined, it's likely because WithTransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of WithTransitionPropsMixin, and check that $WithTransitionPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because WithTransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of WithTransitionPropsMixin, and check that $WithTransitionPropsMixin is exported/imported properly.
+        $WithTransitionPropsMixin,
         TransitionPropsMixin,
-        $TransitionPropsMixin // If this generated mixin is undefined, it's likely because TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionPropsMixin, and check that $TransitionPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TransitionPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TransitionPropsMixin, and check that $TransitionPropsMixin is exported/imported properly.
+        $TransitionPropsMixin
     implements
         WithTransitionTesterProps {
   _$$WithTransitionTesterProps._();
diff --git a/test/over_react/component_declaration/function_type_checking_test/components.over_react.g.dart b/test/over_react/component_declaration/function_type_checking_test/components.over_react.g.dart
index b3384078c..7d61bbbed 100644
--- a/test/over_react/component_declaration/function_type_checking_test/components.over_react.g.dart
+++ b/test/over_react/component_declaration/function_type_checking_test/components.over_react.g.dart
@@ -39,8 +39,8 @@ abstract class _$$DoNotReferenceThisFactoryExceptForInASingleTestProps
     extends UiProps
     with
         DoNotReferenceThisFactoryExceptForInASingleTestProps,
-        $DoNotReferenceThisFactoryExceptForInASingleTestProps // If this generated mixin is undefined, it's likely because DoNotReferenceThisFactoryExceptForInASingleTestProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoNotReferenceThisFactoryExceptForInASingleTestProps, and check that $DoNotReferenceThisFactoryExceptForInASingleTestProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because DoNotReferenceThisFactoryExceptForInASingleTestProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoNotReferenceThisFactoryExceptForInASingleTestProps, and check that $DoNotReferenceThisFactoryExceptForInASingleTestProps is exported/imported properly.
+        $DoNotReferenceThisFactoryExceptForInASingleTestProps {
   _$$DoNotReferenceThisFactoryExceptForInASingleTestProps._();
 
   factory _$$DoNotReferenceThisFactoryExceptForInASingleTestProps(
@@ -390,8 +390,8 @@ final UiFactoryConfig<_$$TestAProps> $TestAConfig = _$TestAConfig;
 abstract class _$$TestAProps extends UiProps
     with
         TestAProps,
-        $TestAProps // If this generated mixin is undefined, it's likely because TestAProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestAProps, and check that $TestAProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestAProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestAProps, and check that $TestAProps is exported/imported properly.
+        $TestAProps {
   _$$TestAProps._();
 
   factory _$$TestAProps(Map backingMap) {
@@ -474,8 +474,8 @@ final UiFactoryConfig<_$$TestBProps> $TestBConfig = _$TestBConfig;
 abstract class _$$TestBProps extends UiProps
     with
         TestBProps,
-        $TestBProps // If this generated mixin is undefined, it's likely because TestBProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestBProps, and check that $TestBProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestBProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestBProps, and check that $TestBProps is exported/imported properly.
+        $TestBProps {
   _$$TestBProps._();
 
   factory _$$TestBProps(Map backingMap) {
@@ -559,8 +559,8 @@ final UiFactoryConfig<_$$TestParentProps> $TestParentConfig =
 abstract class _$$TestParentProps extends UiProps
     with
         TestParentProps,
-        $TestParentProps // If this generated mixin is undefined, it's likely because TestParentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestParentProps, and check that $TestParentProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestParentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestParentProps, and check that $TestParentProps is exported/imported properly.
+        $TestParentProps {
   _$$TestParentProps._();
 
   factory _$$TestParentProps(Map backingMap) {
@@ -645,8 +645,8 @@ final UiFactoryConfig<_$$TestSubtypeProps> $TestSubtypeConfig =
 abstract class _$$TestSubtypeProps extends UiProps
     with
         TestSubtypeProps,
-        $TestSubtypeProps // If this generated mixin is undefined, it's likely because TestSubtypeProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSubtypeProps, and check that $TestSubtypeProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestSubtypeProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSubtypeProps, and check that $TestSubtypeProps is exported/imported properly.
+        $TestSubtypeProps {
   _$$TestSubtypeProps._();
 
   factory _$$TestSubtypeProps(Map backingMap) {
@@ -731,8 +731,8 @@ final UiFactoryConfig<_$$TestSubsubtypeProps> $TestSubsubtypeConfig =
 abstract class _$$TestSubsubtypeProps extends UiProps
     with
         TestSubsubtypeProps,
-        $TestSubsubtypeProps // If this generated mixin is undefined, it's likely because TestSubsubtypeProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSubsubtypeProps, and check that $TestSubsubtypeProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestSubsubtypeProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSubsubtypeProps, and check that $TestSubsubtypeProps is exported/imported properly.
+        $TestSubsubtypeProps {
   _$$TestSubsubtypeProps._();
 
   factory _$$TestSubsubtypeProps(Map backingMap) {
@@ -817,8 +817,8 @@ final UiFactoryConfig<_$$TestExtendtypeProps> $TestExtendtypeConfig =
 abstract class _$$TestExtendtypeProps extends UiProps
     with
         TestExtendtypeProps,
-        $TestExtendtypeProps // If this generated mixin is undefined, it's likely because TestExtendtypeProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestExtendtypeProps, and check that $TestExtendtypeProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestExtendtypeProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestExtendtypeProps, and check that $TestExtendtypeProps is exported/imported properly.
+        $TestExtendtypeProps {
   _$$TestExtendtypeProps._();
 
   factory _$$TestExtendtypeProps(Map backingMap) {
@@ -903,8 +903,8 @@ final UiFactoryConfig<_$$OneLevelWrapperProps> $OneLevelWrapperConfig =
 abstract class _$$OneLevelWrapperProps extends UiProps
     with
         OneLevelWrapperProps,
-        $OneLevelWrapperProps // If this generated mixin is undefined, it's likely because OneLevelWrapperProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of OneLevelWrapperProps, and check that $OneLevelWrapperProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because OneLevelWrapperProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of OneLevelWrapperProps, and check that $OneLevelWrapperProps is exported/imported properly.
+        $OneLevelWrapperProps {
   _$$OneLevelWrapperProps._();
 
   factory _$$OneLevelWrapperProps(Map backingMap) {
@@ -989,8 +989,8 @@ final UiFactoryConfig<_$$TwoLevelWrapperProps> $TwoLevelWrapperConfig =
 abstract class _$$TwoLevelWrapperProps extends UiProps
     with
         TwoLevelWrapperProps,
-        $TwoLevelWrapperProps // If this generated mixin is undefined, it's likely because TwoLevelWrapperProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TwoLevelWrapperProps, and check that $TwoLevelWrapperProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TwoLevelWrapperProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TwoLevelWrapperProps, and check that $TwoLevelWrapperProps is exported/imported properly.
+        $TwoLevelWrapperProps {
   _$$TwoLevelWrapperProps._();
 
   factory _$$TwoLevelWrapperProps(Map backingMap) {
@@ -1076,8 +1076,8 @@ final UiFactoryConfig<_$$TestUninitializedParentProps>
 abstract class _$$TestUninitializedParentProps extends UiProps
     with
         TestUninitializedParentProps,
-        $TestUninitializedParentProps // If this generated mixin is undefined, it's likely because TestUninitializedParentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestUninitializedParentProps, and check that $TestUninitializedParentProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestUninitializedParentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestUninitializedParentProps, and check that $TestUninitializedParentProps is exported/imported properly.
+        $TestUninitializedParentProps {
   _$$TestUninitializedParentProps._();
 
   factory _$$TestUninitializedParentProps(Map backingMap) {
diff --git a/test/over_react/component_declaration/redux_component_test/test_reducer.g.dart b/test/over_react/component_declaration/redux_component_test/test_reducer.g.dart
index 298355e77..271446242 100644
--- a/test/over_react/component_declaration/redux_component_test/test_reducer.g.dart
+++ b/test/over_react/component_declaration/redux_component_test/test_reducer.g.dart
@@ -1,6 +1,6 @@
 // GENERATED CODE - DO NOT MODIFY BY HAND
 
-part of over_react.component_declaration.redux_component.reducer;
+part of 'test_reducer.dart';
 
 // **************************************************************************
 // BuiltReduxGenerator
@@ -64,7 +64,11 @@ class _$BaseState extends BaseState {
 
   @override
   int get hashCode {
-    return $jf($jc($jc(0, count1.hashCode), count2.hashCode));
+    var _$hash = 0;
+    _$hash = $jc(_$hash, count1.hashCode);
+    _$hash = $jc(_$hash, count2.hashCode);
+    _$hash = $jf(_$hash);
+    return _$hash;
   }
 
   @override
@@ -125,4 +129,4 @@ class BaseStateBuilder implements Builder<BaseState, BaseStateBuilder> {
   }
 }
 
-// ignore_for_file: always_put_control_body_on_new_line,always_specify_types,annotate_overrides,avoid_annotating_with_dynamic,avoid_as,avoid_catches_without_on_clauses,avoid_returning_this,deprecated_member_use_from_same_package,lines_longer_than_80_chars,no_leading_underscores_for_local_identifiers,omit_local_variable_types,prefer_expression_function_bodies,sort_constructors_first,test_types_in_equals,unnecessary_const,unnecessary_new,unnecessary_lambdas
+// ignore_for_file: deprecated_member_use_from_same_package,type=lint
diff --git a/test/over_react/util/cast_ui_factory_test.over_react.g.dart b/test/over_react/util/cast_ui_factory_test.over_react.g.dart
index cd852c602..801115768 100644
--- a/test/over_react/util/cast_ui_factory_test.over_react.g.dart
+++ b/test/over_react/util/cast_ui_factory_test.over_react.g.dart
@@ -32,8 +32,8 @@ _$$BasicProps _$Basic([Map backingProps]) => backingProps == null
 abstract class _$$BasicProps extends UiProps
     with
         BasicProps,
-        $BasicProps // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
+        $BasicProps {
   _$$BasicProps._();
 
   factory _$$BasicProps(Map backingMap) {
diff --git a/test/over_react/util/component_debug_name_test.over_react.g.dart b/test/over_react/util/component_debug_name_test.over_react.g.dart
index 1443ed3da..074437e2c 100644
--- a/test/over_react/util/component_debug_name_test.over_react.g.dart
+++ b/test/over_react/util/component_debug_name_test.over_react.g.dart
@@ -33,8 +33,8 @@ _$$TestComponent2Props _$TestComponent2([Map backingProps]) =>
 abstract class _$$TestComponent2Props extends UiProps
     with
         TestComponent2Props,
-        $TestComponent2Props // If this generated mixin is undefined, it's likely because TestComponent2Props is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestComponent2Props, and check that $TestComponent2Props is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestComponent2Props is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestComponent2Props, and check that $TestComponent2Props is exported/imported properly.
+        $TestComponent2Props {
   _$$TestComponent2Props._();
 
   factory _$$TestComponent2Props(Map backingMap) {
diff --git a/test/over_react/util/js_component_test.over_react.g.dart b/test/over_react/util/js_component_test.over_react.g.dart
index 32cfe167f..eb49c1a00 100644
--- a/test/over_react/util/js_component_test.over_react.g.dart
+++ b/test/over_react/util/js_component_test.over_react.g.dart
@@ -165,9 +165,11 @@ final UiFactoryConfig<_$$TestProps> $_TestConfig = _$_TestConfig;
 abstract class _$$TestProps extends UiProps
     with
         TestPropsMixin,
-        $TestPropsMixin, // If this generated mixin is undefined, it's likely because TestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestPropsMixin, and check that $TestPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TestPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestPropsMixin, and check that $TestPropsMixin is exported/imported properly.
+        $TestPropsMixin,
         ASecondPropsMixin,
-        $ASecondPropsMixin // If this generated mixin is undefined, it's likely because ASecondPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ASecondPropsMixin, and check that $ASecondPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because ASecondPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ASecondPropsMixin, and check that $ASecondPropsMixin is exported/imported properly.
+        $ASecondPropsMixin
     implements
         TestProps {
   _$$TestProps._();
diff --git a/test/over_react/util/prop_conversion_test.over_react.g.dart b/test/over_react/util/prop_conversion_test.over_react.g.dart
index f4c24bf01..4e9223020 100644
--- a/test/over_react/util/prop_conversion_test.over_react.g.dart
+++ b/test/over_react/util/prop_conversion_test.over_react.g.dart
@@ -33,8 +33,8 @@ _$$ClassComponentProps _$ClassComponent([Map backingProps]) =>
 abstract class _$$ClassComponentProps extends UiProps
     with
         ClassComponentProps,
-        $ClassComponentProps // If this generated mixin is undefined, it's likely because ClassComponentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ClassComponentProps, and check that $ClassComponentProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ClassComponentProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ClassComponentProps, and check that $ClassComponentProps is exported/imported properly.
+        $ClassComponentProps {
   _$$ClassComponentProps._();
 
   factory _$$ClassComponentProps(Map backingMap) {
@@ -426,8 +426,8 @@ final UiFactoryConfig<_$$ExpectsDartMapPropProps> $ExpectsDartMapPropConfig =
 abstract class _$$ExpectsDartMapPropProps extends UiProps
     with
         ExpectsDartMapPropProps,
-        $ExpectsDartMapPropProps // If this generated mixin is undefined, it's likely because ExpectsDartMapPropProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExpectsDartMapPropProps, and check that $ExpectsDartMapPropProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ExpectsDartMapPropProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExpectsDartMapPropProps, and check that $ExpectsDartMapPropProps is exported/imported properly.
+        $ExpectsDartMapPropProps {
   _$$ExpectsDartMapPropProps._();
 
   factory _$$ExpectsDartMapPropProps(Map backingMap) {
@@ -512,8 +512,8 @@ final UiFactoryConfig<_$$ExpectsDartStylePropProps>
 abstract class _$$ExpectsDartStylePropProps extends UiProps
     with
         ExpectsDartStylePropProps,
-        $ExpectsDartStylePropProps // If this generated mixin is undefined, it's likely because ExpectsDartStylePropProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExpectsDartStylePropProps, and check that $ExpectsDartStylePropProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ExpectsDartStylePropProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExpectsDartStylePropProps, and check that $ExpectsDartStylePropProps is exported/imported properly.
+        $ExpectsDartStylePropProps {
   _$$ExpectsDartStylePropProps._();
 
   factory _$$ExpectsDartStylePropProps(Map backingMap) {
@@ -600,8 +600,8 @@ final UiFactoryConfig<_$$ExpectsListChildrenPropProps>
 abstract class _$$ExpectsListChildrenPropProps extends UiProps
     with
         ExpectsListChildrenPropProps,
-        $ExpectsListChildrenPropProps // If this generated mixin is undefined, it's likely because ExpectsListChildrenPropProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExpectsListChildrenPropProps, and check that $ExpectsListChildrenPropProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because ExpectsListChildrenPropProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExpectsListChildrenPropProps, and check that $ExpectsListChildrenPropProps is exported/imported properly.
+        $ExpectsListChildrenPropProps {
   _$$ExpectsListChildrenPropProps._();
 
   factory _$$ExpectsListChildrenPropProps(Map backingMap) {
@@ -688,8 +688,8 @@ final UiFactoryConfig<_$$BasicForwardRefProps> $BasicForwardRefConfig =
 abstract class _$$BasicForwardRefProps extends UiProps
     with
         BasicForwardRefProps,
-        $BasicForwardRefProps // If this generated mixin is undefined, it's likely because BasicForwardRefProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicForwardRefProps, and check that $BasicForwardRefProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because BasicForwardRefProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicForwardRefProps, and check that $BasicForwardRefProps is exported/imported properly.
+        $BasicForwardRefProps {
   _$$BasicForwardRefProps._();
 
   factory _$$BasicForwardRefProps(Map backingMap) {
@@ -774,9 +774,11 @@ final UiFactoryConfig<_$$DartTestJsWrapperProps> $DartTestJsWrapperConfig =
 abstract class _$$DartTestJsWrapperProps extends UiProps
     with
         TestJsProps,
-        $TestJsProps, // If this generated mixin is undefined, it's likely because TestJsProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestJsProps, and check that $TestJsProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TestJsProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestJsProps, and check that $TestJsProps is exported/imported properly.
+        $TestJsProps,
         DartTestJsWrapperPropsMixin,
-        $DartTestJsWrapperPropsMixin // If this generated mixin is undefined, it's likely because DartTestJsWrapperPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DartTestJsWrapperPropsMixin, and check that $DartTestJsWrapperPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because DartTestJsWrapperPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DartTestJsWrapperPropsMixin, and check that $DartTestJsWrapperPropsMixin is exported/imported properly.
+        $DartTestJsWrapperPropsMixin
     implements
         DartTestJsWrapperProps {
   _$$DartTestJsWrapperProps._();
@@ -863,8 +865,8 @@ final UiFactoryConfig<_$$TestJsProps> $TestJsConfig = _$TestJsConfig;
 abstract class _$$TestJsProps extends UiProps
     with
         TestJsProps,
-        $TestJsProps // If this generated mixin is undefined, it's likely because TestJsProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestJsProps, and check that $TestJsProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestJsProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestJsProps, and check that $TestJsProps is exported/imported properly.
+        $TestJsProps {
   _$$TestJsProps._();
 
   factory _$$TestJsProps(Map backingMap) {
diff --git a/test/over_react_redux/fixtures/counter_fn.over_react.g.dart b/test/over_react_redux/fixtures/counter_fn.over_react.g.dart
index 75172dcba..7bbd8f739 100644
--- a/test/over_react_redux/fixtures/counter_fn.over_react.g.dart
+++ b/test/over_react_redux/fixtures/counter_fn.over_react.g.dart
@@ -139,8 +139,8 @@ final UiFactoryConfig<_$$CounterFnProps> $CounterFnConfig = _$CounterFnConfig;
 abstract class _$$CounterFnProps extends UiProps
     with
         CounterFnProps,
-        $CounterFnProps // If this generated mixin is undefined, it's likely because CounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterFnProps, and check that $CounterFnProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because CounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterFnProps, and check that $CounterFnProps is exported/imported properly.
+        $CounterFnProps {
   _$$CounterFnProps._();
 
   factory _$$CounterFnProps(Map backingMap) {
@@ -225,9 +225,11 @@ final UiFactoryConfig<_$$ModelCounterFnProps> $ModelCounterFnConfig =
 abstract class _$$ModelCounterFnProps extends UiProps
     with
         CounterFnProps,
-        $CounterFnProps, // If this generated mixin is undefined, it's likely because CounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterFnProps, and check that $CounterFnProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because CounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterFnProps, and check that $CounterFnProps is exported/imported properly.
+        $CounterFnProps,
         ModelCounterFnPropsMixin,
-        $ModelCounterFnPropsMixin // If this generated mixin is undefined, it's likely because ModelCounterFnPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ModelCounterFnPropsMixin, and check that $ModelCounterFnPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because ModelCounterFnPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ModelCounterFnPropsMixin, and check that $ModelCounterFnPropsMixin is exported/imported properly.
+        $ModelCounterFnPropsMixin
     implements
         ModelCounterFnProps {
   _$$ModelCounterFnProps._();
@@ -317,9 +319,11 @@ final UiFactoryConfig<_$$CustomContextCounterFnProps>
 abstract class _$$CustomContextCounterFnProps extends UiProps
     with
         CounterFnProps,
-        $CounterFnProps, // If this generated mixin is undefined, it's likely because CounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterFnProps, and check that $CounterFnProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because CounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterFnProps, and check that $CounterFnProps is exported/imported properly.
+        $CounterFnProps,
         CustomContextCounterFnPropsMixin,
-        $CustomContextCounterFnPropsMixin // If this generated mixin is undefined, it's likely because CustomContextCounterFnPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomContextCounterFnPropsMixin, and check that $CustomContextCounterFnPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because CustomContextCounterFnPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomContextCounterFnPropsMixin, and check that $CustomContextCounterFnPropsMixin is exported/imported properly.
+        $CustomContextCounterFnPropsMixin
     implements
         CustomContextCounterFnProps {
   _$$CustomContextCounterFnProps._();
diff --git a/test/over_react_redux/hooks/use_dispatch_test.over_react.g.dart b/test/over_react_redux/hooks/use_dispatch_test.over_react.g.dart
index 8e5c383d2..0bef8a7f0 100644
--- a/test/over_react_redux/hooks/use_dispatch_test.over_react.g.dart
+++ b/test/over_react_redux/hooks/use_dispatch_test.over_react.g.dart
@@ -68,8 +68,8 @@ final UiFactoryConfig<_$$UseDispatchCounterFnProps>
 abstract class _$$UseDispatchCounterFnProps extends UiProps
     with
         UseDispatchCounterFnProps,
-        $UseDispatchCounterFnProps // If this generated mixin is undefined, it's likely because UseDispatchCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of UseDispatchCounterFnProps, and check that $UseDispatchCounterFnProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because UseDispatchCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of UseDispatchCounterFnProps, and check that $UseDispatchCounterFnProps is exported/imported properly.
+        $UseDispatchCounterFnProps {
   _$$UseDispatchCounterFnProps._();
 
   factory _$$UseDispatchCounterFnProps(Map backingMap) {
@@ -157,8 +157,8 @@ final UiFactoryConfig<_$$CustomContextUseDispatchCounterFnProps>
 abstract class _$$CustomContextUseDispatchCounterFnProps extends UiProps
     with
         CustomContextUseDispatchCounterFnProps,
-        $CustomContextUseDispatchCounterFnProps // If this generated mixin is undefined, it's likely because CustomContextUseDispatchCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomContextUseDispatchCounterFnProps, and check that $CustomContextUseDispatchCounterFnProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because CustomContextUseDispatchCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomContextUseDispatchCounterFnProps, and check that $CustomContextUseDispatchCounterFnProps is exported/imported properly.
+        $CustomContextUseDispatchCounterFnProps {
   _$$CustomContextUseDispatchCounterFnProps._();
 
   factory _$$CustomContextUseDispatchCounterFnProps(Map backingMap) {
diff --git a/test/over_react_redux/hooks/use_store_test.over_react.g.dart b/test/over_react_redux/hooks/use_store_test.over_react.g.dart
index 68a084aac..848968ec4 100644
--- a/test/over_react_redux/hooks/use_store_test.over_react.g.dart
+++ b/test/over_react_redux/hooks/use_store_test.over_react.g.dart
@@ -68,8 +68,8 @@ final UiFactoryConfig<_$$UseStoreCounterFnProps> $UseStoreCounterFnConfig =
 abstract class _$$UseStoreCounterFnProps extends UiProps
     with
         UseStoreCounterFnProps,
-        $UseStoreCounterFnProps // If this generated mixin is undefined, it's likely because UseStoreCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of UseStoreCounterFnProps, and check that $UseStoreCounterFnProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because UseStoreCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of UseStoreCounterFnProps, and check that $UseStoreCounterFnProps is exported/imported properly.
+        $UseStoreCounterFnProps {
   _$$UseStoreCounterFnProps._();
 
   factory _$$UseStoreCounterFnProps(Map backingMap) {
@@ -156,8 +156,8 @@ final UiFactoryConfig<_$$CustomContextUseStoreCounterFnProps>
 abstract class _$$CustomContextUseStoreCounterFnProps extends UiProps
     with
         CustomContextUseStoreCounterFnProps,
-        $CustomContextUseStoreCounterFnProps // If this generated mixin is undefined, it's likely because CustomContextUseStoreCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomContextUseStoreCounterFnProps, and check that $CustomContextUseStoreCounterFnProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because CustomContextUseStoreCounterFnProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CustomContextUseStoreCounterFnProps, and check that $CustomContextUseStoreCounterFnProps is exported/imported properly.
+        $CustomContextUseStoreCounterFnProps {
   _$$CustomContextUseStoreCounterFnProps._();
 
   factory _$$CustomContextUseStoreCounterFnProps(Map backingMap) {
diff --git a/test/over_react_redux/store_bindings_tests.over_react.g.dart b/test/over_react_redux/store_bindings_tests.over_react.g.dart
index 3bd6939f2..6d2d41407 100644
--- a/test/over_react_redux/store_bindings_tests.over_react.g.dart
+++ b/test/over_react_redux/store_bindings_tests.over_react.g.dart
@@ -109,8 +109,8 @@ final UiFactoryConfig<_$$TestSelectorProps> $TestSelectorConfig =
 abstract class _$$TestSelectorProps extends UiProps
     with
         TestSelectorProps,
-        $TestSelectorProps // If this generated mixin is undefined, it's likely because TestSelectorProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSelectorProps, and check that $TestSelectorProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because TestSelectorProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSelectorProps, and check that $TestSelectorProps is exported/imported properly.
+        $TestSelectorProps {
   _$$TestSelectorProps._();
 
   factory _$$TestSelectorProps(Map backingMap) {
@@ -195,9 +195,11 @@ final UiFactoryConfig<_$$TestConnectProps> $TestConnectMapViewConfig =
 abstract class _$$TestConnectProps extends UiProps
     with
         TestSelectorProps,
-        $TestSelectorProps, // If this generated mixin is undefined, it's likely because TestSelectorProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSelectorProps, and check that $TestSelectorProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TestSelectorProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestSelectorProps, and check that $TestSelectorProps is exported/imported properly.
+        $TestSelectorProps,
         TestConnectPropsMixin,
-        $TestConnectPropsMixin // If this generated mixin is undefined, it's likely because TestConnectPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestConnectPropsMixin, and check that $TestConnectPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because TestConnectPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of TestConnectPropsMixin, and check that $TestConnectPropsMixin is exported/imported properly.
+        $TestConnectPropsMixin
     implements
         TestConnectProps {
   _$$TestConnectProps._();
diff --git a/test/vm_tests/builder/parsing/ast_util_test.dart b/test/vm_tests/builder/parsing/ast_util_test.dart
index 863a09a1b..acaccfca0 100644
--- a/test/vm_tests/builder/parsing/ast_util_test.dart
+++ b/test/vm_tests/builder/parsing/ast_util_test.dart
@@ -188,43 +188,43 @@ main() {
 
     group('AbstractGetter', () {
       test('hasAbstractGetter', () {
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             String get foo;
           }
         ''')).hasAbstractGetter('String', 'foo'), isTrue);
 
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             Generic<String> get foo;
           }
         ''')).hasAbstractGetter('Generic<String>', 'foo'), isTrue);
 
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             String get foo => 'impl';
           }
         ''')).hasAbstractGetter('String', 'foo'), isFalse);
 
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             WrongType get foo;
           }
         ''')).hasAbstractGetter('String', 'foo'), isFalse);
 
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             String get wrongName;
           }
         ''')).hasAbstractGetter('String', 'foo'), isFalse);
 
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             String foo;
           }
         ''')).hasAbstractGetter('String', 'foo'), isFalse);
 
-        expect(AbstractGetter(parseAndGetSingleWithType('''
+        expect(AbstractGetter(parseAndGetSingleClassish('''
           abstract class Foo {
             set foo(String value);
           }
diff --git a/test/vm_tests/builder/parsing/error_collection.dart b/test/vm_tests/builder/parsing/error_collection_test.dart
similarity index 99%
rename from test/vm_tests/builder/parsing/error_collection.dart
rename to test/vm_tests/builder/parsing/error_collection_test.dart
index 2426293db..3fdadc6e0 100644
--- a/test/vm_tests/builder/parsing/error_collection.dart
+++ b/test/vm_tests/builder/parsing/error_collection_test.dart
@@ -97,7 +97,7 @@ main() {
           test('when the unit is a SyntacticEntity', () {
             final localFileParseResult = parseString(content: boilerplateString);
             final propsNameToken = localFileParseResult.unit.childEntities
-                .whereType<ClassOrMixinDeclaration>()
+                .whereType<ClassDeclaration>()
                 .first
                 .name;
 
diff --git a/test/vm_tests/builder/parsing/members_test.dart b/test/vm_tests/builder/parsing/members_test.dart
index 93db26069..7a22f3b8d 100644
--- a/test/vm_tests/builder/parsing/members_test.dart
+++ b/test/vm_tests/builder/parsing/members_test.dart
@@ -1100,7 +1100,7 @@ main() {
             final members = BoilerplateMemberHelper.parseAndReturnMembers(boilerplateString);
             final props = members.whereType<BoilerplatePropsMixin>().first;
 
-            checkForMetaPresence(props.node, collector);
+            checkForMetaPresence(props.node.asClassish(), collector);
             expect(errorList, []);
             expect(warnList, []);
           });
@@ -1131,7 +1131,7 @@ main() {
             final members = BoilerplateMemberHelper.parseAndReturnMembers(boilerplateString);
             final props = members.whereType<BoilerplatePropsMixin>().first;
 
-            checkForMetaPresence(props.node, collector);
+            checkForMetaPresence(props.node.asClassish(), collector);
             expect(errorList, []);
             expect(warnList, [
               stringContainsInOrder(['Static class member `meta` is declared in FooProps']),
@@ -1164,7 +1164,7 @@ main() {
             final members = BoilerplateMemberHelper.parseAndReturnMembers(boilerplateString);
             final props = members.whereType<BoilerplatePropsMixin>().first;
 
-            checkForMetaPresence(props.node, collector);
+            checkForMetaPresence(props.node.asClassish(), collector);
             expect(errorList, [
               stringContainsInOrder(['Non-static class member `meta` is declared in FooProps']),
             ]);
diff --git a/test_fixtures/gold_output_files/mixin_based/basic.over_react.g.dart.goldFile b/test_fixtures/gold_output_files/mixin_based/basic.over_react.g.dart.goldFile
index 1c89197ef..bd1740531 100644
--- a/test_fixtures/gold_output_files/mixin_based/basic.over_react.g.dart.goldFile
+++ b/test_fixtures/gold_output_files/mixin_based/basic.over_react.g.dart.goldFile
@@ -32,8 +32,8 @@ _$$BasicProps _$Basic([Map backingProps]) => backingProps == null
 abstract class _$$BasicProps extends UiProps
     with
         BasicProps,
-        $BasicProps // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
+        $BasicProps {
   _$$BasicProps._();
 
   factory _$$BasicProps(Map backingMap) {
diff --git a/test_fixtures/gold_output_files/mixin_based/basic_library.over_react.g.dart.goldFile b/test_fixtures/gold_output_files/mixin_based/basic_library.over_react.g.dart.goldFile
index 9c24a163e..fa25b2311 100644
--- a/test_fixtures/gold_output_files/mixin_based/basic_library.over_react.g.dart.goldFile
+++ b/test_fixtures/gold_output_files/mixin_based/basic_library.over_react.g.dart.goldFile
@@ -33,9 +33,11 @@ _$$BasicPartOfLibProps _$BasicPartOfLib([Map backingProps]) =>
 abstract class _$$BasicPartOfLibProps extends UiProps
     with
         ExamplePropsMixin,
-        $ExamplePropsMixin, // If this generated mixin is undefined, it's likely because ExamplePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExamplePropsMixin, and check that $ExamplePropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because ExamplePropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ExamplePropsMixin, and check that $ExamplePropsMixin is exported/imported properly.
+        $ExamplePropsMixin,
         BasicPartOfLibPropsMixin,
-        $BasicPartOfLibPropsMixin // If this generated mixin is undefined, it's likely because BasicPartOfLibPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicPartOfLibPropsMixin, and check that $BasicPartOfLibPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because BasicPartOfLibPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicPartOfLibPropsMixin, and check that $BasicPartOfLibPropsMixin is exported/imported properly.
+        $BasicPartOfLibPropsMixin
     implements
         BasicPartOfLibProps {
   _$$BasicPartOfLibProps._();
@@ -115,9 +117,11 @@ class _$$BasicPartOfLibProps$JsMap extends _$$BasicPartOfLibProps {
 abstract class _$$BasicPartOfLibState extends UiState
     with
         ExampleStateMixin,
-        $ExampleStateMixin, // If this generated mixin is undefined, it's likely because ExampleStateMixin is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of ExampleStateMixin, and check that $ExampleStateMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because ExampleStateMixin is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of ExampleStateMixin, and check that $ExampleStateMixin is exported/imported properly.
+        $ExampleStateMixin,
         BasicPartOfLibStateMixin,
-        $BasicPartOfLibStateMixin // If this generated mixin is undefined, it's likely because BasicPartOfLibStateMixin is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicPartOfLibStateMixin, and check that $BasicPartOfLibStateMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because BasicPartOfLibStateMixin is not a valid `mixin`-based state mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicPartOfLibStateMixin, and check that $BasicPartOfLibStateMixin is exported/imported properly.
+        $BasicPartOfLibStateMixin
     implements
         BasicPartOfLibState {
   _$$BasicPartOfLibState._();
@@ -400,9 +404,11 @@ _$$SubPartOfLibProps _$SubPartOfLib([Map backingProps]) => backingProps == null
 abstract class _$$SubPartOfLibProps extends UiProps
     with
         SuperPartOfLibPropsMixin,
-        $SuperPartOfLibPropsMixin, // If this generated mixin is undefined, it's likely because SuperPartOfLibPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SuperPartOfLibPropsMixin, and check that $SuperPartOfLibPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SuperPartOfLibPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SuperPartOfLibPropsMixin, and check that $SuperPartOfLibPropsMixin is exported/imported properly.
+        $SuperPartOfLibPropsMixin,
         SubPartOfLibPropsMixin,
-        $SubPartOfLibPropsMixin // If this generated mixin is undefined, it's likely because SubPartOfLibPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SubPartOfLibPropsMixin, and check that $SubPartOfLibPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SubPartOfLibPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SubPartOfLibPropsMixin, and check that $SubPartOfLibPropsMixin is exported/imported properly.
+        $SubPartOfLibPropsMixin
     implements
         SubPartOfLibProps {
   _$$SubPartOfLibProps._();
diff --git a/test_fixtures/gold_output_files/mixin_based/basic_two_nine.over_react.g.dart.goldFile b/test_fixtures/gold_output_files/mixin_based/basic_two_nine.over_react.g.dart.goldFile
index fe14a011d..212c22517 100644
--- a/test_fixtures/gold_output_files/mixin_based/basic_two_nine.over_react.g.dart.goldFile
+++ b/test_fixtures/gold_output_files/mixin_based/basic_two_nine.over_react.g.dart.goldFile
@@ -32,8 +32,8 @@ _$$BasicProps _$Basic([Map backingProps]) => backingProps == null
 abstract class _$$BasicProps extends UiProps
     with
         BasicProps,
-        $BasicProps // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because BasicProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of BasicProps, and check that $BasicProps is exported/imported properly.
+        $BasicProps {
   _$$BasicProps._();
 
   factory _$$BasicProps(Map backingMap) {
diff --git a/test_fixtures/gold_output_files/mixin_based/two_nine_with_multiple_factories.over_react.g.dart.goldfile b/test_fixtures/gold_output_files/mixin_based/two_nine_with_multiple_factories.over_react.g.dart.goldfile
index a4c3dbb63..223d765f2 100644
--- a/test_fixtures/gold_output_files/mixin_based/two_nine_with_multiple_factories.over_react.g.dart.goldfile
+++ b/test_fixtures/gold_output_files/mixin_based/two_nine_with_multiple_factories.over_react.g.dart.goldfile
@@ -32,9 +32,11 @@ _$$CounterProps _$_Counter([Map backingProps]) => backingProps == null
 abstract class _$$CounterProps extends UiProps
     with
         CounterPropsMixin,
-        $CounterPropsMixin, // If this generated mixin is undefined, it's likely because CounterPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterPropsMixin, and check that $CounterPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because CounterPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of CounterPropsMixin, and check that $CounterPropsMixin is exported/imported properly.
+        $CounterPropsMixin,
         ConnectPropsMixin,
-        $ConnectPropsMixin // If this generated mixin is undefined, it's likely because ConnectPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ConnectPropsMixin, and check that $ConnectPropsMixin is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because ConnectPropsMixin is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of ConnectPropsMixin, and check that $ConnectPropsMixin is exported/imported properly.
+        $ConnectPropsMixin
     implements
         CounterProps {
   _$$CounterProps._();
diff --git a/test_fixtures/gold_output_files/mixin_based/type_parameters.over_react.g.dart.goldFile b/test_fixtures/gold_output_files/mixin_based/type_parameters.over_react.g.dart.goldFile
index 3e82e2413..cb813d062 100644
--- a/test_fixtures/gold_output_files/mixin_based/type_parameters.over_react.g.dart.goldFile
+++ b/test_fixtures/gold_output_files/mixin_based/type_parameters.over_react.g.dart.goldFile
@@ -174,9 +174,8 @@ _$$SingleProps _$Single([Map backingProps]) => backingProps == null
 abstract class _$$SingleProps<T> extends UiProps
     with
         SingleProps<T>,
-        $SingleProps<
-            T> // If this generated mixin is undefined, it's likely because SingleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleProps, and check that $SingleProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because SingleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleProps, and check that $SingleProps is exported/imported properly.
+        $SingleProps<T> {
   _$$SingleProps._();
 
   factory _$$SingleProps(Map backingMap) {
@@ -252,9 +251,8 @@ _$$SingleWithBoundProps _$SingleWithBound([Map backingProps]) =>
 abstract class _$$SingleWithBoundProps<S extends Pattern> extends UiProps
     with
         SingleWithBoundProps<S>,
-        $SingleWithBoundProps<
-            S> // If this generated mixin is undefined, it's likely because SingleWithBoundProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleWithBoundProps, and check that $SingleWithBoundProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because SingleWithBoundProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleWithBoundProps, and check that $SingleWithBoundProps is exported/imported properly.
+        $SingleWithBoundProps<S> {
   _$$SingleWithBoundProps._();
 
   factory _$$SingleWithBoundProps(Map backingMap) {
@@ -331,9 +329,8 @@ _$$DoubleProps _$Double([Map backingProps]) => backingProps == null
 abstract class _$$DoubleProps<A, B> extends UiProps
     with
         DoubleProps<A, B>,
-        $DoubleProps<A,
-            B> // If this generated mixin is undefined, it's likely because DoubleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoubleProps, and check that $DoubleProps is exported/imported properly.
-{
+        // If this generated mixin is undefined, it's likely because DoubleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoubleProps, and check that $DoubleProps is exported/imported properly.
+        $DoubleProps<A, B> {
   _$$DoubleProps._();
 
   factory _$$DoubleProps(Map backingMap) {
@@ -408,18 +405,20 @@ _$$ConcreteNoneProps _$ConcreteNone([Map backingProps]) => backingProps == null
 abstract class _$$ConcreteNoneProps extends UiProps
     with
         NoneProps,
-        $NoneProps, // If this generated mixin is undefined, it's likely because NoneProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of NoneProps, and check that $NoneProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because NoneProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of NoneProps, and check that $NoneProps is exported/imported properly.
+        $NoneProps,
         SingleProps<String>,
-        $SingleProps<
-            String>, // If this generated mixin is undefined, it's likely because SingleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleProps, and check that $SingleProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SingleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleProps, and check that $SingleProps is exported/imported properly.
+        $SingleProps<String>,
         SingleThatWontBeSpecifiedProps,
-        $SingleThatWontBeSpecifiedProps, // If this generated mixin is undefined, it's likely because SingleThatWontBeSpecifiedProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleThatWontBeSpecifiedProps, and check that $SingleThatWontBeSpecifiedProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SingleThatWontBeSpecifiedProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleThatWontBeSpecifiedProps, and check that $SingleThatWontBeSpecifiedProps is exported/imported properly.
+        $SingleThatWontBeSpecifiedProps,
         SingleWithBoundProps<RegExp>,
-        $SingleWithBoundProps<
-            RegExp>, // If this generated mixin is undefined, it's likely because SingleWithBoundProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleWithBoundProps, and check that $SingleWithBoundProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SingleWithBoundProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleWithBoundProps, and check that $SingleWithBoundProps is exported/imported properly.
+        $SingleWithBoundProps<RegExp>,
         DoubleProps<double, int>,
-        $DoubleProps<double,
-            int> // If this generated mixin is undefined, it's likely because DoubleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoubleProps, and check that $DoubleProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because DoubleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoubleProps, and check that $DoubleProps is exported/imported properly.
+        $DoubleProps<double, int>
     implements
         ConcreteNoneProps {
   _$$ConcreteNoneProps._();
@@ -504,18 +503,20 @@ _$$ConcreteArgsProps _$ConcreteArgs([Map backingProps]) => backingProps == null
 abstract class _$$ConcreteArgsProps<U, V extends Iterable> extends UiProps
     with
         NoneProps,
-        $NoneProps, // If this generated mixin is undefined, it's likely because NoneProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of NoneProps, and check that $NoneProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because NoneProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of NoneProps, and check that $NoneProps is exported/imported properly.
+        $NoneProps,
         SingleProps<String>,
-        $SingleProps<
-            String>, // If this generated mixin is undefined, it's likely because SingleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleProps, and check that $SingleProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SingleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleProps, and check that $SingleProps is exported/imported properly.
+        $SingleProps<String>,
         SingleThatWontBeSpecifiedProps,
-        $SingleThatWontBeSpecifiedProps, // If this generated mixin is undefined, it's likely because SingleThatWontBeSpecifiedProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleThatWontBeSpecifiedProps, and check that $SingleThatWontBeSpecifiedProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SingleThatWontBeSpecifiedProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleThatWontBeSpecifiedProps, and check that $SingleThatWontBeSpecifiedProps is exported/imported properly.
+        $SingleThatWontBeSpecifiedProps,
         SingleWithBoundProps<RegExp>,
-        $SingleWithBoundProps<
-            RegExp>, // If this generated mixin is undefined, it's likely because SingleWithBoundProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleWithBoundProps, and check that $SingleWithBoundProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because SingleWithBoundProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of SingleWithBoundProps, and check that $SingleWithBoundProps is exported/imported properly.
+        $SingleWithBoundProps<RegExp>,
         DoubleProps<U, V>,
-        $DoubleProps<U,
-            V> // If this generated mixin is undefined, it's likely because DoubleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoubleProps, and check that $DoubleProps is exported/imported properly.
+        // If this generated mixin is undefined, it's likely because DoubleProps is not a valid `mixin`-based props mixin, or because it is but the generated mixin was not imported. Check the declaration of DoubleProps, and check that $DoubleProps is exported/imported properly.
+        $DoubleProps<U, V>
     implements
         ConcreteArgsProps<U, V> {
   _$$ConcreteArgsProps._();
diff --git a/tools/analyzer_plugin/analysis_options.yaml b/tools/analyzer_plugin/analysis_options.yaml
index c1040a326..cac19697a 100644
--- a/tools/analyzer_plugin/analysis_options.yaml
+++ b/tools/analyzer_plugin/analysis_options.yaml
@@ -3,6 +3,7 @@ include: package:workiva_analysis_options/v1.recommended.yaml
 analyzer:
   exclude:
     - playground/**
+    - test/test_fixtures/**
   strong-mode:
     implicit-casts: false
     implicit-dynamic: false
@@ -14,6 +15,7 @@ analyzer:
     # Override workiva_analysis_options upgrade to warning
     unused_import: info
     import_of_legacy_library_into_null_safe: warning
+    implementation_imports: warning
 
     # ignores from v1.recommended
     prefer_interpolation_to_compose_strings: ignore
@@ -28,3 +30,4 @@ linter:
   rules:
     - avoid_returning_null_for_future
     - avoid_void_async
+    - implementation_imports
diff --git a/tools/analyzer_plugin/lib/src/assist/convert_class_or_function_component.dart b/tools/analyzer_plugin/lib/src/assist/convert_class_or_function_component.dart
index 3e78d756a..c3590ea06 100644
--- a/tools/analyzer_plugin/lib/src/assist/convert_class_or_function_component.dart
+++ b/tools/analyzer_plugin/lib/src/assist/convert_class_or_function_component.dart
@@ -45,9 +45,9 @@ class ConvertClassOrFunctionComponentAssistContributor extends AssistContributor
   Future<void> _tryConvertClassComponent(ClassDeclaration closestClass) async {
     // todo use over_react builders' boilerplate parsing to get the associated factory and config instead of this logic
 
-    if (!closestClass.name.name.endsWith('Component')) return;
+    if (!closestClass.name.lexeme.endsWith('Component')) return;
 
-    final name = closestClass.name.name.substring(0, closestClass.name.name.length - 'Component'.length);
+    final name = closestClass.name.lexeme.substring(0, closestClass.name.lexeme.length - 'Component'.length);
     final generatedFactoryConfigName = '_\$${name}Config';
 
     final factory = node
@@ -55,7 +55,7 @@ class ConvertClassOrFunctionComponentAssistContributor extends AssistContributor
         ?.declarations
         .whereType<TopLevelVariableDeclaration>()
         .expand((element) => element.variables.variables)
-        .firstWhere((element) => element.name.name == name);
+        .firstWhere((element) => element.name.lexeme == name);
     if (factory == null) return;
 
     final factoryDecl = factory.thisOrAncestorOfType<TopLevelVariableDeclaration>()!;
@@ -65,7 +65,7 @@ class ConvertClassOrFunctionComponentAssistContributor extends AssistContributor
 
     // todo migrate defaults?
 
-    final render = closestClass.members.whereType<MethodDeclaration>().firstWhereOrNull((m) => m.name.name == 'render');
+    final render = closestClass.members.whereType<MethodDeclaration>().firstWhereOrNull((m) => m.name.lexeme == 'render');
     if (render == null) return;
 
     final renderBody = render.body;
@@ -137,7 +137,7 @@ class ConvertClassOrFunctionComponentAssistContributor extends AssistContributor
 
     // todo use over_react builders' boilerplate parsing to get the associated factory and name of assiciated props class instead of this logic
 
-    final name = factory.name.name;
+    final name = factory.name.lexeme;
     final componentClassName = '${name}Component';
     final generatedFactoryName = '_\$$name';
     final propsClassName = '${name}Props';
@@ -159,7 +159,7 @@ class ConvertClassOrFunctionComponentAssistContributor extends AssistContributor
                   .thisOrAncestorOfType<CompilationUnit>()
                   ?.declarations
                   .whereType<NamedCompilationUnitMember>()
-                  .firstWhereOrNull((element) => element.name.name == propsClassName) ??
+                  .firstWhereOrNull((element) => element.name.lexeme == propsClassName) ??
               factoryInitializer.thisOrAncestorOfType<CompilationUnitMember>()!)
           .end;
 
diff --git a/tools/analyzer_plugin/lib/src/assist/refs/add_create_ref.dart b/tools/analyzer_plugin/lib/src/assist/refs/add_create_ref.dart
index c7d0db325..e3ccd73de 100644
--- a/tools/analyzer_plugin/lib/src/assist/refs/add_create_ref.dart
+++ b/tools/analyzer_plugin/lib/src/assist/refs/add_create_ref.dart
@@ -209,7 +209,7 @@ Pair<int, AstNode> _getRefInsertionLocation(AstNode node, LineInfo lineInfo) {
         child.tryCast<TopLevelVariableDeclaration>()?.variables ??
         child.tryCast<VariableDeclarationStatement>()?.variables;
     if (variables != null &&
-        variables.variables.any((decl) => decl.name.name != 'Ref' && decl.name.name.endsWith('Ref'))) {
+        variables.variables.any((decl) => decl.name.lexeme != 'Ref' && decl.name.lexeme.endsWith('Ref'))) {
       offset = nextLine(child.end, lineInfo);
       break;
     }
diff --git a/tools/analyzer_plugin/lib/src/async_plugin_apis/diagnostic.dart b/tools/analyzer_plugin/lib/src/async_plugin_apis/diagnostic.dart
index 208228a23..bc4d43eda 100644
--- a/tools/analyzer_plugin/lib/src/async_plugin_apis/diagnostic.dart
+++ b/tools/analyzer_plugin/lib/src/async_plugin_apis/diagnostic.dart
@@ -32,6 +32,7 @@
 
 import 'dart:async';
 
+import 'package:analyzer/dart/analysis/analysis_context.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer_plugin/channel/channel.dart';
 import 'package:analyzer_plugin/plugin/plugin.dart';
@@ -41,7 +42,7 @@ import 'package:analyzer_plugin/protocol/protocol_generated.dart' as plugin;
 import 'package:analyzer_plugin/protocol/protocol_generated.dart';
 
 // ignore: implementation_imports
-import 'package:analyzer_plugin/src/utilities/fixes/fixes.dart';
+import 'package:analyzer_plugin/src/utilities/fixes/fixes.dart' show DartFixesRequestImpl;
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:meta/meta.dart';
 import 'package:over_react_analyzer_plugin/src/async_plugin_apis/error_severity_provider.dart';
@@ -56,24 +57,20 @@ import 'package:over_react_analyzer_plugin/src/util/pretty_print.dart';
 mixin DiagnosticMixin on ServerPlugin {
   PluginOptionsReader get pluginOptionsReader;
 
-  List<DiagnosticContributor> getDiagnosticContributors(String path);
-
-  /// Computes errors based on an analysis result and notifies the analyzer.
-  Future<void> processDiagnosticsForResult(ResolvedUnitResult analysisResult) async {
-    await getAllErrors(analysisResult);
-  }
+  List<DiagnosticContributor> getDiagnosticContributors(AnalysisContext analysisContext, String path);
 
   /// Computes errors based on an analysis result, notifies the analyzer, and
   /// then returns the list of errors.
   Future<List<AnalysisError>> getAllErrors(ResolvedUnitResult analysisResult) async {
-    final analysisOptions = pluginOptionsReader.getOptionsForResult(analysisResult);
+    final analysisContext = analysisResult.session.analysisContext;
+    final analysisOptions = pluginOptionsReader.getOptionsForContextRoot(analysisContext.contextRoot);
 
     try {
       // If there is something to analyze, do so and notify the analyzer.
       // Note that notifying with an empty set of errors is important as
       // this clears errors if they were fixed.
       final generator = _DiagnosticGenerator(
-        getDiagnosticContributors(analysisResult.path),
+        getDiagnosticContributors(analysisContext, analysisResult.path),
         errorSeverityProvider: AnalysisOptionsErrorSeverityProvider(analysisOptions),
       );
       final result = await generator.generateErrors(analysisResult);
@@ -91,11 +88,12 @@ mixin DiagnosticMixin on ServerPlugin {
   Future<plugin.EditGetFixesResult> handleEditGetFixes(plugin.EditGetFixesParams parameters) async {
     // We want request errors to propagate if they throw
     final request = await _getFixesRequest(parameters);
-    final analysisOptions = pluginOptionsReader.getOptionsForResult(request.result);
+    final analysisContext = request.result.session.analysisContext;
+    final analysisOptions = pluginOptionsReader.getOptionsForContextRoot(analysisContext.contextRoot);
 
     try {
       final generator = _DiagnosticGenerator(
-        getDiagnosticContributors(parameters.file),
+        getDiagnosticContributors(analysisContext, parameters.file),
         errorSeverityProvider: AnalysisOptionsErrorSeverityProvider(analysisOptions),
       );
       final result = await generator.generateFixesResponse(request);
diff --git a/tools/analyzer_plugin/lib/src/component_usage.dart b/tools/analyzer_plugin/lib/src/component_usage.dart
index 450b5ddce..55bb09dba 100644
--- a/tools/analyzer_plugin/lib/src/component_usage.dart
+++ b/tools/analyzer_plugin/lib/src/component_usage.dart
@@ -71,7 +71,7 @@ class FluentComponentUsage {
 
   /// The class element for the builder's props class (or, for parameterized types
   /// the bound of that type), or `null` if this usage is not fully resolved.
-  ClassElement? get propsClassElement => builderType?.typeOrBound.tryCast<InterfaceType>()?.element;
+  InterfaceElement? get propsClassElement => builderType?.typeOrBound.tryCast<InterfaceType>()?.element;
 
   /// The name of the builder's props class (or, for parameterized types
   /// the bound of that type), or `null` if this usage is not fully resolved.
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/bad_key.dart b/tools/analyzer_plugin/lib/src/diagnostic/bad_key.dart
index 43cc1f1f4..f32329a78 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/bad_key.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/bad_key.dart
@@ -185,13 +185,15 @@ class BadKeyDiagnostic extends ComponentUsageDiagnosticContributor {
   }
 
   static bool inheritsToStringImplFromObject(Element element) =>
-      element
-          .tryCast<ClassElement>()
+      // Enums have toStrings that include their name.
+      element is! EnumElement &&
+      (element
+          .tryCast<InterfaceElement>()
           ?.lookUpConcreteMethod('toString', element.library!)
-          ?.thisOrAncestorOfType<ClassElement>()
+          ?.thisOrAncestorOfType<InterfaceElement>()
           ?.thisType
           .isDartCoreObject ??
-      false;
+      false);
 }
 
 /// Recursively collects expressions that are used to effectively call `toString()`:
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/boilerplate_validator.dart b/tools/analyzer_plugin/lib/src/diagnostic/boilerplate_validator.dart
index a8a625a80..cd12e1329 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/boilerplate_validator.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/boilerplate_validator.dart
@@ -67,15 +67,15 @@ class BoilerplateValidatorDiagnostic extends DiagnosticContributor {
   PartDirective? _overReactGeneratedPartDirective;
   late bool _overReactGeneratedPartDirectiveIsValid;
 
-  /// Returns true if the [unit] representing a part file has declarations.
+  /// Returns true if the [unit] has over_react boilerplate declarations.
   ///
-  /// Does not report any errors for the part file, as those are handled when the part file is analyzed
-  bool _partHasDeclarations(CompilationUnit unit, ResolvedUnitResult parentResult) {
+  /// Does not report any errors for the unit, as those are handled when each unit is analyzed
+  bool _unitHasDeclarations(CompilationUnit unit, ParsedUnitResult unitResult) {
     return orbp
         .getBoilerplateDeclarations(
             orbp.detectBoilerplateMembers(unit),
             orbp.ErrorCollector.callback(
-              SourceFile.fromString(parentResult.content, url: parentResult.path),
+              SourceFile.fromString(unitResult.content, url: unitResult.path),
               // no-op for these.
               // It is assumed this method will run for parent files, and the part file will get analyzed in its own context.
               // Need types on the second args to avoid nullability errors, since they come from a non-null-safe library.
@@ -206,22 +206,15 @@ class BoilerplateValidatorDiagnostic extends DiagnosticContributor {
       return;
     }
 
-    final parts = getNonGeneratedParts(result.unit);
-
-    // compute errors for parts files
-    var anyPartHasDeclarations = false;
-    for (final part in parts) {
-      final uri = part.uriSource?.uri;
-      // URI could not be resolved or source does not exist
-      if (uri == null) continue;
-      final partResult = result.session.getParsedUnit(result.session.uriConverter.uriToPath(uri)!);
-
-      if (partResult is ParsedUnitResult && _partHasDeclarations(partResult.unit, result)) {
-        anyPartHasDeclarations = true;
-      }
-    }
-
-    await _computePartDirectiveErrors(result, collector, hasDeclarations || anyPartHasDeclarations);
+    // Compute errors related to part directives.
+    final anyUnitHasDeclarations = hasDeclarations || result.libraryElement.units.any((unit) {
+      final path = result.session.uriConverter.uriToPath(unit.source.uri);
+      if (path == null) return false;
+      final unitResult = result.session.getParsedUnit(path);
+      if (unitResult is! ParsedUnitResult) return false;
+      return _unitHasDeclarations(unitResult.unit, unitResult);
+    });
+    await _computePartDirectiveErrors(result, collector, anyUnitHasDeclarations);
   }
 
   Future<void> _addPartDirectiveErrorForMember({
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/bool_prop_name_readability.dart b/tools/analyzer_plugin/lib/src/diagnostic/bool_prop_name_readability.dart
index 71d77609b..3f0960871 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/bool_prop_name_readability.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/bool_prop_name_readability.dart
@@ -3,6 +3,8 @@ import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic_contributor.dart';
 import 'package:over_react_analyzer_plugin/src/util/react_types.dart';
 
+import '../util/util.dart';
+
 const _desc = r'Name boolean props in a way that makes them easy to read and infer their purpose.';
 // <editor-fold desc="Documentation Details">
 const _details = r'''
@@ -44,24 +46,22 @@ class BoolPropNameReadabilityDiagnostic extends DiagnosticContributor {
   @override
   computeErrors(result, collector) async {
     final typeProvider = result.libraryElement.typeProvider;
-    final visitor = PropsVisitor();
+    final visitor = PropFieldVisitor();
 
     result.unit.accept(visitor);
 
-    final returnMixins = visitor.returnMixins;
-
-    for (final propsClass in returnMixins) {
-      final mixinFields = propsClass.declaredElement!.fields;
-      for (final field in mixinFields) {
-        final propName = field.name;
-        if (field.type != typeProvider.boolType) continue;
-
-        final fieldDecl = propsClass.getField(propName);
-        if (fieldDecl == null) continue;
-
-        final readability = checkBoolPropReadability(propName);
-        if (!readability.isReadable) {
-          collector.addError(code, result.locationFor(fieldDecl), errorMessageArgs: [propsClass.name, propName]);
+    for (final tuple in visitor.propFields) {
+      final propsClass = tuple.item1;
+      final fields = tuple.item2;
+      for (final field in fields) {
+        for (final variable in field.fields.variables) {
+          final propName = variable.name.lexeme;
+          if (variable.declaredElement?.type != typeProvider.boolType) continue;
+
+          final readability = checkBoolPropReadability(propName);
+          if (!readability.isReadable) {
+            collector.addError(code, result.locationFor(variable), errorMessageArgs: [propsClass.name, propName]);
+          }
         }
       }
     }
@@ -106,24 +106,28 @@ bool hasBooleanContain(String propName) {
   return propName.toLowerCase().contains(RegExp('(${allowedContainsForBoolProp.join("|")})'));
 }
 
-class PropsVisitor extends SimpleAstVisitor<void> {
-  List<ClassOrMixinDeclaration> returnMixins = [];
+
+class PropFieldVisitor extends SimpleAstVisitor<void> {
+  List<Tuple2<NamedCompilationUnitMember, List<FieldDeclaration>>> propFields = [];
   @override
   void visitCompilationUnit(CompilationUnit node) {
     node.visitChildren(this);
   }
 
+  static List<FieldDeclaration> _getPropFields(Iterable<ClassMember> members) =>
+      members.whereType<FieldDeclaration>().where((f) => !f.isStatic).toList();
+
   @override
   void visitClassDeclaration(ClassDeclaration node) {
     if (node.declaredElement?.isPropsClass ?? false) {
-      returnMixins.add(node);
+      propFields.add(Tuple2(node, _getPropFields(node.members)));
     }
   }
 
   @override
   void visitMixinDeclaration(MixinDeclaration node) {
     if (node.declaredElement?.isPropsClass ?? false) {
-      returnMixins.add(node);
+      propFields.add(Tuple2(node, _getPropFields(node.members)));
     }
   }
 }
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/consumed_props_return_value.dart b/tools/analyzer_plugin/lib/src/diagnostic/consumed_props_return_value.dart
index d32ec935b..7436d2843 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/consumed_props_return_value.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/consumed_props_return_value.dart
@@ -129,7 +129,7 @@ class ConsumedPropsVisitor extends SimpleAstVisitor<void> {
 
   @override
   void visitMethodDeclaration(MethodDeclaration node) {
-    if (node.name.name == 'consumedProps') {
+    if (node.name.lexeme == 'consumedProps') {
       consumedPropsDeclarations.add(node);
     }
   }
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/exhaustive_deps.dart b/tools/analyzer_plugin/lib/src/diagnostic/exhaustive_deps.dart
index b32f25776..04c5a7ea6 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/exhaustive_deps.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/exhaustive_deps.dart
@@ -576,11 +576,15 @@ class ExhaustiveDeps extends DiagnosticContributor {
       // Does this function capture any values
       // that are in pure scopes (aka render)?
       final referencedElements = resolvedReferencesWithin(fnNode.body);
-      for (final ref in referencedElements) {
-        if (isDeclaredInPureScope(ref.staticElement!) &&
-            // Stable values are fine though,
-            // although we won't check functions deeper.
-            !memoizedIsStableKnownHookValue(ref)) {
+      for (final referenceUnion in referencedElements) {
+        if (referenceUnion.switchCase(
+          (identifier) =>
+              isDeclaredInPureScope(identifier.staticElement!) &&
+              // Stable values are fine though,
+              // although we won't check functions deeper.
+              !memoizedIsStableKnownHookValue(identifier),
+          (_) => false,
+        )) {
           return false;
         }
       }
@@ -607,7 +611,7 @@ class ExhaustiveDeps extends DiagnosticContributor {
 
     // The original implementation needs to recurse to process references in child scopes,
     // but we can process all descendant references regardless of scope in one go.
-    for (final reference in resolvedReferencesWithin(callbackFunction)) {
+    for (final referenceUnion in resolvedReferencesWithin(callbackFunction)) {
       // debug(
       //     'reference.staticElement.ancestors: \n${prettyPrint(reference.staticElement.ancestors.map(elementDebugString).toList())}',
       //     reference);
@@ -618,57 +622,87 @@ class ExhaustiveDeps extends DiagnosticContributor {
       // Note that with the implementation of `resolvedReferencesWithin`,
       // this is also necessary to filter out references to properties on object.
 
-      final referenceElement = reference.staticElement;
+      final referenceElement = referenceUnion.switchCase(
+        (identifier) => identifier.staticElement,
+        (namedType) => namedType.element,
+      );
       if (referenceElement == null) continue;
 
       if (!isDeclaredInPureScope(referenceElement)) {
         continue;
       }
 
-      // Narrow the scope of a dependency if it is, say, a member expression.
-      // Then normalize the narrowed dependency.
-      final dependencyNode = getDependency(reference);
-      final isUsedAsCascadeTarget = dependencyNode.parent?.tryCast<CascadeExpression>()?.target == dependencyNode;
-      final dependency = analyzePropertyChain(
-        dependencyNode,
-        optionalChains,
-        isInvocationAllowedForNode: true,
+      // Use `late` because we're using Union.switchCase, meaning the analyzer can't ensure these variables
+      // are definitely assigned.
+      late String dependency;
+      late bool isStable;
+      late bool isUsedAsCascadeTarget;
+      referenceUnion.switchCase(
+        // Identifier case. This will be most refernces.
+        (reference) {
+          // Narrow the scope of a dependency if it is, say, a member expression.
+          // Then normalize the narrowed dependency.
+          final dependencyNode = getDependency(reference);
+          isUsedAsCascadeTarget = dependencyNode.parent?.tryCast<CascadeExpression>()?.target == dependencyNode;
+          dependency = analyzePropertyChain(
+            dependencyNode,
+            optionalChains,
+            isInvocationAllowedForNode: true,
+          );
+          isStable =
+              memoizedIsStableKnownHookValue(reference) || memoizedIsFunctionWithoutCapturedValues(referenceElement);
+
+          debug(() {
+            return prettyPrint({
+              'dependency': dependency,
+              'dependencyNode': '${dependencyNode.runtimeType} $dependencyNode',
+              'reference': '${reference.runtimeType} $reference',
+              'isUsedAsCascadeTarget': isUsedAsCascadeTarget,
+            });
+          }, dependencyNode);
+
+          // Accessing ref.current inside effect cleanup is bad.
+          if (
+              // We're in an effect...
+              isEffect &&
+                  // ... and this look like accessing .current...
+                  dependencyNode is Identifier &&
+                  getNonCascadedPropertyBeingAccessed(dependencyNode.parent)?.name == 'current' &&
+                  // ...in a cleanup function or below...
+                  isInsideEffectCleanup(reference)) {
+            currentRefsInEffectCleanup[dependency] = _RefInEffectCleanup(
+              reference: reference,
+              referenceElement: referenceElement,
+            );
+          }
+        },
+        // NamedType case. This is for references to generic type parameters
+        // (references to other types will get filtered out by the isDeclaredInPureScope check above).
+        (reference) {
+          dependency = reference.name.name;
+          // These aren't possible for type annotations.
+          isStable = false;
+          isUsedAsCascadeTarget = false;
+
+          debug(() {
+            return prettyPrint({
+              'dependency': dependency,
+              'reference': '${reference.runtimeType} $reference',
+            });
+          }, reference);
+        },
       );
-      debug(() {
-        return prettyPrint({
-          'dependency': dependency,
-          'dependencyNode': '${dependencyNode.runtimeType} $dependencyNode',
-          'reference': '${reference.runtimeType} $reference',
-          'isUsedAsCascadeTarget': isUsedAsCascadeTarget,
-        });
-      }, dependencyNode);
-
-      // Accessing ref.current inside effect cleanup is bad.
-      if (
-          // We're in an effect...
-          isEffect &&
-              // ... and this look like accessing .current...
-              dependencyNode is Identifier &&
-              getNonCascadedPropertyBeingAccessed(dependencyNode.parent)?.name == 'current' &&
-              // ...in a cleanup function or below...
-              isInsideEffectCleanup(reference)) {
-        currentRefsInEffectCleanup[dependency] = _RefInEffectCleanup(
-          reference: reference,
-          referenceElement: referenceElement,
-        );
-      }
 
       // Add the dependency to a map so we can make sure it is referenced
       // again in our dependencies array. Remember whether it's stable.
       dependencies.putIfAbsent(dependency, () {
         return _Dependency(
-          isStable:
-              memoizedIsStableKnownHookValue(reference) || memoizedIsFunctionWithoutCapturedValues(referenceElement),
+          isStable: isStable,
           references: [],
         );
       })
         // Note that for the the `state.set` case, the reference is still `state`.
-        ..references.add(reference)
+        ..references.add(referenceUnion)
         ..isUsedSomewhereAsCascadeTarget |= isUsedAsCascadeTarget;
     }
 
@@ -732,10 +766,10 @@ class ExhaustiveDeps extends DiagnosticContributor {
       if (dep.isStable) {
         stableDependencies.add(key);
       }
-      for (final reference in dep.references) {
-        final parent = reference.parent;
+      for (final referenceUnion in dep.references) {
+        final parent = referenceUnion.either.parent;
         // TODO(greg) make a utility to check for assignments
-        if (parent is AssignmentExpression && parent.leftHandSide == reference) {
+        if (parent is AssignmentExpression && parent.leftHandSide == referenceUnion.either) {
           reportStaleAssignment(parent, key);
         }
       }
@@ -755,17 +789,18 @@ class ExhaustiveDeps extends DiagnosticContributor {
         if (setStateInsideEffectWithoutDeps != null) {
           return;
         }
-        for (final reference in references) {
+        for (final referenceUnion in references) {
           if (setStateInsideEffectWithoutDeps != null) {
             continue;
           }
 
-          final isSetState = setStateCallSites.has(reference);
+          final isSetState = referenceUnion.switchCase(setStateCallSites.has, (_) => false);
           if (!isSetState) {
             continue;
           }
 
-          final isDirectlyInsideEffect = reference.thisOrAncestorOfType<FunctionBody>() == callbackFunction.body;
+          final isDirectlyInsideEffect =
+              referenceUnion.either.thisOrAncestorOfType<FunctionBody>() == callbackFunction.body;
           if (isDirectlyInsideEffect) {
             // TODO(ported): we could potentially ignore early returns.
             setStateInsideEffectWithoutDeps = key;
@@ -1080,7 +1115,7 @@ class ExhaustiveDeps extends DiagnosticContributor {
                   // This also preserves generic function expressions.
                   // `void something<T generic>(T arg) {…}` -> `final something = useCallback(<T>(T arg) {…}, […]);`
                   builder.addSimpleReplacement(range.startEnd(construction, construction.name),
-                      'final ${construction.name.name} = useCallback(');
+                      'final ${construction.name.lexeme} = useCallback(');
                   // TODO(ported): ideally we'd gather deps here but it would require
                   //  restructuring the rule code. Note we're
                   //  not adding [] because would that changes semantics.
@@ -1267,38 +1302,44 @@ class ExhaustiveDeps extends DiagnosticContributor {
         final usedDep = dependencies[missingDep];
         if (usedDep == null) return false;
 
-        return usedDep.references.any((ref) {
-          final element = ref.staticElement;
-          if (element != null && isPropVariable(element)) {
-            // foo()
-            if (ref.parent.tryCast<InvocationExpression>()?.function == ref) {
-              return true;
-            }
-            // foo.call()
-            final inv = PropertyInvocation.detectClosest(ref);
-            if (inv != null) {
-              return inv.target == ref && inv.functionName.name == 'call';
-            }
-          }
-
-          if (element != null && isProps(element)) {
-            final inv = PropertyInvocation.detectClosest(ref);
-            if (inv != null) {
-              final target = inv.target;
-              // props.foo()
-              if (target == ref) {
-                return true;
+        return usedDep.references.any((union) {
+          return union.switchCase(
+            (ref) {
+              final element = ref.staticElement;
+              if (element != null && isPropVariable(element)) {
+                // foo()
+                if (ref.parent.tryCast<InvocationExpression>()?.function == ref) {
+                  return true;
+                }
+                // foo.call()
+                final inv = PropertyInvocation.detectClosest(ref);
+                if (inv != null) {
+                  return inv.target == ref && inv.functionName.name == 'call';
+                }
               }
-              // props.foo.call()
-              if (inv.functionName.name == 'call' &&
-                  target != null &&
-                  getSimpleTargetAndPropertyName(target, allowMethodInvocation: false)?.item1 == ref) {
-                return true;
+
+              if (element != null && isProps(element)) {
+                final inv = PropertyInvocation.detectClosest(ref);
+                if (inv != null) {
+                  final target = inv.target;
+                  // props.foo()
+                  if (target == ref) {
+                    return true;
+                  }
+                  // props.foo.call()
+                  if (inv.functionName.name == 'call' &&
+                      target != null &&
+                      getSimpleTargetAndPropertyName(target, allowMethodInvocation: false)?.item1 == ref) {
+                    return true;
+                  }
+                }
               }
-            }
-          }
 
-          return false;
+              return false;
+            },
+            // This check isn't relevant for NamedType references.
+            (_) => false,
+          );
         });
       }).toList();
       if (missingCallbackDeps.isNotEmpty) {
@@ -1319,7 +1360,12 @@ class ExhaustiveDeps extends DiagnosticContributor {
           break;
         }
         final usedDep = dependencies[missingDep]!;
-        for (final reference in usedDep.references) {
+        for (final referenceUnion in usedDep.references) {
+          // Filter out NamedType (generic type parameters) since this check isn't relevant to them.
+          // Use a LHS type to ensure we're picking the correct type from the union.
+          // ignore: omit_local_variable_types
+          final Identifier? reference = referenceUnion.a;
+          if (reference == null) continue;
           // Try to see if we have setState(someExpr(missingDep)).
           for (var maybeCall = reference.parent;
               maybeCall != null && maybeCall != componentOrCustomHookFunction?.body;
@@ -1335,7 +1381,7 @@ class ExhaustiveDeps extends DiagnosticContributor {
                   // This case is necessary for `stateVar.set` calls, since key for setStateCallSites is the `stateVar` identifier, not `set`.
                   setStateCallSites.getNullableKey(maybeCall.tryCast<MethodInvocation>()?.target.tryCast());
               if (correspondingStateVariable != null) {
-                if ('${correspondingStateVariable.name.name}.value' == missingDep) {
+                if ('${correspondingStateVariable.name.lexeme}.value' == missingDep) {
                   // setCount(count + 1)
                   setStateRecommendation = _SetStateRecommendation(
                     missingDep: missingDep,
@@ -1516,7 +1562,7 @@ class ReactiveHookCallbackInfo {
 class _Dependency {
   final bool isStable;
 
-  final List<Identifier> references;
+  final List<Union<Identifier, NamedType>> references;
 
   bool isUsedSomewhereAsCascadeTarget = false;
 
@@ -1525,7 +1571,7 @@ class _Dependency {
   @override
   String toString() => prettyPrint({
         'isStable': isStable,
-        'references': references,
+        'references': references.map((r) => r.either).toList(),
         'isUsedSomewhereAsCascadeTarget': isUsedSomewhereAsCascadeTarget,
       });
 }
@@ -1544,8 +1590,25 @@ class _RefInEffectCleanup {
       });
 }
 
-Iterable<Identifier> resolvedReferencesWithin(AstNode node) =>
-    allDescendantsOfType<Identifier>(node).where((e) => e.staticElement != null);
+Iterable<Union<Identifier, NamedType>> resolvedReferencesWithin(AstNode node) sync* {
+  for (final descendant in allDescendants(node)) {
+    if (descendant is Identifier) {
+      if (descendant.staticElement != null) {
+        yield Union.a(descendant);
+      }
+    } else if (descendant is NamedType) {
+      if (descendant.element != null) {
+        yield Union.b(descendant);
+      }
+    }
+  }
+}
+
+extension on NamedType {
+  // NamedType.element is added in analyzer 5.11.0; we can't resolve to that version in Dart 2.18,
+  // so we'll add it here so we don't have to go back through and change it later.
+  Element? get element => name.staticElement;
+}
 
 enum HookTypeWithStableMethods { stateHook, reducerHook, transitionHook }
 
@@ -1658,7 +1721,7 @@ bool _hasDeclarationWithName(FunctionBody body, String childName) {
   // Use a visitor so we properly handle declarations inside blocks.
   var hasMatch = false;
   body.visitChildren(_ChildLocalVariableOrFunctionDeclarationVisitor((_, name) {
-    if (name.name == childName) {
+    if (name.lexeme == childName) {
       hasMatch = true;
     }
   }));
@@ -1666,7 +1729,7 @@ bool _hasDeclarationWithName(FunctionBody body, String childName) {
 }
 
 class _ChildLocalVariableOrFunctionDeclarationVisitor extends RecursiveAstVisitor<void> {
-  final void Function(Declaration, SimpleIdentifier name) onChildLocalDeclaration;
+  final void Function(Declaration, Token name) onChildLocalDeclaration;
 
   _ChildLocalVariableOrFunctionDeclarationVisitor(this.onChildLocalDeclaration);
 
@@ -1922,7 +1985,7 @@ _Recommendations collectRecommendations({
 String? getConstructionExpressionType(Expression node) {
   if (node is InstanceCreationExpression) {
     if (node.isConst) return null;
-    return node.constructorName.type2.name.name;
+    return node.constructorName.type.name.name;
   } else if (node is ListLiteral) {
     return _DepType.list;
   } else if (node is SetOrMapLiteral) {
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/missing_required_prop.dart b/tools/analyzer_plugin/lib/src/diagnostic/missing_required_prop.dart
index 8b9aa94e7..ba1a6841a 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/missing_required_prop.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/missing_required_prop.dart
@@ -104,7 +104,7 @@ class MissingRequiredPropDiagnostic extends ComponentUsageDiagnosticContributor
           }
 
           // ignore: unnecessary_parenthesis
-          final accessorClass = (_cachedAccessorClass ??= typeLibrary.getType('Accessor')!);
+          final accessorClass = (_cachedAccessorClass ??= typeLibrary.getClass('Accessor')!);
           if (!result.typeSystem.isAssignableTo(type, accessorClass.thisType)) {
             return false;
           }
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/non_defaulted_prop.dart b/tools/analyzer_plugin/lib/src/diagnostic/non_defaulted_prop.dart
index 0be2d94a7..892ef5a5d 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/non_defaulted_prop.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/non_defaulted_prop.dart
@@ -91,7 +91,7 @@ class NonDefaultedPropDiagnostic extends DiagnosticContributor {
       final access = tuple.item1;
       final variable = tuple.item2;
 
-      final variableName = variable.name.name;
+      final variableName = variable.name.lexeme;
 
       await collector.addErrorWithFix(
         code,
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/pseudo_static_lifecycle.dart b/tools/analyzer_plugin/lib/src/diagnostic/pseudo_static_lifecycle.dart
index 3c94d4b9c..ec42b4f0e 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/pseudo_static_lifecycle.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/pseudo_static_lifecycle.dart
@@ -73,7 +73,7 @@ class PseudoStaticLifecycleDiagnostic extends DiagnosticContributor {
       if (reference is SuperExpression || reference is ThisExpression) {
         final parent = reference.parent;
         if (parent is MethodInvocation) {
-          if (parent.methodName.name == enclosingMethodName.name) {
+          if (parent.methodName.name == enclosingMethodName.lexeme) {
             // Ignore super-calls to same method
             continue;
           } else {
@@ -82,7 +82,7 @@ class PseudoStaticLifecycleDiagnostic extends DiagnosticContributor {
             end = parent.methodName.end;
           }
         } else if (parent is PropertyAccess) {
-          if (parent.propertyName.name == enclosingMethodName.name) {
+          if (parent.propertyName.name == enclosingMethodName.lexeme) {
             // Ignore super-calls to same getter
             continue;
           } else {
@@ -99,7 +99,7 @@ class PseudoStaticLifecycleDiagnostic extends DiagnosticContributor {
       collector.addError(
         code,
         result.location(offset: offset, end: end),
-        errorMessageArgs: [enclosingMethodName.name],
+        errorMessageArgs: [enclosingMethodName.lexeme],
       );
     }
   }
@@ -115,17 +115,17 @@ class LifecycleMethodVisitor extends GeneralizingAstVisitor<void> {
 
   @override
   void visitMixinDeclaration(MixinDeclaration node) {
-    visitClassOrMixinDeclaration(node);
+    visitClassOrMixinDeclaration(node, node.members);
   }
 
   @override
   void visitClassDeclaration(ClassDeclaration node) {
-    visitClassOrMixinDeclaration(node);
+    visitClassOrMixinDeclaration(node, node.members);
   }
 
-  void visitClassOrMixinDeclaration(ClassOrMixinDeclaration node) {
-    for (final member in node.members) {
-      if (member is MethodDeclaration && staticMethodNames.contains(member.name.name)) {
+  void visitClassOrMixinDeclaration(NamedCompilationUnitMember node, List<ClassMember> members) {
+    for (final member in members) {
+      if (member is MethodDeclaration && staticMethodNames.contains(member.name.lexeme)) {
         final visitor = ReferenceVisitor();
         member.body.accept(visitor);
         nonStaticReferences.addAll(visitor.nonStaticReferences);
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/render_return_value.dart b/tools/analyzer_plugin/lib/src/diagnostic/render_return_value.dart
index 690753842..86c900c4e 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/render_return_value.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/render_return_value.dart
@@ -183,7 +183,7 @@ class ClassComponentRenderVisitor extends SimpleAstVisitor<void> {
 
   @override
   void visitMethodDeclaration(MethodDeclaration node) {
-    if (node.name.name == 'render') {
+    if (node.name.lexeme == 'render') {
       renderReturnExpressions.addAll(node.body.returnExpressions);
     }
   }
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/variadic_children_with_keys.dart b/tools/analyzer_plugin/lib/src/diagnostic/variadic_children_with_keys.dart
index ac4fbfd10..440158055 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/variadic_children_with_keys.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/variadic_children_with_keys.dart
@@ -73,7 +73,7 @@ class VariadicChildrenWithKeys extends ComponentUsageDiagnosticContributor {
   @override
   computeErrorsForUsage(result, collector, usage) async {
     String? reasonWhyUnnecessary;
-    final parentMethodName = usage.node.thisOrAncestorOfType<MethodDeclaration>()?.name.name;
+    final parentMethodName = usage.node.thisOrAncestorOfType<MethodDeclaration>()?.name.lexeme;
 
     final parent = usage.node.parent;
 
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/visitors/non_static_reference_visitor.dart b/tools/analyzer_plugin/lib/src/diagnostic/visitors/non_static_reference_visitor.dart
index fb2e028b8..b3bc4e564 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/visitors/non_static_reference_visitor.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/visitors/non_static_reference_visitor.dart
@@ -69,7 +69,7 @@ bool referencesImplicitThis(SimpleIdentifier identifier) {
   }
   // not a class member
   final Element? enclosingElement = element.enclosingElement;
-  if (enclosingElement is! ClassElement) {
+  if (enclosingElement is! InterfaceOrAugmentationElement) {
     return false;
   }
   // comment
diff --git a/tools/analyzer_plugin/lib/src/diagnostic/visitors/proptypes_visitors.dart b/tools/analyzer_plugin/lib/src/diagnostic/visitors/proptypes_visitors.dart
index 60c501817..58f1b76e4 100644
--- a/tools/analyzer_plugin/lib/src/diagnostic/visitors/proptypes_visitors.dart
+++ b/tools/analyzer_plugin/lib/src/diagnostic/visitors/proptypes_visitors.dart
@@ -20,7 +20,7 @@ class PropTypesVisitor extends SimpleAstVisitor<void> {
 
   @override
   void visitMethodDeclaration(MethodDeclaration node) {
-    if (node.name.name == 'propTypes') {
+    if (node.name.lexeme == 'propTypes') {
       node.body.accept(mapVisitor);
     }
   }
diff --git a/tools/analyzer_plugin/lib/src/plugin.dart b/tools/analyzer_plugin/lib/src/plugin.dart
index 33af9615e..f67d28b85 100644
--- a/tools/analyzer_plugin/lib/src/plugin.dart
+++ b/tools/analyzer_plugin/lib/src/plugin.dart
@@ -31,31 +31,24 @@
 
 import 'dart:async';
 
-import 'package:analyzer/dart/analysis/context_builder.dart';
-import 'package:analyzer/dart/analysis/context_locator.dart';
-import 'package:analyzer/dart/analysis/context_root.dart' as analyzer;
+import 'package:analyzer/dart/analysis/analysis_context.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/file_system/file_system.dart';
-// ignore: implementation_imports
-import 'package:analyzer/src/dart/analysis/context_builder.dart' show ContextBuilderImpl;
-// ignore: implementation_imports
-import 'package:analyzer/src/dart/analysis/driver.dart' show AnalysisDriver, AnalysisDriverGeneric;
-import 'package:analyzer_plugin/plugin/navigation_mixin.dart';
 import 'package:analyzer_plugin/plugin/plugin.dart';
 import 'package:analyzer_plugin/protocol/protocol_generated.dart' as plugin;
-import 'package:analyzer_plugin/utilities/navigation/navigation.dart';
-import 'package:over_react_analyzer_plugin/src/analysis_options/plugin_analysis_options.dart';
 import 'package:over_react_analyzer_plugin/src/analysis_options/reader.dart';
 import 'package:over_react_analyzer_plugin/src/assist/add_props.dart';
 import 'package:over_react_analyzer_plugin/src/assist/convert_class_or_function_component.dart';
 import 'package:over_react_analyzer_plugin/src/assist/extract_component.dart';
 import 'package:over_react_analyzer_plugin/src/assist/refs/add_create_ref_assist.dart';
+
 // Can't import this until it stops importing non-null-safe code, otherwise the plugin won't start.
 //import 'package:over_react_analyzer_plugin/src/assist/toggle_stateful.dart';
 import 'package:over_react_analyzer_plugin/src/async_plugin_apis/assist.dart';
 import 'package:over_react_analyzer_plugin/src/async_plugin_apis/diagnostic.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/arrow_function_prop.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/bad_key.dart';
+
 // Can't import this until it stops importing non-null-safe code, otherwise the plugin won't start.
 //import 'package:over_react_analyzer_plugin/src/diagnostic/boilerplate_validator.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/callback_ref.dart';
@@ -65,6 +58,7 @@ import 'package:over_react_analyzer_plugin/src/diagnostic/dom_prop_types.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/duplicate_prop_cascade.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/exhaustive_deps.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/forward_only_dom_props_to_dom_builders.dart';
+
 // Can't import this until it stops importing non-null-safe code, otherwise the plugin won't start.
 //import 'package:over_react_analyzer_plugin/src/diagnostic/incorrect_doc_comment_location.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/invalid_child.dart';
@@ -81,18 +75,14 @@ import 'package:over_react_analyzer_plugin/src/diagnostic/style_value_diagnostic
 import 'package:over_react_analyzer_plugin/src/diagnostic/variadic_children.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic/variadic_children_with_keys.dart';
 import 'package:over_react_analyzer_plugin/src/diagnostic_contributor.dart';
-import 'package:over_react_analyzer_plugin/src/util/util.dart';
 
-abstract class OverReactAnalyzerPluginBase extends ServerPlugin
-    with
+mixin OverReactAnalyzerPluginBase
+    on
+        ServerPlugin,
 //    OutlineMixin, DartOutlineMixin,
         DiagnosticMixin,
-        NavigationMixin,
-        DartNavigationMixin,
         AsyncAssistsMixin,
         AsyncDartAssistsMixin {
-  OverReactAnalyzerPluginBase(ResourceProvider provider) : super(provider);
-
   @override
   final pluginOptionsReader = PluginOptionsReader();
 
@@ -118,30 +108,10 @@ abstract class OverReactAnalyzerPluginBase extends ServerPlugin
       ];
 
   @override
-  List<NavigationContributor> getNavigationContributors(String path) => [];
-
-  // TODO(greg) is there a better way to do this?
-  analyzer.ContextRoot? _analyzerContextRootForPath(String path) {
-    final driver = driverForPath(path);
-    if (driver == null) return null;
-
-    // TODO should this throw?
-    if (driver is! AnalysisDriver) return null;
-
-    return driver.analysisContext?.contextRoot;
-  }
-
-  PluginAnalysisOptions? optionsForPath(String path) {
-    // Do not use protocol.ContextRoot's optionsFile, since it's null at least in tests.
-    // We'll use te driver's context instead.
-    final contextRoot = _analyzerContextRootForPath(path);
-    if (contextRoot == null) return null;
-    return pluginOptionsReader.getOptionsForContextRoot(contextRoot);
-  }
-
-  @override
-  List<DiagnosticContributor> getDiagnosticContributors(String path) {
-    final options = optionsForPath(path);
+  List<DiagnosticContributor> getDiagnosticContributors(AnalysisContext analysisContext, String path) {
+    // Do not use protocol.ContextRoot's optionsFile, since it's null at least in tests;
+    // get it from analysisContext instead.
+    final options = pluginOptionsReader.getOptionsForContextRoot(analysisContext.contextRoot);
     return [
       PropTypesReturnValueDiagnostic(),
       DuplicatePropCascadeDiagnostic(),
@@ -183,103 +153,34 @@ abstract class OverReactAnalyzerPluginBase extends ServerPlugin
   //       // Disabled for now since it doesn't seem to work consistently
   //       new ReactElementOutlineContributor(),
   //     ];
-}
-
-/// Analyzer plugin for over_react.
-class OverReactAnalyzerPlugin extends OverReactAnalyzerPluginBase {
-  OverReactAnalyzerPlugin(ResourceProvider provider) : super(provider);
 
   @override
-  String get name => 'over_react';
-
-  @override
-  String get contactInfo => 'Workiva Slack channel: #react-analyzer-plugin';
+  Future<void> analyzeFile({required AnalysisContext analysisContext, required String path}) async {
+    if (!path.endsWith('.dart')) return;
 
-  @override
-  AnalysisDriverGeneric createAnalysisDriver(plugin.ContextRoot contextRoot) {
-    final root = ContextLocator(resourceProvider: resourceProvider).locateRoots(
-      includedPaths: [contextRoot.root],
-      excludedPaths: contextRoot.exclude,
-      optionsFile: contextRoot.optionsFile,
-    ).single;
-    final contextBuilder = ContextBuilder(resourceProvider: resourceProvider) as ContextBuilderImpl;
-    final context = contextBuilder.createContext(
-      contextRoot: root,
-      scheduler: analysisDriverScheduler,
-      byteStore: byteStore,
-      performanceLog: performanceLog,
-    );
-    final driver = context.driver;
-    try {
-      driver.currentSession.analysisContext;
-    } catch (_) {
-      channel.sendNotification(
-          plugin.PluginErrorParams(false, 'Error fetching analysis context; assists may be unavailable', '')
-              .toNotification());
-    }
-    runZonedGuarded(() {
-      driver.results.whereType<ResolvedUnitResult>().listen(processDiagnosticsForResult);
+    await runZonedGuarded(() async {
+      final result = await analysisContext.currentSession.getResolvedUnit(path);
+      if (result is ResolvedUnitResult) {
+        await getAllErrors(result);
+      }
     }, (e, stackTrace) {
       channel.sendNotification(plugin.PluginErrorParams(false, e.toString(), stackTrace.toString()).toNotification());
     });
-    return driver;
   }
+}
 
-  @override
-  void contentChanged(String path) {
-    super.driverForPath(path)!.addFile(path);
-  }
+/// Analyzer plugin for over_react.
+class OverReactAnalyzerPlugin extends ServerPlugin
+    with
+        DiagnosticMixin,
+        AsyncAssistsMixin,
+        AsyncDartAssistsMixin,
+        OverReactAnalyzerPluginBase {
+  OverReactAnalyzerPlugin(ResourceProvider provider) : super(resourceProvider: provider);
 
   @override
-  Future<plugin.AnalysisSetContextRootsResult> handleAnalysisSetContextRoots(
-      plugin.AnalysisSetContextRootsParams parameters) async {
-    final result = await super.handleAnalysisSetContextRoots(parameters);
-    // The super-call adds files to the driver, so we need to prioritize them so they get analyzed.
-    _updatePriorityFiles();
-    return result;
-  }
-
-  List<String> _filesFromSetPriorityFilesRequest = [];
+  String get name => 'over_react';
 
   @override
-  Future<plugin.AnalysisSetPriorityFilesResult> handleAnalysisSetPriorityFiles(
-      plugin.AnalysisSetPriorityFilesParams parameters) async {
-    _filesFromSetPriorityFilesRequest = parameters.files;
-    _updatePriorityFiles();
-    return plugin.AnalysisSetPriorityFilesResult();
-  }
-
-  /// AnalysisDriver doesn't fully resolve files that are added via `addFile`; they need to be either explicitly requested
-  /// via `getResult`/etc, or added to `priorityFiles`.
-  ///
-  /// This method updates `priorityFiles` on the driver to include:
-  ///
-  /// - Any files prioritized by the analysis server via [handleAnalysisSetPriorityFiles]
-  /// - All other files the driver has been told to analyze via addFile (in [ServerPlugin.handleAnalysisSetContextRoots])
-  ///
-  /// As a result, [processDiagnosticsForResult] will get called with resolved units, and thus all of our diagnostics
-  /// will get run on all files in the repo instead of only the currently open/edited ones!
-  void _updatePriorityFiles() {
-    final filesToFullyResolve = {
-      // Ensure these go first, since they're actually considered priority; ...
-      ..._filesFromSetPriorityFilesRequest,
-
-      /// ... all other files need to be analyzed, but don't trump priority/
-      for (var driver2 in driverMap.values) ...(driver2 as AnalysisDriver).addedFiles,
-    };
-
-    // From ServerPlugin.handleAnalysisSetPriorityFiles
-    final filesByDriver = <AnalysisDriverGeneric, List<String>>{};
-    for (final file in filesToFullyResolve) {
-      var contextRoot = contextRootContaining(file);
-      if (contextRoot != null) {
-        // TODO(brianwilkerson) Which driver should we use if there is no context root?
-        var driver = driverMap[contextRoot]!;
-        filesByDriver.putIfAbsent(driver, () => <String>[]).add(file);
-      }
-    }
-    filesByDriver.forEach((driver, files) {
-      driver.priorityFiles = files;
-    });
-  }
+  String get contactInfo => 'Workiva Slack channel: #react-analyzer-plugin';
 }
diff --git a/tools/analyzer_plugin/lib/src/util/analyzer_util.dart b/tools/analyzer_plugin/lib/src/util/analyzer_util.dart
index a3157f7ff..4afc5cb28 100644
--- a/tools/analyzer_plugin/lib/src/util/analyzer_util.dart
+++ b/tools/analyzer_plugin/lib/src/util/analyzer_util.dart
@@ -1,5 +1,5 @@
-// From analyzer 1.7.2 src/dart/ast/utilities.dart
-// Permalink: https://github.com/dart-lang/sdk/blob/d97bd979570c4aacde322d8b04256ce477aa9729/pkg/analyzer/lib/src/dart/ast/utilities.dart
+// Adapted from analyzer 5.13.0 src/dart/ast/utilities.dart
+// Permalink: https://github.com/dart-lang/sdk/blob/efe0ca193f1c1485efc5467fb8dc9dfca6085d39/pkg/analyzer/lib/src/dart/ast/utilities.dart#L1687
 //
 // Copyright 2013, the Dart project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
@@ -29,13 +29,16 @@
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 import 'package:analyzer/dart/ast/ast.dart';
-import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 
 /// An object used to locate the [AstNode] associated with a source range, given
 /// the AST structure built from the source. More specifically, they will return
 /// the [AstNode] with the shortest length whose source range completely
-/// encompasses the specified range.
+/// encompasses the specified range with some exceptions:
+///
+/// - Offsets that fall between the name and type/formal parameter list of a
+///   declaration will return the declaration node and not the parameter list
+///   node.
 class NodeLocator extends UnifyingAstVisitor<void> {
   /// The start offset of the range used to identify the node.
   final int _startOffset;
@@ -70,9 +73,47 @@ class NodeLocator extends UnifyingAstVisitor<void> {
     } catch (_) {
       return null;
     }
+
     return _foundNode;
   }
 
+  @override
+  void visitConstructorDeclaration(ConstructorDeclaration node) {
+    // Names do not have AstNodes but offsets at the end should be treated as
+    // part of the declaration (not parameter list).
+    if (_startOffset == _endOffset &&
+        _startOffset == (node.name ?? node.returnType).end) {
+      _foundNode = node;
+      return;
+    }
+
+    super.visitConstructorDeclaration(node);
+  }
+
+  @override
+  void visitFunctionDeclaration(FunctionDeclaration node) {
+    // Names do not have AstNodes but offsets at the end should be treated as
+    // part of the declaration (not parameter list).
+    if (_startOffset == _endOffset && _startOffset == node.name.end) {
+      _foundNode = node;
+      return;
+    }
+
+    super.visitFunctionDeclaration(node);
+  }
+
+  @override
+  void visitMethodDeclaration(MethodDeclaration node) {
+    // Names do not have AstNodes but offsets at the end should be treated as
+    // part of the declaration (not parameter list).
+    if (_startOffset == _endOffset && _startOffset == node.name.end) {
+      _foundNode = node;
+      return;
+    }
+
+    super.visitMethodDeclaration(node);
+  }
+
   @override
   void visitNode(AstNode node) {
     // Don't visit a new tree if the result has been already found.
@@ -87,7 +128,7 @@ class NodeLocator extends UnifyingAstVisitor<void> {
       // Fasta scanner reports unterminated string literal errors
       // and generates a synthetic string token with non-zero length.
       // Because of this, check for length > 0 rather than !isSynthetic.
-      if (endToken.type == TokenType.EOF || endToken.length > 0) {
+      if (endToken.isEof || endToken.length > 0) {
         break;
       }
       endToken = endToken.previous!;
@@ -117,7 +158,11 @@ class NodeLocator extends UnifyingAstVisitor<void> {
 
 /// An object used to locate the [AstNode] associated with a source range.
 /// More specifically, they will return the deepest [AstNode] which completely
-/// encompasses the specified range.
+/// encompasses the specified range with some exceptions:
+///
+/// - Offsets that fall between the name and type/formal parameter list of a
+///   declaration will return the declaration node and not the parameter list
+///   node.
 class NodeLocator2 extends UnifyingAstVisitor<void> {
   /// The inclusive start offset of the range used to identify the node.
   final int _startOffset;
@@ -151,6 +196,43 @@ class NodeLocator2 extends UnifyingAstVisitor<void> {
     return _foundNode;
   }
 
+  @override
+  void visitConstructorDeclaration(ConstructorDeclaration node) {
+    // Names do not have AstNodes but offsets at the end should be treated as
+    // part of the declaration (not parameter list).
+    if (_startOffset == _endOffset &&
+        _startOffset == (node.name ?? node.returnType).end) {
+      _foundNode = node;
+      return;
+    }
+
+    super.visitConstructorDeclaration(node);
+  }
+
+  @override
+  void visitFunctionDeclaration(FunctionDeclaration node) {
+    // Names do not have AstNodes but offsets at the end should be treated as
+    // part of the declaration (not parameter list).
+    if (_startOffset == _endOffset && _startOffset == node.name.end) {
+      _foundNode = node;
+      return;
+    }
+
+    super.visitFunctionDeclaration(node);
+  }
+
+  @override
+  void visitMethodDeclaration(MethodDeclaration node) {
+    // Names do not have AstNodes but offsets at the end should be treated as
+    // part of the declaration (not parameter list).
+    if (_startOffset == _endOffset && _startOffset == node.name.end) {
+      _foundNode = node;
+      return;
+    }
+
+    super.visitMethodDeclaration(node);
+  }
+
   @override
   void visitNode(AstNode node) {
     // Don't visit a new tree if the result has been already found.
@@ -165,7 +247,7 @@ class NodeLocator2 extends UnifyingAstVisitor<void> {
       // Fasta scanner reports unterminated string literal errors
       // and generates a synthetic string token with non-zero length.
       // Because of this, check for length > 0 rather than !isSynthetic.
-      if (endToken.type == TokenType.EOF || endToken.length > 0) {
+      if (endToken.isEof || endToken.length > 0) {
         break;
       }
       endToken = endToken.previous!;
diff --git a/tools/analyzer_plugin/lib/src/util/ast_util.dart b/tools/analyzer_plugin/lib/src/util/ast_util.dart
index eea0ad18c..b8803f405 100644
--- a/tools/analyzer_plugin/lib/src/util/ast_util.dart
+++ b/tools/analyzer_plugin/lib/src/util/ast_util.dart
@@ -17,8 +17,8 @@ import 'util.dart';
 /// or null if the [element] doesn't correspond to a variable declaration, or if it can't be found in [root].
 VariableDeclaration? lookUpVariable(Element element, AstNode root) {
   final node = NodeLocator2(element.nameOffset).searchWithin(root);
-  if (node is Identifier && node.staticElement == element) {
-    return node.parent.tryCast<VariableDeclaration>();
+  if (node is VariableDeclaration && node.declaredElement == element) {
+    return node;
   }
 
   return null;
@@ -31,10 +31,11 @@ VariableDeclaration? lookUpVariable(Element element, AstNode root) {
 /// Returns null if the [element] doesn't correspond to one of these cases, or if it can't be found in [root].
 FunctionExpression? lookUpFunction(Element element, AstNode root) {
   final node = NodeLocator2(element.nameOffset).searchWithin(root);
-  if (node is Identifier && node.staticElement == element) {
-    final parent = node.parent;
-    return parent.tryCast<FunctionDeclaration>()?.functionExpression ??
-        parent.tryCast<VariableDeclaration>()?.initializer?.tryCast<FunctionExpression>();
+  if (node is FunctionDeclaration && node.declaredElement == element) {
+    return node.functionExpression;
+  }
+  if (node is VariableDeclaration && node.declaredElement == element) {
+    return node.initializer?.tryCast<FunctionExpression>();
   }
 
   return null;
@@ -132,11 +133,6 @@ extension TypeOrBound on DartType {
   }
 }
 
-extension ClassOrMixinDeclarationUtils on ClassOrMixinDeclaration {
-  /// Similar to [getField], but returns the entire declaration instead.
-  FieldDeclaration? getFieldDeclaration(String name) => getField(name)?.thisOrAncestorOfType<FieldDeclaration>();
-}
-
 int prevLine(int offset, LineInfo lineInfo) {
   return lineInfo.getOffsetOfLine(lineInfo.getLocation(offset).lineNumber - 1);
 }
@@ -333,7 +329,7 @@ extension FunctionBodyUtils on FunctionBody {
   MethodDeclaration? get parentMethod => parent?.tryCast();
 
   String get functionNameOrDescription {
-    final name = parentExpression?.parentDeclaration?.name.name;
+    final name = parentExpression?.parentDeclaration?.name.lexeme;
     if (name != null) return name;
 
     // TODO come up with a better description in some cases
diff --git a/tools/analyzer_plugin/lib/src/util/function_components.dart b/tools/analyzer_plugin/lib/src/util/function_components.dart
index 9fbf400e9..ed14ad3d7 100644
--- a/tools/analyzer_plugin/lib/src/util/function_components.dart
+++ b/tools/analyzer_plugin/lib/src/util/function_components.dart
@@ -1,4 +1,5 @@
 import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/ast/visitor.dart';
 import 'package:over_react_analyzer_plugin/src/util/hooks.dart';
 
@@ -46,7 +47,7 @@ class FunctionComponent {
   /// The name of this function component's factory, if it exists and could be found.
   ///
   /// See [factoryVariable] for more info on when this may be null.
-  SimpleIdentifier? get factoryName => factoryVariable?.name;
+  Token? get factoryName => factoryVariable?.name;
 }
 
 FunctionComponent? getClosestFunctionComponent(AstNode node) {
diff --git a/tools/analyzer_plugin/lib/src/util/hooks.dart b/tools/analyzer_plugin/lib/src/util/hooks.dart
index 2ef2a4b8d..6f6824455 100644
--- a/tools/analyzer_plugin/lib/src/util/hooks.dart
+++ b/tools/analyzer_plugin/lib/src/util/hooks.dart
@@ -16,7 +16,7 @@ FunctionBody? getClosestCustomHookFunction(AstNode node) =>
 
 bool isCustomHookFunction(FunctionBody body) {
   final declaration = body.parentDeclaration;
-  return declaration != null && isHookName(declaration.name.name);
+  return declaration != null && isHookName(declaration.name.lexeme);
 }
 
 /// A utility class that provides information about a usage of a React hook.
diff --git a/tools/analyzer_plugin/lib/src/util/ignore_info.dart b/tools/analyzer_plugin/lib/src/util/ignore_info.dart
index 3ce756a5b..5b1b3c04b 100644
--- a/tools/analyzer_plugin/lib/src/util/ignore_info.dart
+++ b/tools/analyzer_plugin/lib/src/util/ignore_info.dart
@@ -29,7 +29,8 @@
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
-import 'package:analyzer/src/dart/ast/token.dart'; // ignore: implementation_imports
+// ignore: implementation_imports
+import 'package:analyzer/src/dart/ast/token.dart' show CommentToken;
 
 /// The name and location of a diagnostic name in an ignore comment.
 class DiagnosticName implements IgnoredElement {
@@ -103,13 +104,12 @@ class IgnoreInfo {
   /// Initialize a newly created instance of this class to represent the ignore
   /// comments in the given compilation [unit].
   IgnoreInfo.forDart(CompilationUnit unit, String content) {
-    var lineInfo = unit.lineInfo!;
     for (final comment in unit.ignoreComments) {
       var lexeme = comment.lexeme;
       if (lexeme.contains('ignore:')) {
-        var location = lineInfo.getLocation(comment.offset);
+        var location = unit.lineInfo.getLocation(comment.offset);
         var lineNumber = location.lineNumber;
-        var offsetOfLine = lineInfo.getOffsetOfLine(lineNumber - 1);
+        var offsetOfLine = unit.lineInfo.getOffsetOfLine(lineNumber - 1);
         var beforeMatch = content.substring(
             offsetOfLine, offsetOfLine + location.columnNumber - 1);
         if (beforeMatch.trim().isEmpty) {
diff --git a/tools/analyzer_plugin/lib/src/util/react_types.dart b/tools/analyzer_plugin/lib/src/util/react_types.dart
index 83ea12981..0cc46b3c5 100644
--- a/tools/analyzer_plugin/lib/src/util/react_types.dart
+++ b/tools/analyzer_plugin/lib/src/util/react_types.dart
@@ -23,7 +23,7 @@ extension ReactTypes$Element on Element {
 
   bool isOrIsSubtypeOfElementFromPackage(String typeName, String packageName) {
     final element = this;
-    return element is ClassElement &&
+    return element is InterfaceElement &&
         (element.isElementFromPackage(typeName, packageName) ||
             element.allSupertypes.any((type) => type.element.isElementFromPackage(typeName, packageName)));
   }
diff --git a/tools/analyzer_plugin/lib/src/util/util.dart b/tools/analyzer_plugin/lib/src/util/util.dart
index 270c64a15..68e3ebacd 100644
--- a/tools/analyzer_plugin/lib/src/util/util.dart
+++ b/tools/analyzer_plugin/lib/src/util/util.dart
@@ -50,3 +50,32 @@ class Tuple2<T1, T2> {
 
   Tuple2(this.item1, this.item2);
 }
+
+/// A wrapper around two classes that can be used to pass data when the possible
+/// type is not limited to a single class.
+///
+/// Subset of package:union functionality
+class Union<A extends Object, B extends Object> {
+  final A? a;
+  final B? b;
+
+  Union.a(A this.a)
+      : b = null;
+  Union.b(B this.b)
+      : a = null;
+
+  /// Executes a callback based upon which field is set.
+  T switchCase<T>(T Function(A) onA, T Function(B) onB) {
+    final a = this.a;
+    return a != null ? onA(a) : onB(b!);
+  }
+}
+
+/// Utilities that supplement that functionality of the [Union] class.
+///
+/// C resolves statically to the closest common ancestor type of A and B.
+extension UnionHelper<C extends Object> on Union<C, C> {
+  /// Access [a] or [b] while allowing the analyzer to provide type inference
+  /// when possible.
+  C get either => (a ?? b)!;
+}
diff --git a/tools/analyzer_plugin/playground/pubspec.yaml b/tools/analyzer_plugin/playground/pubspec.yaml
index 4e5ba39f9..e1727b418 100644
--- a/tools/analyzer_plugin/playground/pubspec.yaml
+++ b/tools/analyzer_plugin/playground/pubspec.yaml
@@ -5,8 +5,8 @@ environment:
 dependencies:
   over_react: ^3.5.3
 dev_dependencies:
-  build_runner: '>=1.0.0 <3.0.0'
-  build_web_compilers: '>=2.0.0 <4.0.0'
+  build_runner: ^2.0.0
+  build_web_compilers: ^3.0.0
   workiva_analysis_options: ^1.1.0
 
 dependency_overrides:
diff --git a/tools/analyzer_plugin/pubspec.yaml b/tools/analyzer_plugin/pubspec.yaml
index 8f51ff5aa..86618599e 100644
--- a/tools/analyzer_plugin/pubspec.yaml
+++ b/tools/analyzer_plugin/pubspec.yaml
@@ -6,9 +6,8 @@ repository: https://github.com/Workiva/over_react/tree/master/tools/analyzer_plu
 environment:
   sdk: '>=2.12.0 <3.0.0'
 dependencies:
-  analyzer: ^2.4.0
-  # Can't be 0.7.0 since its results in errors around JenkinsSmiHash not existing
-  analyzer_plugin: ^0.8.0
+  analyzer: ^5.1.0
+  analyzer_plugin: ^0.11.0
   collection: ^1.15.0-nullsafety.4
   meta: ^1.6.0
   # Upon release, this should be pinned to the over_react version from ../../pubspec.yaml
@@ -23,17 +22,16 @@ dev_dependencies:
   build_test: ^2.0.0
   convert: ^3.0.0
   crypto: ^3.0.0
-  dart_dev: '>=3.8.5 <5.0.0'
+  dart_dev: ^4.0.0
   dart_style: ^2.0.0
   dependency_validator: ^3.0.0
   glob: ^2.0.0
   io: ^1.0.0
   logging: ^1.0.1
   markdown: ^4.0.0
-  package_config: ^2.0.0
-  pub_semver: ^2.0.0
   test: ^1.14.0
   test_reflective_loader: ^0.2.0
+  uuid: '>3.0.0 <5.0.0'
   workiva_analysis_options: ^1.1.0
 
 dependency_validator:
diff --git a/tools/analyzer_plugin/test/integration/assists/add_create_ref_test.dart b/tools/analyzer_plugin/test/integration/assists/add_create_ref_test.dart
index 24d80cacd..410c98646 100644
--- a/tools/analyzer_plugin/test/integration/assists/add_create_ref_test.dart
+++ b/tools/analyzer_plugin/test/integration/assists/add_create_ref_test.dart
@@ -57,13 +57,13 @@ final HasNoRefs = uiFunction<UiProps>(
 ''';
 
   Future<void> test_noAssist() async {
-    final source = newSource('test.dart', 'var foo = true;');
+    final source = newSource('var foo = true;');
     final selection = createSelection(source, '#var foo = true;#');
     await expectNoAssist(selection);
   }
 
   Future<void> test_noAssistWithExistingRefInFnComponentDecl() async {
-    final source = newSource('test.dart', '''
+    final source = newSource('''
 import 'package:over_react/over_react.dart';
 
 final HasRefs = uiFunction<UiProps>(
@@ -79,13 +79,13 @@ final HasRefs = uiFunction<UiProps>(
   }
 
   Future<void> test_noAssistWithSelectionOutsideReturnExpressionInFnComponent() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponent(fixed: false));
+    var source = newSource(usageSourceWithinFnComponent(fixed: false));
     var selection = createSelection(source, '<UiProps>(##');
     await expectNoAssist(selection);
   }
 
   Future<void> test_noAssistWithExistingRefInClassComponentDecl() async {
-    final source = newSource('test.dart', '''
+    final source = newSource('''
 import 'package:over_react/over_react.dart';
 
 part 'test.over_react.g.dart';
@@ -108,13 +108,13 @@ class HasRefsComponent extends UiComponent2<HasRefsProps> {
   }
 
   Future<void> test_noAssistWithSelectionOutsideReturnExpressionInClassComponent() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponent(fixed: false));
+    var source = newSource(usageSourceWithinClassComponent(fixed: false));
     var selection = createSelection(source, '<HasNoRefsProps> {##');
     await expectNoAssist(selection);
   }
 
   Future<void> test_classComponentAssist_componentNameSelection() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponent(fixed: false));
+    var source = newSource(usageSourceWithinClassComponent(fixed: false));
     var selection = createSelection(source, 'return (#Child#()');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
@@ -122,7 +122,7 @@ class HasRefsComponent extends UiComponent2<HasRefsProps> {
   }
 
   Future<void> test_classComponentAssist_zeroWidthSelection() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponent(fixed: false));
+    var source = newSource(usageSourceWithinClassComponent(fixed: false));
     var selection = createSelection(source, 'return (##Child()');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
@@ -130,7 +130,7 @@ class HasRefsComponent extends UiComponent2<HasRefsProps> {
   }
 
   Future<void> test_classComponentAssist_propCascadeSelection() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponent(fixed: false));
+    var source = newSource(usageSourceWithinClassComponent(fixed: false));
     var selection = createSelection(source, '..id ##= \'foo\'');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
@@ -138,7 +138,7 @@ class HasRefsComponent extends UiComponent2<HasRefsProps> {
   }
 
   Future<void> test_fnComponentAssist_componentNameSelection() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponent(fixed: false));
+    var source = newSource(usageSourceWithinFnComponent(fixed: false));
     var selection = createSelection(source, 'return (#Child#()');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
@@ -146,7 +146,7 @@ class HasRefsComponent extends UiComponent2<HasRefsProps> {
   }
 
   Future<void> test_fnComponentAssist_zeroWidthSelection() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponent(fixed: false));
+    var source = newSource(usageSourceWithinFnComponent(fixed: false));
     var selection = createSelection(source, 'return (##Child()');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
@@ -154,7 +154,7 @@ class HasRefsComponent extends UiComponent2<HasRefsProps> {
   }
 
   Future<void> test_fnComponentAssist_propCascadeSelection() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponent(fixed: false));
+    var source = newSource(usageSourceWithinFnComponent(fixed: false));
     var selection = createSelection(source, '..id ##= \'foo\'');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
diff --git a/tools/analyzer_plugin/test/integration/assists/add_props_test.dart b/tools/analyzer_plugin/test/integration/assists/add_props_test.dart
index c049e9118..364afe4b5 100644
--- a/tools/analyzer_plugin/test/integration/assists/add_props_test.dart
+++ b/tools/analyzer_plugin/test/integration/assists/add_props_test.dart
@@ -27,13 +27,13 @@ var foo = Dom.div()('hello');
 ''';
 
   Future<void> test_noAssist() async {
-    final source = newSource('test.dart', 'var foo = true;');
+    final source = newSource('var foo = true;');
     final selection = createSelection(source, '#var foo = true;#');
     await expectNoAssist(selection);
   }
 
   Future<void> test_noAssistForSelection() async {
-    final source = newSource('test.dart', simpleSource);
+    final source = newSource(simpleSource);
     final selection = createSelection(source, '#var foo#');
     await expectNoAssist(selection);
   }
@@ -48,7 +48,7 @@ var foo = Dom.div()('hello');
       ]);
 
   Future<void> test_addsParensAndPropsCascade() async {
-    var source = newSource('test.dart', simpleSource);
+    var source = newSource(simpleSource);
     var selection = createSelection(source, '#Dom.div#');
     final change = await expectAndGetSingleAssist(selection);
     source = applySourceChange(change, source);
@@ -62,7 +62,7 @@ var foo = (Dom.div()..)('hello');
   }
 
   Future<void> test_alreadyHasParens() async {
-    var source = newSource('test.dart', '''
+    var source = newSource('''
 import 'package:over_react/over_react.dart';
 var foo = (Dom.div())('hello');
 ''');
diff --git a/tools/analyzer_plugin/test/integration/assists/toggle_statefulness_test.dart b/tools/analyzer_plugin/test/integration/assists/toggle_statefulness_test.dart
index 99e9e2e4a..99364d6ab 100644
--- a/tools/analyzer_plugin/test/integration/assists/toggle_statefulness_test.dart
+++ b/tools/analyzer_plugin/test/integration/assists/toggle_statefulness_test.dart
@@ -27,7 +27,7 @@ class AddStatefulnessAssist extends AssistTestBase with BoilerplateAssistTestStr
   AssistKind get assistKindUnderTest => ToggleComponentStatefulness.makeStateful;
 
   Future<void> test_noAssist() async {
-    final source = newSource('test.dart', 'var foo = true;');
+    final source = newSource('var foo = true;');
     final selection = createSelection(source, '#var foo = true;#');
     await expectNoAssist(selection);
   }
@@ -35,7 +35,7 @@ class AddStatefulnessAssist extends AssistTestBase with BoilerplateAssistTestStr
   Future<void> test_noAssistOnFactory() async {
     final generatedSource = simpleUiComponentSource();
 
-    var source = newSource(fileName, generatedSource);
+    var source = newSource(generatedSource, path: fileName);
     var selection = createSelection(source, r'UiFactory<FooProps> #Foo# = _$Foo;');
     await expectNoAssist(selection);
   }
@@ -43,7 +43,7 @@ class AddStatefulnessAssist extends AssistTestBase with BoilerplateAssistTestStr
   Future<void> test_noAssistOnProps() async {
     final generatedSource = simpleUiComponentSource();
 
-    var source = newSource(fileName, generatedSource);
+    var source = newSource(generatedSource, path: fileName);
     var selection = createSelection(source, 'mixin #FooProps# on UiProps {}');
     await expectNoAssist(selection);
   }
@@ -66,7 +66,7 @@ class TestComponent extends UiComponent<TestProps> {
 }
 ''';
 
-    var source = newSource(fileName, oldBoilerplate);
+    var source = newSource(oldBoilerplate, path: fileName);
     var selection = createSelection(source, 'class #TestComponent# extends');
     await expectNoAssist(selection);
   }
@@ -86,13 +86,13 @@ class TestComponent extends AbstractBazComponent<TestProps> {
 }
 ''';
 
-    var source = newSource(fileName, unknownBase);
+    var source = newSource(unknownBase, path: fileName);
     var selection = createSelection(source, 'class #TestComponent# extends');
     await expectNoAssist(selection);
   }
 
   Future<void> test_addsStatefulness() async {
-    var retrievedSource = newSource(fileName, simpleUiComponentSource());
+    var retrievedSource = newSource(simpleUiComponentSource(), path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
@@ -100,7 +100,7 @@ class TestComponent extends AbstractBazComponent<TestProps> {
   }
 
   Future<void> test_addsStatefulnessWithoutDefaultProps() async {
-    var retrievedSource = newSource(fileName, simpleUiComponentSource(includeDefaultProps: false));
+    var retrievedSource = newSource(simpleUiComponentSource(includeDefaultProps: false), path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
@@ -108,7 +108,7 @@ class TestComponent extends AbstractBazComponent<TestProps> {
   }
 
   Future<void> test_addsStatefulnessToFlux() async {
-    var retrievedSource = newSource(fileName, fluxUiComponentSource());
+    var retrievedSource = newSource(fluxUiComponentSource(), path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
@@ -116,7 +116,7 @@ class TestComponent extends AbstractBazComponent<TestProps> {
   }
 
   Future<void> test_addsStatefulnessToFluxWithoutDefaultProps() async {
-    var retrievedSource = newSource(fileName, fluxUiComponentSource(includeDefaultProps: false));
+    var retrievedSource = newSource(fluxUiComponentSource(includeDefaultProps: false), path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
@@ -132,7 +132,7 @@ class RemoveStatefulnessAssist extends AssistTestBase with BoilerplateAssistTest
   AssistKind get assistKindUnderTest => ToggleComponentStatefulness.makeStateless;
 
   Future<void> test_noAssist() async {
-    final source = newSource('test.dart', 'var foo = true;');
+    final source = newSource('var foo = true;');
     final selection = createSelection(source, '#var foo = true;#');
     await expectNoAssist(selection);
   }
@@ -140,7 +140,7 @@ class RemoveStatefulnessAssist extends AssistTestBase with BoilerplateAssistTest
   Future<void> test_noAssistOnFactory() async {
     final generatedSource = simpleUiComponentSource(isStateful: true);
 
-    var source = newSource(fileName, generatedSource);
+    var source = newSource(generatedSource, path: fileName);
     var selection = createSelection(source, r'UiFactory<FooProps> #Foo# = _$Foo;');
     await expectNoAssist(selection);
   }
@@ -148,7 +148,7 @@ class RemoveStatefulnessAssist extends AssistTestBase with BoilerplateAssistTest
   Future<void> test_noAssistOnProps() async {
     final generatedSource = simpleUiComponentSource(isStateful: true);
 
-    var source = newSource(fileName, generatedSource);
+    var source = newSource(generatedSource, path: fileName);
     var selection = createSelection(source, 'mixin #FooProps# on UiProps {}');
     await expectNoAssist(selection);
   }
@@ -174,13 +174,13 @@ class TestComponent extends UiStatefulComponent<TestProps, TestState> {
 }
 ''';
 
-    var source = newSource(fileName, oldBoilerplate);
+    var source = newSource(oldBoilerplate, path: fileName);
     var selection = createSelection(source, 'class #TestComponent# extends');
     await expectNoAssist(selection);
   }
 
   Future<void> test_removesStatefulness() async {
-    var retrievedSource = newSource(fileName, simpleUiComponentSource(isStateful: true));
+    var retrievedSource = newSource(simpleUiComponentSource(isStateful: true), path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
@@ -208,7 +208,7 @@ class FooComponent extends UiStatefulComponent2<FooProps, FooState> {
 }
 ''';
 
-    var retrievedSource = newSource(fileName, statefulComponentWithNoInitialState);
+    var retrievedSource = newSource(statefulComponentWithNoInitialState, path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
@@ -216,7 +216,7 @@ class FooComponent extends UiStatefulComponent2<FooProps, FooState> {
   }
 
   Future<void> test_removesStatefulnessToFlux() async {
-    var retrievedSource = newSource(fileName, fluxUiComponentSource(isStateful: true));
+    var retrievedSource = newSource(fluxUiComponentSource(isStateful: true), path: fileName);
     var selection = createSelection(retrievedSource, componentNameSelector);
     final change = await expectAndGetSingleAssist(selection);
     retrievedSource = applySourceChange(change, retrievedSource);
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/analysis_options_configuration_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/analysis_options_configuration_test.dart
index ed1fff9c3..33a2223cf 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/analysis_options_configuration_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/analysis_options_configuration_test.dart
@@ -21,7 +21,7 @@ void main() {
     }
 
     Future<List<AnalysisError>> computeErrors({String sourceCode = rulesOfHooksErrorSourceCode}) async {
-      final source = testBase.newSource('test.dart', sourceCode);
+      final source = testBase.newSource(sourceCode);
 
       final result = await testBase.testPlugin.getResolvedUnitResult(testBase.sourcePath(source));
       final errors = await testBase.testPlugin.getAllErrors(result);
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/arrow_function_prop_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/arrow_function_prop_test.dart
index c1d07b792..99a9efa5b 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/arrow_function_prop_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/arrow_function_prop_test.dart
@@ -32,12 +32,12 @@ var foo = (Dom.div()
 ''';
 
   Future<void> test_noError() async {
-    final source = newSource('test.dart', 'var foo = true;');
+    final source = newSource('var foo = true;');
     expect(await getAllErrors(source), isEmpty);
   }
 
   Future<void> test_noErrorLastInCascade() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
       import 'package:over_react/over_react.dart';
       
       var foo = (Dom.div()
@@ -48,7 +48,7 @@ var foo = (Dom.div()
   }
 
   Future<void> test_noErrorLastInCascadeWithDescendantCascade() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
       import 'package:over_react/over_react.dart';
 
       part 'test.over_react.g.dart';
@@ -70,7 +70,7 @@ var foo = (Dom.div()
   }
 
   Future<void> test_noErrorForSelection() async {
-    final source = newSource('test.dart', simpleSource);
+    final source = newSource(simpleSource);
     final selection = createSelection(source, '#var foo#');
     await expectNoErrorFix(selection);
   }
@@ -85,7 +85,7 @@ var foo = (Dom.div()
       ]);
 
   Future<void> test_errorFix() async {
-    var source = newSource('test.dart', simpleSource);
+    var source = newSource(simpleSource);
     final selection = createSelection(source, "#(_) => 'click'#");
     final errorFix = await expectSingleErrorFix(selection);
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -100,7 +100,7 @@ var foo = (Dom.div()
   }
 
   Future<void> test_multipleErrors() async {
-    final source = newSource('test.dart', '''
+    final source = newSource('''
 import 'package:over_react/over_react.dart';
 var foo = (Dom.div()..onClick = (_) => null..key = 'foo')('');
 var bar = (Dom.div()..onSubmit = (_) => null..key = 'bar')('');
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/bad_key_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/bad_key_test.dart
index 2cbacbd8f..d5c2974ea 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/bad_key_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/bad_key_test.dart
@@ -23,7 +23,7 @@ abstract class BadKeyDiagnosticTest extends DiagnosticTestBase {
   @override
   get fixKindUnderTest => null;
 
-  Source newSourceWithPrefix(String sourceFragment) => newSource('test.dart', sourcePrefix + sourceFragment);
+  Source newSourceWithPrefix(String sourceFragment) => newSource(sourcePrefix + sourceFragment);
 
   static const sourcePrefix = /*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
@@ -47,6 +47,8 @@ class MyModelWithCustomToString {
   @override
   toString() => '$id';
 }
+
+enum AnEnum { foo }
 ''';
 }
 
@@ -59,6 +61,7 @@ class BadKeyDiagnosticTest_NoErrors extends BadKeyDiagnosticTest {
     final source = newSourceWithPrefix(/*language=dart*/ r'''
       test() => [
         (Dom.div()..key = 'a string')(),
+        (Dom.div()..key = AnEnum.foo)(),
         (Dom.div()..key = 122)(),
         (Dom.div()..key = modelVar.id)(),
         (Dom.div()..key = modelVarWithCustomToString)(),
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/boilerplate_validator_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/boilerplate_validator_test.dart
index 278e4ea2c..4de371e3c 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/boilerplate_validator_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/boilerplate_validator_test.dart
@@ -39,7 +39,7 @@ abstract class LegacyAbstractComponent<T extends UiProps> extends UiComponent<T>
 ''';
 
   Future<void> test_noErrors() async {
-    final _source = newSource('test.dart', source);
+    final _source = newSource(source);
     expect(await getAllErrors(_source), isEmpty);
   }
 }
@@ -59,7 +59,7 @@ ${BoilerplateValidatorDiagnosticTest.boilerplateThatRequiresGeneratedPart}
 ''';
 
   Future<void> test_error() async {
-    final _source = newSource('test.dart', source);
+    final _source = newSource(source);
     final allErrors = await getAllErrors(_source);
     expect(
       allErrors,
@@ -71,7 +71,7 @@ ${BoilerplateValidatorDiagnosticTest.boilerplateThatRequiresGeneratedPart}
   }
 
   Future<void> test_errorFix() async {
-    var _source = newSource('test.dart', source);
+    var _source = newSource(source);
     final selection = createSelection(_source, "UiFactory<FooProps> #Foo# =");
     final errorFix = await expectSingleErrorFix(selection);
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -101,7 +101,7 @@ part 'test.over_react.g.dart';
 ''';
 
   Future<void> test_error() async {
-    final _source = newSource('test.dart', source);
+    final _source = newSource(source);
     final allErrors = await getAllErrors(_source);
     expect(
       allErrors,
@@ -115,7 +115,7 @@ part 'test.over_react.g.dart';
   }
 
   Future<void> test_errorFix() async {
-    var _source = newSource('test.dart', source);
+    var _source = newSource(source);
     final selection = createSelection(_source, "#part 'test.over_react.g.dart';#");
     final errorFix = await expectSingleErrorFix(selection);
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -145,7 +145,7 @@ ${BoilerplateValidatorDiagnosticTest.boilerplateThatRequiresGeneratedPart}
 ''';
 
   Future<void> test_error() async {
-    final _source = newSource('test.dart', source);
+    final _source = newSource(source);
     final allErrors = await getAllErrors(_source);
     expect(
       allErrors,
@@ -161,7 +161,7 @@ ${BoilerplateValidatorDiagnosticTest.boilerplateThatRequiresGeneratedPart}
   }
 
   Future<void> test_errorFix() async {
-    var _source = newSource('test.dart', source);
+    var _source = newSource(source);
     final selection = createSelection(_source, "#part 'invalid_generated_part_filename.over_react.g.dart';#");
     final errorFix = await expectSingleErrorFix(selection);
     expect(errorFix.fixes.single.change.selection, isNull);
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/callback_ref_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/callback_ref_test.dart
index c7b1b103a..03d4ab916 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/callback_ref_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/callback_ref_test.dart
@@ -200,13 +200,13 @@ final UsesCallbackRef = uiFunction<UiProps>(
 ''';
 
   Future<void> test_blockFnBodyRefAssignment() async {
-    final source = newSource('test.dart', usageSourceWithinFnComponent);
+    final source = newSource(usageSourceWithinFnComponent);
     await expectSingleErrorAt(
         createSelection(source, CallbackRefDiagnosticTest.selectionToFixBlockFnBodyRefAssignment));
   }
 
   Future<void> test_blockFnBodyRefAssignmentFix() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponent);
+    var source = newSource(usageSourceWithinFnComponent);
     final errorFix = await expectSingleErrorFix(
         createSelection(source, CallbackRefDiagnosticTest.selectionToFixBlockFnBodyRefAssignment));
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -215,12 +215,12 @@ final UsesCallbackRef = uiFunction<UiProps>(
   }
 
   Future<void> test_arrowFnRefAssignmentError() async {
-    final source = newSource('test.dart', usageSourceWithinFnComponentFixedBlockFnBodyRefAssignment);
+    final source = newSource(usageSourceWithinFnComponentFixedBlockFnBodyRefAssignment);
     await expectSingleErrorAt(createSelection(source, CallbackRefDiagnosticTest.selectionToFixArrowFnRefAssignment));
   }
 
   Future<void> test_arrowFnRefAssignmentErrorFix() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponentFixedBlockFnBodyRefAssignment);
+    var source = newSource(usageSourceWithinFnComponentFixedBlockFnBodyRefAssignment);
     final errorFix = await expectSingleErrorFix(
         createSelection(source, CallbackRefDiagnosticTest.selectionToFixArrowFnRefAssignment));
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -235,7 +235,7 @@ class CallbackRefDiagnosticFnComponentTestNoFix extends CallbackRefDiagnosticTes
   get fixKindUnderTest => null;
 
   Future<void> test_tearoffFnRefAssignment() async {
-    final source = newSource('test.dart', CallbackRefDiagnosticFnComponentTest.usageSourceWithinFnComponent);
+    final source = newSource(CallbackRefDiagnosticFnComponentTest.usageSourceWithinFnComponent);
     final selection = createSelection(source, CallbackRefDiagnosticTest.selectionForTearoffRefAssignmentError);
     await expectSingleErrorAt(selection);
     // We intentionally do not want the diagnostic to suggest a fix since
@@ -316,13 +316,13 @@ class UsesCallbackRefComponent extends UiComponent2<UsesCallbackRefProps> {
 ''';
 
   Future<void> test_blockFnBodyRefAssignment() async {
-    final source = newSource('test.dart', usageSourceWithinClassComponent);
+    final source = newSource(usageSourceWithinClassComponent);
     await expectSingleErrorAt(
         createSelection(source, CallbackRefDiagnosticTest.selectionToFixBlockFnBodyRefAssignment));
   }
 
   Future<void> test_blockFnBodyRefAssignmentFix() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponent);
+    var source = newSource(usageSourceWithinClassComponent);
     final errorFix = await expectSingleErrorFix(
         createSelection(source, CallbackRefDiagnosticTest.selectionToFixBlockFnBodyRefAssignment));
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -331,12 +331,12 @@ class UsesCallbackRefComponent extends UiComponent2<UsesCallbackRefProps> {
   }
 
   Future<void> test_arrowFnRefAssignmentError() async {
-    final source = newSource('test.dart', usageSourceWithinClassComponentFixedBlockFnBodyRefAssignment);
+    final source = newSource(usageSourceWithinClassComponentFixedBlockFnBodyRefAssignment);
     await expectSingleErrorAt(createSelection(source, CallbackRefDiagnosticTest.selectionToFixArrowFnRefAssignment));
   }
 
   Future<void> test_arrowFnRefAssignmentErrorFix() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponentFixedBlockFnBodyRefAssignment);
+    var source = newSource(usageSourceWithinClassComponentFixedBlockFnBodyRefAssignment);
     final errorFix = await expectSingleErrorFix(
         createSelection(source, CallbackRefDiagnosticTest.selectionToFixArrowFnRefAssignment));
     expect(errorFix.fixes.single.change.selection, isNull);
@@ -351,7 +351,7 @@ class CallbackRefDiagnosticClassComponentTestNoFix extends CallbackRefDiagnostic
   get fixKindUnderTest => null;
 
   Future<void> test_tearoffFnRefAssignment() async {
-    final source = newSource('test.dart', CallbackRefDiagnosticClassComponentTest.usageSourceWithinClassComponent);
+    final source = newSource(CallbackRefDiagnosticClassComponentTest.usageSourceWithinClassComponent);
     final selection = createSelection(source, CallbackRefDiagnosticTest.selectionForTearoffRefAssignmentError);
     await expectSingleErrorAt(selection);
     // We intentionally do not want the diagnostic to suggest a fix since
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/create_ref_usage_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/create_ref_usage_test.dart
index 16979acaa..a63cb975d 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/create_ref_usage_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/create_ref_usage_test.dart
@@ -24,7 +24,7 @@ class CreateRefUsageDiagnosticTest extends DiagnosticTestBase {
   get fixKindUnderTest => CreateRefUsageDiagnostic.fixKind;
 
   Future<void> test_noErrorFunction() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
 
 ReactElement someFunction(Map props) {
@@ -37,7 +37,7 @@ ReactElement someFunction(Map props) {
   }
 
   Future<void> test_noErrorClassComponent() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
 
 part 'test.over_react.g.dart';
@@ -61,7 +61,7 @@ class FooComponent extends UiComponent2<FooProps> {
   }
 
   Future<void> test_noErrorUseRef() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart' hide createRef;
 
 part 'test.over_react.g.dart';
@@ -81,7 +81,7 @@ final Foo = uiFunction<FooProps>(
   }
 
   Future<void> test_noErrorNotFromOverReact() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart' hide createRef;
 
 part 'test.over_react.g.dart';
@@ -103,7 +103,7 @@ final Foo = uiFunction<FooProps>(
   /// Helper function to expect that the `createRef` usage error exists and verify that
   /// the fix will replace it with `useRef`.
   Future<void> _expectErrorAndFix(String input, String expectedOutput) async {
-    var source = newSource('test.dart', input);
+    var source = newSource(input);
     final selection = createSelection(source, "#createRef#");
 
     // Verify error.
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/duplicate_prop_cascade_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/duplicate_prop_cascade_test.dart
index 3e4de147c..1dc98cdc6 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/duplicate_prop_cascade_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/duplicate_prop_cascade_test.dart
@@ -42,7 +42,7 @@ final Custom = uiFunction<CustomProps>(
 ''';
 
   Future<void> test_noFalsePositives() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final customComponentUsage = (Custom()
@@ -68,7 +68,7 @@ final domComponentUsage = (Dom.div()
   }
 
   Future<void> test_dupeDomPropFix() async {
-    var source = newSource('test.dart', /*language=dart*/ r'''
+    var source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
 
 final domComponentUsage = (Dom.div()
@@ -94,7 +94,7 @@ final domComponentUsage = (Dom.div()
   }
 
   Future<void> test_dupeCustomPropFix() async {
-    var source = newSource('test.dart', /*language=dart*/ '''
+    var source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final componentUsage = (Custom()
@@ -125,7 +125,7 @@ final componentUsage = (Custom()
   // ********************************************************
 
   Future<void> test_dupeDomPropWithOnePrefixedKey() async {
-    var source = newSource('test.dart', /*language=dart*/ '''
+    var source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final customComponentUsage = (Custom()
@@ -150,7 +150,7 @@ final domComponentUsage = (Dom.div()
   }
 
   Future<void> test_dupeDomPropWithMultiplePrefixedKeys() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final domComponentUsage = (Dom.div()
@@ -179,7 +179,7 @@ final customComponentUsage = (Custom()
   }
 
   Future<void> test_dupeDomPropWithAllPrefixedKeys() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final domComponentUsage = (Dom.div()
@@ -208,7 +208,7 @@ final customComponentUsage = (Custom()
   }
 
   Future<void> test_dupeDomPropWithNoPrefixedKeys() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final domComponentUsage = (Dom.div()
@@ -239,7 +239,7 @@ final customComponentUsage = (Custom()
   // We currently don't support flagging dupes when a key is added using `..addProps(domProps()..key)`, but
   // we run a test here to verify that no lint is shown, and that the plugin doesn't crash.
   Future<void> test_noDupeAndNoPluginCrashWhenUsingAddPropsDomPropsAndPrefixedKey() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final domComponentUsage = (Dom.div()
@@ -270,7 +270,7 @@ final customComponentUsagePrefixed = (Custom()
   // ********************************************************
 
   Future<void> test_dupeAriaPropWithAllPrefixedKeys() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final domComponentUsage = (Dom.div()
@@ -297,7 +297,7 @@ final customComponentUsage = (Custom()
   // We currently don't support flagging dupes when a key is added using `..addProps(ariaProps()..key)`, but
   // we run a test here to verify that no lint is shown, and that the plugin doesn't crash.
   Future<void> test_noDupeAndNoPluginCrashWhenUsingAddPropsAriaProps() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final domComponentUsage = (Dom.div()
@@ -320,7 +320,7 @@ final customComponentUsage = (Custom()
   // ********************************************************
 
   Future<void> test_dupeCustomProp() async {
-    final source = newSource('test.dart', /*language=dart*/ '''
+    final source = newSource(/*language=dart*/ '''
 $customComponentDefinition
 
 final usage = (Custom()
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test.dart
index 7e6b1b37a..54ac6ba78 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test.dart
@@ -25,7 +25,7 @@ import 'exhaustive_deps_test_cases.dart' as test_cases;
 void main() {
   group('ExhaustiveDeps', () {
     const preamble = r'''
-// ignore_for_file: unused_import
+// ignore_for_file: unused_import, unused_local_variable
     
 import 'dart:html';
 
@@ -151,7 +151,7 @@ class ObjectWithWritableField {
               printOnFailure('Test case source (before adding preamble): ```\n${testCase.code}\n```');
 
               final testBase = await setUpTestBase(testCase);
-              final source = testBase.newSource('test.dart', preamble + testCase.code);
+              final source = testBase.newSource(preamble + testCase.code);
               await testBase.expectNoErrors(source, errorFilter: errorFilter);
             });
           });
@@ -170,7 +170,7 @@ class ObjectWithWritableField {
               final expectedErrors = testCase.errors;
               expect(expectedErrors, isNotEmpty);
 
-              final source = testBase.newSource('test.dart', preamble + testCase.code);
+              final source = testBase.newSource(preamble + testCase.code);
               final errors = await testBase.getAllErrors(source, includeOtherCodes: true, errorFilter: errorFilter);
               expect(errors.dartErrors, isEmpty,
                   reason: 'Expected there to be no errors coming from the analyzer and not the plugin.'
@@ -310,7 +310,7 @@ class ObjectWithWritableField {
                     // This means that later iterations in the loop will have unexpected changes, and also their
                     // fixes won't always end up in the right places since their offsets are stale.
                     // Revert the changes to the file so that other iterations can test their fixes without interference.
-                    testBase.resourceProvider.updateFile(p.normalize(source.uri.toFilePath()), sourceBeforeFixes);
+                    testBase.modifyFile(p.normalize(source.uri.toFilePath()), sourceBeforeFixes);
                   }
                 }
               }
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test_cases.dart b/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test_cases.dart
index f5d653c22..f59862863 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test_cases.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/exhaustive_deps_test_cases.dart
@@ -620,8 +620,8 @@ final Map<String, List<Map<String, Object>>> tests = {
     },
     {
       'code': r'''
-        StateHook<T> useFunnyState<T>(T initialState) {}
-        ReducerHook<T, dynamic, dynamic> useFunnyReducer<T>(dynamic reducer, T initialState) {}
+        StateHook<T> useFunnyState<T>(T initialState) => useState(initialState);
+        ReducerHook<T, dynamic, dynamic> useFunnyReducer<T>(dynamic reducer, T initialState) => useReducer(reducer, initialState);
         dynamic useSomeOtherRefyThing() => null;
         final MyComponent = uiFunction<TestProps>((props) {
           var maybeRef2 = props.maybeRef2;
@@ -687,8 +687,8 @@ final Map<String, List<Map<String, Object>>> tests = {
     },
     {
       'code': r'''
-        StateHook<T> useFunnyState<T>(T initialState) {}
-        ReducerHook<T, dynamic, dynamic> useFunnyReducer<T>(dynamic reducer, T initialState) {}
+        StateHook<T> useFunnyState<T>(T initialState) => useState(initialState);
+        ReducerHook<T, dynamic, dynamic> useFunnyReducer<T>(dynamic reducer, T initialState) => useReducer(reducer, initialState);
         dynamic useSomeOtherRefyThing() => null;
         final MyComponent = uiFunction<TestProps>((props) {
           var maybeRef2 = props.maybeRef2;
@@ -1382,8 +1382,8 @@ final Map<String, List<Map<String, Object>>> tests = {
     },
     {
       'code': r'''
-        final MyComponent = uiFunction<TestProps>((_) {
-          final foo = true ? "fine" : "also fine";
+        final MyComponent = uiFunction<TestProps>((props) {
+          final foo = props.isEditMode ? "fine" : "also fine";
           return useMemo(() => foo, [foo]);
         }, null);
       ''',
@@ -2351,7 +2351,7 @@ final Map<String, List<Map<String, Object>>> tests = {
           final local = someFunc();
           useEffect(() {
             print(local);
-            // ignore: undefined_identifier
+            // ignore: undefined_identifier, not_iterable_spread
           }, [local, ...dependencies]);
         }, null);
       ''',
@@ -5737,6 +5737,7 @@ final Map<String, List<Map<String, Object>>> tests = {
     },
     {
       'code': r'''
+        // ignore_for_file: dead_code
         final MyComponent = uiFunction<TestProps>((props) {
           final handleNext1 = () {
             print('hello');
@@ -5762,11 +5763,12 @@ final Map<String, List<Map<String, Object>>> tests = {
       'errors': [
         {
           'message':
-              'The \'handleNext1\' function makes the dependencies of useEffect Hook (at line 11) change on every render. To fix this, wrap the definition of \'handleNext1\' in its own useCallback() Hook.',
+              'The \'handleNext1\' function makes the dependencies of useEffect Hook (at line 12) change on every render. To fix this, wrap the definition of \'handleNext1\' in its own useCallback() Hook.',
           'suggestions': [
             {
               'desc': 'Wrap the definition of \'handleNext1\' in its own useCallback() Hook.',
               'output': r'''
+                // ignore_for_file: dead_code
                 final MyComponent = uiFunction<TestProps>((props) {
                   final handleNext1 = useCallback(() {
                     print('hello');
@@ -5789,11 +5791,12 @@ final Map<String, List<Map<String, Object>>> tests = {
         },
         {
           'message':
-              'The \'handleNext1\' function makes the dependencies of useEffect Hook (at line 15) change on every render. To fix this, wrap the definition of \'handleNext1\' in its own useCallback() Hook.',
+              'The \'handleNext1\' function makes the dependencies of useEffect Hook (at line 16) change on every render. To fix this, wrap the definition of \'handleNext1\' in its own useCallback() Hook.',
           'suggestions': [
             {
               'desc': 'Wrap the definition of \'handleNext1\' in its own useCallback() Hook.',
               'output': r'''
+                // ignore_for_file: dead_code
                 final MyComponent = uiFunction<TestProps>((props) {
                   final handleNext1 = useCallback(() {
                     print('hello');
@@ -5816,11 +5819,12 @@ final Map<String, List<Map<String, Object>>> tests = {
         },
         {
           'message':
-              'The \'handleNext2\' function makes the dependencies of useEffect Hook (at line 11) change on every render. To fix this, wrap the definition of \'handleNext2\' in its own useCallback() Hook.',
+              'The \'handleNext2\' function makes the dependencies of useEffect Hook (at line 12) change on every render. To fix this, wrap the definition of \'handleNext2\' in its own useCallback() Hook.',
           'suggestions': [
             {
               'desc': 'Wrap the definition of \'handleNext2\' in its own useCallback() Hook.',
               'output': r'''
+                // ignore_for_file: dead_code
                 final MyComponent = uiFunction<TestProps>((props) {
                   final handleNext1 = () {
                     print('hello');
@@ -5843,11 +5847,12 @@ final Map<String, List<Map<String, Object>>> tests = {
         },
         {
           'message':
-              'The \'handleNext2\' function makes the dependencies of useEffect Hook (at line 15) change on every render. To fix this, wrap the definition of \'handleNext2\' in its own useCallback() Hook.',
+              'The \'handleNext2\' function makes the dependencies of useEffect Hook (at line 16) change on every render. To fix this, wrap the definition of \'handleNext2\' in its own useCallback() Hook.',
           'suggestions': [
             {
               'desc': 'Wrap the definition of \'handleNext2\' in its own useCallback() Hook.',
               'output': r'''
+                // ignore_for_file: dead_code
                 final MyComponent = uiFunction<TestProps>((props) {
                   final handleNext1 = () {
                     print('hello');
@@ -7030,8 +7035,8 @@ final Map<String, List<Map<String, Object>>> tests = {
     /* (1 case previously here involving class expressions was removed, since there is no equivalent in Dart) */
     {
       'code': r'''
-        final Component = uiFunction<TestProps>((_) {
-          final foo = true ? {} : "fine";
+        final Component = uiFunction<TestProps>((props) {
+          final foo = props.isEditMode ? {} : "fine";
           useMemo(() => foo, [foo]);
         }, null);
       ''',
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/forward_only_dom_props_to_dom_builders_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/forward_only_dom_props_to_dom_builders_test.dart
index 546e7ba39..91ba320ea 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/forward_only_dom_props_to_dom_builders_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/forward_only_dom_props_to_dom_builders_test.dart
@@ -59,7 +59,7 @@ final DomWrapperFn = uiFunction<UiProps>(
 ''';
 
   Future<void> test_classComponentUsageErrorAndFix() async {
-    var source = newSource('test.dart', usageSourceWithinClassComponent(fixed: false));
+    var source = newSource(usageSourceWithinClassComponent(fixed: false));
     final errorFix = await expectSingleErrorFix(createSelection(source, "..modifyProps(#addUnconsumedProps#)"));
     expect(errorFix.fixes.single.change.selection, isNull);
     source = applyErrorFixes(errorFix, source);
@@ -67,7 +67,7 @@ final DomWrapperFn = uiFunction<UiProps>(
   }
 
   Future<void> test_fnComponentUsageErrorAndFix() async {
-    var source = newSource('test.dart', usageSourceWithinFnComponent(fixed: false));
+    var source = newSource(usageSourceWithinFnComponent(fixed: false));
     final errorFix = await expectSingleErrorFix(createSelection(source, "..#addUnconsumedProps#(props, const [])"));
     expect(errorFix.fixes.single.change.selection, isNull);
     source = applyErrorFixes(errorFix, source);
diff --git a/tools/analyzer_plugin/test/integration/diagnostics/non_defaulted_prop_test.dart b/tools/analyzer_plugin/test/integration/diagnostics/non_defaulted_prop_test.dart
index fd25a9aef..edd1f6bfe 100644
--- a/tools/analyzer_plugin/test/integration/diagnostics/non_defaulted_prop_test.dart
+++ b/tools/analyzer_plugin/test/integration/diagnostics/non_defaulted_prop_test.dart
@@ -24,7 +24,7 @@ class NonDefaultedPropDiagnosticTest extends DiagnosticTestBase {
   get fixKindUnderTest => NonDefaultedPropDiagnostic.fixKind;
 
   Future<void> test_noErrorDefaultUsed() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
 
 part 'test.over_react.g.dart';
@@ -49,7 +49,7 @@ final Foo = uiFunction<FooProps>(
   }
 
   Future<void> test_noErrorSameNameButNotDefault() async {
-    final source = newSource('test.dart', /*language=dart*/ r'''
+    final source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
 
 part 'test.over_react.g.dart';
@@ -61,6 +61,7 @@ mixin FooProps on UiProps {
 
 final Foo = uiFunction<FooProps>(
   (props) {
+    // ignore: unused_local_variable
     final content = 'abc';
     
     return (Dom.div()
@@ -92,7 +93,7 @@ final Foo = uiFunction<FooProps>(
   _\$FooConfig, // ignore: undefined_identifier
 );
 ''';
-    var source = newSource('test.dart', contents('props.content'));
+    var source = newSource(contents('props.content'));
     final selection = createSelection(source, "(#props.content#)");
 
     // Verify error.
@@ -124,7 +125,7 @@ final Foo = uiFunction<FooProps>(
   _\$FooConfig, // ignore: undefined_identifier
 );
 ''';
-    var source = newSource('test.dart', contents('props.content'));
+    var source = newSource(contents('props.content'));
     final selection = createSelection(source, "(#props.content#)");
 
     // Verify error.
@@ -138,7 +139,7 @@ final Foo = uiFunction<FooProps>(
   }
 
   Future<void> test_multipleErrorsAndFixes() async {
-    var source = newSource('test.dart', /*language=dart*/ r'''
+    var source = newSource(/*language=dart*/ r'''
 import 'package:over_react/over_react.dart';
 
 part 'test.over_react.g.dart';
@@ -152,11 +153,14 @@ mixin FooProps on UiProps {
 
 final Foo = uiFunction<FooProps>(
   (props) {
+    // ignore: unused_local_variable
     final fooId = props.fooId ?? 'abc';
+    // ignore: unused_local_variable
     final name = props.name ?? 'Jane';
     
     // Some other logic
     void helperFunction() => print('hello');
+    // ignore: unused_local_variable
     const a = 25;
     // Some other logic
     
@@ -202,11 +206,14 @@ mixin FooProps on UiProps {
 
 final Foo = uiFunction<FooProps>(
   (props) {
+    // ignore: unused_local_variable
     final fooId = props.fooId ?? 'abc';
+    // ignore: unused_local_variable
     final name = props.name ?? 'Jane';
     
     // Some other logic
     void helperFunction() => print('hello');
+    // ignore: unused_local_variable
     const a = 25;
     // Some other logic
     
diff --git a/tools/analyzer_plugin/test/integration/stubs.dart b/tools/analyzer_plugin/test/integration/stubs.dart
index 8b15333b7..6af6f0050 100644
--- a/tools/analyzer_plugin/test/integration/stubs.dart
+++ b/tools/analyzer_plugin/test/integration/stubs.dart
@@ -1,9 +1,11 @@
-import 'package:analyzer/file_system/file_system.dart';
-import 'package:analyzer/src/dart/analysis/driver.dart';
+import 'package:analyzer/dart/analysis/analysis_context.dart';
+import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/file_system/overlay_file_system.dart';
 import 'package:analyzer_plugin/channel/channel.dart';
 import 'package:analyzer_plugin/plugin/plugin.dart';
 import 'package:analyzer_plugin/protocol/protocol.dart';
-import 'package:analyzer_plugin/protocol/protocol_generated.dart';
+import 'package:over_react_analyzer_plugin/src/async_plugin_apis/assist.dart';
+import 'package:over_react_analyzer_plugin/src/async_plugin_apis/diagnostic.dart';
 import 'package:over_react_analyzer_plugin/src/plugin.dart';
 
 import 'test_bases/assist_test_base.dart';
@@ -20,19 +22,173 @@ class StubChannel implements PluginCommunicationChannel {
   dynamic noSuchMethod(Invocation invocation) {}
 }
 
+/// A stubbed ServerPlugin base class to use for testing, so that we can ensure its AnalysisContextCollection isn't
+/// being used instead of the one we've set up in tests.
+class StubServerPlugin implements ServerPlugin {
+  @override
+  get channel => throw UnimplementedError();
+
+  @override
+  get priorityPaths => throw UnimplementedError();
+
+  @override
+  set priorityPaths(value) => throw UnimplementedError();
+
+  @override
+  afterNewContextCollection({required contextCollection}) => throw UnimplementedError();
+
+  @override
+  analyzeFile({required analysisContext, required path}) => throw UnimplementedError();
+
+  @override
+  analyzeFiles({required analysisContext, required paths}) => throw UnimplementedError();
+
+  @override
+  beforeContextCollectionDispose({required contextCollection}) => throw UnimplementedError();
+
+  @override
+  get contactInfo => throw UnimplementedError();
+
+  @override
+  contentChanged(paths) => throw UnimplementedError();
+
+  @override
+  createByteStore() => throw UnimplementedError();
+
+  @override
+  get fileGlobsToAnalyze => throw UnimplementedError();
+
+  @override
+  flushAnalysisState({elementModels = true}) => throw UnimplementedError();
+
+  @override
+  getResolvedUnitResult(path) => throw UnimplementedError();
+
+  @override
+  handleAffectedFiles({required analysisContext, required paths}) => throw UnimplementedError();
+
+  @override
+  handleAnalysisGetNavigation(parameters) => throw UnimplementedError();
+
+  @override
+  handleAnalysisHandleWatchEvents(parameters) => throw UnimplementedError();
+
+  @override
+  handleAnalysisSetContextRoots(parameters) => throw UnimplementedError();
+
+  @override
+  handleAnalysisSetPriorityFiles(parameters) => throw UnimplementedError();
+
+  @override
+  handleAnalysisSetSubscriptions(parameters) => throw UnimplementedError();
+
+  @override
+  handleAnalysisUpdateContent(parameters) => throw UnimplementedError();
+
+  @override
+  handleCompletionGetSuggestions(parameters) => throw UnimplementedError();
+
+  @override
+  handleEditGetAssists(parameters) => throw UnimplementedError();
+
+  @override
+  handleEditGetAvailableRefactorings(parameters) => throw UnimplementedError();
+
+  @override
+  handleEditGetFixes(parameters) => throw UnimplementedError();
+
+  @override
+  handleEditGetRefactoring(parameters) => throw UnimplementedError();
+
+  @override
+  handleKytheGetKytheEntries(parameters) => throw UnimplementedError();
+
+  @override
+  handlePluginShutdown(parameters) => throw UnimplementedError();
+
+  @override
+  handlePluginVersionCheck(parameters) => throw UnimplementedError();
+
+  @override
+  isCompatibleWith(serverVersion) => throw UnimplementedError();
+
+  @override
+  get name => throw UnimplementedError();
+
+  @override
+  void onDone() {}
+
+  @override
+  void onError(exception, stackTrace) {}
+
+  @override
+  get resourceProvider => throw UnimplementedError();
+
+  @override
+  sendFoldingNotification(path) => throw UnimplementedError();
+
+  @override
+  sendHighlightsNotification(path) => throw UnimplementedError();
+
+  @override
+  sendNavigationNotification(path) => throw UnimplementedError();
+
+  @override
+  void sendNotificationsForFile(path) {}
+
+  @override
+  void sendNotificationsForSubscriptions(subscriptions) {}
+
+  @override
+  sendOccurrencesNotification(path) => throw UnimplementedError();
+
+  @override
+  sendOutlineNotification(path) => throw UnimplementedError();
+
+  @override
+  void start(channel) => throw UnimplementedError();
+
+  @override
+  get subscriptionManager => throw UnimplementedError();
+
+  @override
+  get version => throw UnimplementedError();
+}
+
 /// A concrete [ServerPlugin] implementation designed for use in testing a
-/// single assist or diagnostic contributor against a real-ish [AnalysisDriver].
+/// single assist or diagnostic contributor against real-ish AnalysisContexts.
 ///
 /// Tests should not use, extend, or implement this class directly. Instead,
 /// extend the contributor-specific test base class, like [AssistTestBase].
-class PluginForTest extends OverReactAnalyzerPluginBase {
-  final AnalysisDriver testDriver;
+class PluginForTest extends StubServerPlugin
+    with
+        DiagnosticMixin,
+        AsyncAssistsMixin,
+        AsyncDartAssistsMixin,
+        OverReactAnalyzerPluginBase {
+  @override
+  late PluginCommunicationChannel channel;
+
+  @override
+  late OverlayResourceProvider resourceProvider;
 
-  PluginForTest(this.testDriver, ResourceProvider resourceProvider) : super(resourceProvider);
+  late Future<ResolvedUnitResult> Function(String path)? handleGetResolvedUnitResult;
 
   @override
-  String get name => 'over_react (for test)';
+  Future<ResolvedUnitResult> getResolvedUnitResult(String path) =>
+      handleGetResolvedUnitResult?.call(path) ?? (throw UnimplementedError());
+
+  @override
+  Future<void> analyzeFile({required AnalysisContext analysisContext, required String path}) =>
+      throw UnimplementedError();
+
+  @override
+  Future<void> analyzeFiles({required AnalysisContext analysisContext, required List<String> paths}) =>
+      throw UnimplementedError();
 
   @override
-  AnalysisDriverGeneric createAnalysisDriver(ContextRoot contextRoot) => testDriver;
+  Future<void> contentChanged(List<String> paths) => throw UnimplementedError();
+
+  @override
+  String get name => 'over_react (for test)';
 }
diff --git a/tools/analyzer_plugin/test/integration/test_bases/analysis_driver_test_base.dart b/tools/analyzer_plugin/test/integration/test_bases/analysis_driver_test_base.dart
index 2ac904583..c183cb91f 100644
--- a/tools/analyzer_plugin/test/integration/test_bases/analysis_driver_test_base.dart
+++ b/tools/analyzer_plugin/test/integration/test_bases/analysis_driver_test_base.dart
@@ -1,25 +1,12 @@
 import 'dart:io';
 
-import 'package:analyzer/dart/analysis/features.dart';
-import 'package:analyzer/file_system/file_system.dart';
-import 'package:analyzer/file_system/memory_file_system.dart';
-import 'package:analyzer/file_system/physical_file_system.dart';
-import 'package:analyzer/src/context/packages.dart';
-import 'package:analyzer/src/dart/analysis/analysis_context_collection.dart';
-import 'package:analyzer/src/dart/analysis/byte_store.dart';
-import 'package:analyzer/src/dart/analysis/driver.dart' show AnalysisDriver, AnalysisDriverScheduler;
-import 'package:analyzer/src/dart/analysis/performance_logger.dart';
-import 'package:analyzer/src/generated/engine.dart';
-import 'package:analyzer/src/generated/source.dart';
-import 'package:analyzer/src/source/package_map_resolver.dart';
-import 'package:analyzer/src/test_utilities/mock_sdk.dart';
-import 'package:collection/collection.dart' show IterableExtension;
+import 'package:analyzer/file_system/file_system.dart' show ResourceProvider;
+// ignore: implementation_imports
+import 'package:analyzer/src/generated/source.dart' show Source;
 import 'package:meta/meta.dart';
-import 'package:package_config/package_config.dart';
 import 'package:path/path.dart' as p;
-import 'package:pub_semver/pub_semver.dart';
-import 'package:test/test.dart';
 
+import '../../util/shared_analysis_context.dart';
 import 'assist_test_base.dart';
 
 /// Test base that handles constructing an analysis server plugin designed for
@@ -31,134 +18,71 @@ import 'assist_test_base.dart';
 /// extend a test base for the specific type of contributor, like
 /// [AssistTestBase].
 abstract class AnalysisDriverTestBase {
-  /// The list of packages that are dependencies of this
-  /// `over_react_analyzer_plugin` package and are required for contributor
-  /// integration test sources.
-  ///
-  /// Any package in this list will be copied from the physical pub-cache into
-  /// the [MemoryResourceProvider] and the [AnalysisDriver] will be configured
-  /// with a [PackageMapUriResolver] that knows where these packages are so that
-  /// test sources can import from them.
-  static const _realPackagesToCopyIntoResourceProvider = [
-    // FIXME add all transitive deps of over_react (or do that in the package config logic)
-    'over_react',
-    'react',
-    'collection',
-  ];
-
-  /// The analysis driver that computes analysis results for the test sources
-  /// created via [newSource] that are then used by the plugin contributors
-  /// under test.
-  AnalysisDriver get analysisDriver => _analysisDriver!;
-  AnalysisDriver? _analysisDriver;
-
   /// Provider of all resources created during and needed for tests.
-  MemoryResourceProvider get resourceProvider => _resourceProvider!;
-  MemoryResourceProvider? _resourceProvider;
-
-  /// Absolute path to the in-memory folder within which all test sources are
-  /// created.
-  String get testPath => _testPath!;
-  String? _testPath;
+  ResourceProvider get resourceProvider => _resourceProvider!;
+  ResourceProvider? _resourceProvider;
 
   /// Contents of analysis_options.yaml file.
   ///
   /// This is optional; if `null`, there will be no analysis_options.yaml file.
   String? get analysisOptionsYamlContents => null;
 
-  /// Creates and returns a new source file at [path] with optional file
-  /// [contents].
+  /// Creates and returns a new source file with the provided [contents]
+  /// within [sharedContext].
+  ///
+  /// Creates the file at [path] if it's non-null, and otherwise uses a new, unique path.
   ///
-  /// [path] must be relative; the returned source will be created within
-  /// [testPath].
-  Source newSource(String path, [String? contents]) {
-    expect(p.isAbsolute(path), isFalse, reason: 'newSource() must be called with a relative path');
-    final absolutePath = p.join(testPath, path);
-    final file = resourceProvider.newFile(absolutePath, contents ?? '');
-    return file.createSource();
+  /// If provided, [path] must be relative, and also must be unique so that it
+  /// doesn't conflict with paths created by other tests using the same [sharedContext]
+  Source newSource(String contents, {String? path}) {
+    if (path != null && p.isAbsolute(path)) {
+      throw ArgumentError.value(path, 'path', 'must be a relative path');
+    }
+    final testFilePath = sharedContext.createTestFile(contents, filename: path);
+    return resourceProvider.getFile(testFilePath).createSource();
   }
 
-  /// Returns the absolute path for [source].
-  String sourcePath(Source source) => resourceProvider.convertPath(source.uri.path);
-
-  @mustCallSuper
-  Future<void> setUp() async {
-    // Based on https://github.com/dart-lang/angular/blob/832c8df2c54415e8b6e68886cd3d8c293ef9874c/angular_analyzer_plugin/test/analyzer_base.dart#L62-L89
+  void modifyFile(String path, String contents) {
+    resourceProvider.getFile(path).writeAsStringSync(contents);
+  }
 
-    _resourceProvider = MemoryResourceProvider();
+  /// Returns the absolute path for [source].
+  String sourcePath(Source source) => source.uri.toFilePath();
 
-    final sdk = MockSdk(resourceProvider: resourceProvider);
-    final packageMap = {
-      for (final packageName in _realPackagesToCopyIntoResourceProvider)
-        packageName: [await _loadRealPackage(packageName, resourceProvider)],
-    };
+  SharedAnalysisContext? _sharedContext;
 
-    // Setup a testing directory. All calls to [newSource] will create files
-    // within this directory.
-    _testPath = resourceProvider.newFolder('/test').path;
+  SharedAnalysisContext get sharedContext => _sharedContext!;
 
-    // Add a analysis_options.yaml file to the [resourceProvider] if the contents are specified.
-    // If this isn't set up here, `AnalysisContext.optionsFile` will be null even if the file is added later.
-    final contents = analysisOptionsYamlContents;
-    if (contents != null) {
-      final absolutePath = p.join(testPath, 'analysis_options.yaml');
-      resourceProvider.newFile(absolutePath, contents);
+  @mustCallSuper
+  Future<void> setUp() async {
+    // TODO once we're running tests optionally on null-safe code? Or maybe language version comments in source files instead?
+    // final defaultContext = isNullSafe ? SharedAnalysisContext.overReactNullSafe : SharedAnalysisContext.overReactNonNullSafe;
+    final defaultContext = SharedAnalysisContext.overReact;
+    if (analysisOptionsYamlContents == null) {
+      _sharedContext = defaultContext;
+    } else {
+      // Create a copy since modifying the original context would interfere with other test.
+      //
+      // Make sure the copy is on the same level as the original so that we don't have to mess with relative paths
+      // in the pubspec (e.g., to the over_react dependency).
+      // Original: test/test_fixtures/over_react_project/
+      // Copy: test/temporary_test_fixtures/<generated_name>/
+      final parentDir = p.canonicalize(p.join(defaultContext.contextRootPath, '../../temporary_test_fixtures'));
+      _sharedContext = SharedAnalysisContext.createTemporaryCopy(defaultContext, parentDir);
+      File(p.join(sharedContext.contextRootPath, 'analysis_options.yaml'))
+          .writeAsStringSync(analysisOptionsYamlContents!);
     }
 
-    // Disable null safety
-    final languageVersion = Version.parse('2.7.0');
-    final languageConstraint = VersionConstraint.compatibleWith(languageVersion);
-    final featureSet = FeatureSet.fromEnableFlags2(sdkLanguageVersion: languageVersion, flags: []);
-
-    final logger = PerformanceLog(StringBuffer());
-    final analysisScheduler = AnalysisDriverScheduler(logger)..start();
-    _analysisDriver = AnalysisDriver.tmp1(
-      scheduler: analysisScheduler,
-      logger: logger,
-      resourceProvider: resourceProvider,
-      byteStore: MemoryByteStore(),
-      sourceFactory: SourceFactory([
-        DartUriResolver(sdk),
-        PackageMapUriResolver(resourceProvider, packageMap),
-        ResourceUriResolver(resourceProvider),
-      ]),
-      analysisOptions: AnalysisOptionsImpl()
-        ..sdkVersionConstraint = languageConstraint
-        ..contextFeatures = featureSet
-        ..nonPackageLanguageVersion = languageVersion
-        ..nonPackageFeatureSet = featureSet,
-      packages: Packages.empty,
-    );
-
-    final contextCollection = AnalysisContextCollectionImpl(
-        includedPaths: [testPath], resourceProvider: resourceProvider, sdkPath: resourceProvider.convertPath('/sdk'));
-    _analysisDriver!.analysisContext = contextCollection.contextFor(testPath);
+    await sharedContext.warmUpAnalysis();
+    _resourceProvider = sharedContext.collection.contexts.single.currentSession.resourceProvider;
   }
 
   @mustCallSuper
   void tearDown() {
-    _analysisDriver?.dispose();
-    _analysisDriver = null;
     _resourceProvider = null;
-    _testPath = null;
-  }
-
-  /// Returns the parsed package config from the
-  /// `.dart_tool/package_config.json` file for the
-  /// `over_react_analyzer_plugin` package.
-  static Future<PackageConfig> _getRootPackageConfig() async =>
-      (_realPackageConfig ??= await findPackageConfig(Directory.current, recurse: false))!;
-  static PackageConfig? _realPackageConfig;
-
-  /// Finds the source of [packageName] and copies the physical resources into
-  /// the [memory] resoure provider at the `/packages/$packageName` location.
-  static Future<Folder> _loadRealPackage(String packageName, MemoryResourceProvider memory) async {
-    final package = (await _getRootPackageConfig()).packages.firstWhereOrNull((pkg) => pkg.name == packageName)!;
-    expect(package, isNotNull,
-        reason: 'Could not load "$packageName" into MemoryResourceProvider because it is not a dependency.');
-    final physicalRoot = p.normalize(package.packageUriRoot.toFilePath());
-    final memoryRoot = p.normalize('/packages/$packageName');
-    PhysicalResourceProvider.INSTANCE.getFolder(physicalRoot).copyTo(memory.getFolder(memoryRoot));
-    return memory.getFolder(p.join(memoryRoot, 'lib'));
+    if (_sharedContext != null && sharedContext.isTemporaryCopy) {
+      Directory(sharedContext.contextRootPath).deleteSync(recursive: true);
+    }
+    _sharedContext = null;
   }
 }
diff --git a/tools/analyzer_plugin/test/integration/test_bases/assist_test_base.dart b/tools/analyzer_plugin/test/integration/test_bases/assist_test_base.dart
index a637fc75b..61a1391ee 100644
--- a/tools/analyzer_plugin/test/integration/test_bases/assist_test_base.dart
+++ b/tools/analyzer_plugin/test/integration/test_bases/assist_test_base.dart
@@ -26,7 +26,7 @@ abstract class AssistTestBase extends ServerPluginContributorTestBase {
   /// [selectionTargets] does not produce a single assist matching
   /// [assistKindUnderTest].
   Future<void> expectAllSelectionsProduceSingleAssist(String sourceContents, List<String> selectionTargets) async {
-    final source = newSource('test.dart', sourceContents);
+    final source = newSource(sourceContents);
     for (final target in selectionTargets) {
       final selection = createSelection(source, target);
       final assists = await _getAllAssists(selection);
@@ -56,7 +56,7 @@ abstract class AssistTestBase extends ServerPluginContributorTestBase {
   /// Returns all assists produced at [selection].
   Future<List<PrioritizedSourceChange>> _getAllAssists(SourceSelection selection) async {
     final parameters = EditGetAssistsParams(
-        resourceProvider.convertPath(selection.source.uri.path), selection.offset, selection.length);
+        selection.source.uri.toFilePath(), selection.offset, selection.length);
     return (await testPlugin.handleEditGetAssists(parameters))
         .assists
         .where((psc) => psc.change.id == assistKindUnderTest.id)
diff --git a/tools/analyzer_plugin/test/integration/test_bases/diagnostic_test_base.dart b/tools/analyzer_plugin/test/integration/test_bases/diagnostic_test_base.dart
index 3c7593fb3..33647808f 100644
--- a/tools/analyzer_plugin/test/integration/test_bases/diagnostic_test_base.dart
+++ b/tools/analyzer_plugin/test/integration/test_bases/diagnostic_test_base.dart
@@ -8,6 +8,7 @@ import 'package:test/test.dart';
 import '../matchers.dart';
 import 'server_plugin_contributor_test_base.dart';
 
+// ignore: implementation_imports
 export 'package:analyzer/src/generated/source.dart' show Source;
 
 /// Test base for integration tests that exercise a single diagnostic
@@ -74,7 +75,7 @@ abstract class DiagnosticTestBase extends ServerPluginContributorTestBase {
   /// Fails the test if any selection of [sourceContents] from
   /// [selectionTargets] does not produce a single assist.
   Future<void> expectAllSelectionsProduceAtLeastOneError(String sourceContents, List<String> selectionTargets) async {
-    final source = newSource('test.dart', sourceContents);
+    final source = newSource(sourceContents);
     for (final target in selectionTargets) {
       final selection = createSelection(source, target);
       await expectSingleErrorFix(selection);
diff --git a/tools/analyzer_plugin/test/integration/test_bases/server_plugin_contributor_test_base.dart b/tools/analyzer_plugin/test/integration/test_bases/server_plugin_contributor_test_base.dart
index aa73bd29d..9922a39d9 100644
--- a/tools/analyzer_plugin/test/integration/test_bases/server_plugin_contributor_test_base.dart
+++ b/tools/analyzer_plugin/test/integration/test_bases/server_plugin_contributor_test_base.dart
@@ -1,6 +1,8 @@
-import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/file_system/overlay_file_system.dart';
+// ignore: implementation_imports
+import 'package:analyzer/src/generated/source.dart' show Source, SourceRange;
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
-import 'package:analyzer_plugin/protocol/protocol_generated.dart';
 import 'package:meta/meta.dart';
 import 'package:path/path.dart' as p;
 import 'package:test/test.dart';
@@ -74,7 +76,8 @@ abstract class ServerPluginContributorTestBase extends AnalysisDriverTestBase {
       resourceProvider.getFile(path).readAsStringSync(),
       [for (final fileEdit in applicableFileEdits) ...fileEdit.edits],
     );
-    final file = resourceProvider.updateFile(path, updated);
+    modifyFile(path, updated);
+    final file = resourceProvider.getFile(path);
     return file.createSource();
   }
 
@@ -149,18 +152,21 @@ abstract class ServerPluginContributorTestBase extends AnalysisDriverTestBase {
     await super.setUp();
 
     _channel = StubChannel();
-    _plugin = PluginForTest(analysisDriver, resourceProvider)..start(_channel!);
-
-    // ignore: missing_required_param
-    final contextRoot = ContextRoot(testPath, []);
-    await testPlugin.handleAnalysisSetContextRoots(AnalysisSetContextRootsParams([contextRoot]));
+    _plugin = PluginForTest()
+      ..channel = _channel!
+      ..resourceProvider = OverlayResourceProvider(sharedContext.collection.contexts.single.currentSession.resourceProvider)
+      ..handleGetResolvedUnitResult = (path) async {
+        final result = await sharedContext.collection.contextFor(path).currentSession.getResolvedUnit(path);
+        if (result is ResolvedUnitResult) return result;
+
+        throw Exception('Could not resolve path $path: $result');
+      };
   }
 
   @override
   @mustCallSuper
   Future<void> tearDown() async {
     expectNoPluginErrors();
-    await _plugin?.handlePluginShutdown(PluginShutdownParams());
     _channel = null;
     _plugin = null;
     super.tearDown();
diff --git a/tools/analyzer_plugin/test/test_fixtures/over_react_project/README.md b/tools/analyzer_plugin/test/test_fixtures/over_react_project/README.md
new file mode 100644
index 000000000..e8e9cb721
--- /dev/null
+++ b/tools/analyzer_plugin/test/test_fixtures/over_react_project/README.md
@@ -0,0 +1,3 @@
+A package that depends on over_react, and can be used as a context root for tests that require a resolved analysis context with access to over_react APIs.
+
+To use, see `SharedAnalysisContext.over_react`.
diff --git a/tools/analyzer_plugin/test/test_fixtures/over_react_project/analysis_options.yaml b/tools/analyzer_plugin/test/test_fixtures/over_react_project/analysis_options.yaml
new file mode 100644
index 000000000..190747144
--- /dev/null
+++ b/tools/analyzer_plugin/test/test_fixtures/over_react_project/analysis_options.yaml
@@ -0,0 +1 @@
+# Without this file, this project will inherit analysis_options.yaml from parent directories.
diff --git a/tools/analyzer_plugin/test/test_fixtures/over_react_project/lib/analysis_warmup.dart b/tools/analyzer_plugin/test/test_fixtures/over_react_project/lib/analysis_warmup.dart
new file mode 100644
index 000000000..83a58ae5c
--- /dev/null
+++ b/tools/analyzer_plugin/test/test_fixtures/over_react_project/lib/analysis_warmup.dart
@@ -0,0 +1,8 @@
+// This file imports WSD and over_react and can be analyzed to warm up an
+// analysis context during testing.
+
+import 'package:over_react/over_react.dart';
+
+main() {
+  Dom.div()();
+}
diff --git a/tools/analyzer_plugin/test/test_fixtures/over_react_project/pubspec.yaml b/tools/analyzer_plugin/test/test_fixtures/over_react_project/pubspec.yaml
new file mode 100644
index 000000000..90d438b1a
--- /dev/null
+++ b/tools/analyzer_plugin/test/test_fixtures/over_react_project/pubspec.yaml
@@ -0,0 +1,6 @@
+name: over_react_project
+environment:
+  sdk: '>=2.11.0 <3.0.0'
+dependencies:
+  over_react:
+    path: ../../../../..
diff --git a/tools/analyzer_plugin/test/test_util.dart b/tools/analyzer_plugin/test/test_util.dart
index e3b1bb386..6abcf2d45 100644
--- a/tools/analyzer_plugin/test/test_util.dart
+++ b/tools/analyzer_plugin/test/test_util.dart
@@ -1,19 +1,13 @@
-import 'dart:convert';
-import 'dart:io';
-
-import 'package:analyzer/dart/analysis/analysis_context_collection.dart';
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/analysis/utilities.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/diagnostic/diagnostic.dart';
-import 'package:analyzer/src/dart/analysis/driver_based_analysis_context.dart' show DriverBasedAnalysisContext;
-import 'package:analyzer/file_system/overlay_file_system.dart';
-import 'package:analyzer/file_system/physical_file_system.dart';
 import 'package:over_react_analyzer_plugin/src/component_usage.dart';
 import 'package:over_react_analyzer_plugin/src/error_filtering.dart';
 import 'package:over_react_analyzer_plugin/src/util/ast_util.dart';
 import 'package:over_react_analyzer_plugin/src/util/ignore_info.dart';
-import 'package:path/path.dart' as p;
+
+import 'util/shared_analysis_context.dart';
 
 /// Parses [dartSource] and returns the unresolved AST, throwing if there are any syntax errors.
 CompilationUnit parseAndGetUnit(String dartSource) {
@@ -70,142 +64,23 @@ FluentComponentUsage parseAndGetComponentUsage(String dartSource) {
 }
 
 /// Parses [dartSource] and returns the resolved AST, throwing if there are any static analysis errors.
-Future<ResolvedUnitResult> parseAndGetResolvedUnit(String dartSource, {String path = 'dartSource.dart'}) async {
-  final results = await parseAndGetResolvedUnits({path: dartSource});
-  return results.values.single;
-}
-
-// Reuse an analysis context across multiple calls,
-// which is much faster than spinning up a new one each time
-// when resolving files.
-var _hasInitializedSharedCollection = false;
-late AnalysisContextCollection _sharedCollection;
-late OverlayResourceProvider _sharedResourceProvider;
-var _dartSourcePathsAddedInPreviousCall = <String>[];
-
-/// Parses a collection of Dart sources and returns the resolved ASTs,
-/// throwing if there are any static analysis errors.
-///
-/// Useful when you need multiple files that reference each other.
-///
-/// Example:
-/// ```dart
-///  final results = await parseAndGetResolvedUnits({
-///    'foo.dart': r'''
-///      class Foo {}
-///    ''',
-///
-///    'bar.dart': r'''
-///      import 'foo.dart';
-///      class Bar extends Foo {}
-///    ''',
-///  });
-///
-///  final barResolveResult = results['bar.dart'];
-///  final barElement = barResolveResult.unit.declaredElement.getType('Bar');
-///  print(barElement.allSupertypes); // [Foo, Object]
-/// ```
-Future<Map<String, ResolvedUnitResult>> parseAndGetResolvedUnits(Map<String, String> dartSourcesByPath) async {
-  // Must be absolute.
-  const pathPrefix = '/fake_in_memory_path';
-
-  String transformPath(String path) => p.join(pathPrefix, path);
-
-  final dartSourcesByAbsolutePath = dartSourcesByPath.map((key, value) => MapEntry(transformPath(key), value));
-
-  if (!_hasInitializedSharedCollection) {
-    _sharedResourceProvider = OverlayResourceProvider(PhysicalResourceProvider.INSTANCE);
-
-    // Create a fake in memory package that opts out of null safety
-    // TODO clean this up, perhaps use SharedAnalysisContextCollection from over_react_codemod
-    const packageName = 'package_depending_on_over_react';
-    _sharedResourceProvider.setOverlay(transformPath('pubspec.yaml'),
-        content: '''
-  name: $packageName
-  publish_to: none
-  environment:
-    # Opt out of null safety since it gets in our way for these tests
-    sdk: '>=2.11.0 <3.0.0'
-  dependencies:
-    over_react: ^4.3.1
-  ''',
-        modificationStamp: 0);
-    // Steal the packages file from this project, which depends on over_react
-    final currentPackageConfig = File('.dart_tool/package_config.json').readAsStringSync();
-    final updatedConfig = jsonDecode(currentPackageConfig) as Map;
-    var updatedPackages = (updatedConfig['packages'] as List).cast<Map>()
-      // Need to get rid of this config so its rootUri doesn't cause it to get used for this package.
-      ..removeSingleWhere((package) => package['name'] == 'over_react_analyzer_plugin');
-    updatedPackages = updatedPackages.map((e) {
-      // Transform any relative paths to absolute ones, since they're relative to
-      // over_react_analyzer_plugin and not this new fake package.
-      var rootUri = e['rootUri'] as String;
-      if (!Uri.parse(rootUri).hasScheme) {
-        // fixme verify relative to pubspec.yaml
-        rootUri = Uri.file(p.canonicalize(p.absolute('pubspec.yaml', rootUri))).toString();
-      }
-      return <dynamic, dynamic>{
-        ...e,
-        'rootUri': rootUri,
-      };
-    }).toList()
-      ..add(<String, String>{
-        "name": packageName,
-        "rootUri": "../",
-        "packageUri": "lib/",
-        // Opt out of null safety since it gets in our way for these tests
-        "languageVersion": "2.7",
-      });
-    updatedConfig['packages'] = updatedPackages;
-    _sharedResourceProvider.setOverlay(transformPath('.dart_tool/package_config.json'),
-        content: jsonEncode(updatedConfig), modificationStamp: 0);
-
-    _sharedCollection = AnalysisContextCollection(
-      includedPaths: [pathPrefix],
-      resourceProvider: _sharedResourceProvider,
-    );
-    _hasInitializedSharedCollection = true;
-  }
-
-  // Clean up overlays for previous calls, and let the driver know the file has changed so it doesn't cache the result
-  // if this call uses files of the same name.
-  // Do this before each call instead of after getting the resolved unit
-  // so that the session associate with the result remains valid after this function returns.
-  for (final absolutePath in _dartSourcePathsAddedInPreviousCall) {
-    _sharedResourceProvider.removeOverlay(absolutePath);
-    (_sharedCollection.contextFor(absolutePath) as DriverBasedAnalysisContext).driver.removeFile(absolutePath);
-  }
-  _dartSourcePathsAddedInPreviousCall = [];
-
-  dartSourcesByAbsolutePath.forEach((absolutePath, source) {
-    _dartSourcePathsAddedInPreviousCall.add(absolutePath);
-    _sharedResourceProvider.setOverlay(
-      absolutePath,
-      content: source,
-      modificationStamp: 0,
-    );
-  });
-
-  final results = <String, ResolvedUnitResult>{};
-  for (final path in dartSourcesByPath.keys) {
-    final absolutePath = transformPath(path);
-    final context = _sharedCollection.contextFor(absolutePath);
-    final result = await context.currentSession.getResolvedUnit(absolutePath) as ResolvedUnitResult;
-    final lineInfo = result.lineInfo;
-    final filteredErrors =
-        filterIgnoresForErrors(result.errors, lineInfo, () => IgnoreInfo.forDart(result.unit, result.content))
-            // only fail for error severity errors.
-            .where((error) => error.severity == Severity.error);
-    if (filteredErrors.isNotEmpty) {
-      final source = dartSourcesByPath[path];
-      throw ArgumentError('Parse errors in source "$path":\n${filteredErrors.join('\n')}\nFull source:\n$source');
-    }
-    results[path] = result;
+Future<ResolvedUnitResult> parseAndGetResolvedUnit(String dartSource, {String? path}) async {
+  final sharedContext = SharedAnalysisContext.overReact;
+  final testFilePath = SharedAnalysisContext.overReact.createTestFile(dartSource, filename: path);
+  final result = await sharedContext.collection.contextFor(testFilePath).currentSession.getResolvedUnit(testFilePath)
+      as ResolvedUnitResult;
+
+  final lineInfo = result.lineInfo;
+  final filteredErrors =
+      filterIgnoresForErrors(result.errors, lineInfo, () => IgnoreInfo.forDart(result.unit, result.content))
+          // only fail for error severity errors.
+          .where((error) => error.severity == Severity.error);
+  if (filteredErrors.isNotEmpty) {
+    throw ArgumentError('Parse errors in source "$path":\n${filteredErrors.join('\n')}\nFull source:\n$dartSource');
   }
-  return results;
+  return result;
 }
 
-
 /// Returns [expression] parsed as AST.
 ///
 /// This is accomplished it by including the [expression] as a statement within a wrapper function
@@ -245,15 +120,3 @@ Future<Expression> parseExpression(
   // Unwrap the expression. Don't use `.unparenthesized` since it unwraps all sets of parentheses.
   return (statement.expression as ParenthesizedExpression).expression;
 }
-
-extension<E> on List<E> {
-  E removeSingleWhere(bool Function(E) test) {
-    final firstIndex = indexWhere(test);
-    if (firstIndex == -1) throw StateError('No matching item found');
-
-    final lastIndex = lastIndexWhere(test);
-    if (lastIndex != firstIndex) throw StateError('More than one matching item found');
-
-    return removeAt(firstIndex);
-  }
-}
diff --git a/tools/analyzer_plugin/test/unit/util/analyzer_util_test.dart b/tools/analyzer_plugin/test/unit/util/analyzer_util_test.dart
index 46bd6f94f..ff586e60d 100644
--- a/tools/analyzer_plugin/test/unit/util/analyzer_util_test.dart
+++ b/tools/analyzer_plugin/test/unit/util/analyzer_util_test.dart
@@ -1,4 +1,5 @@
-// Adapted from: https://github.com/dart-lang/sdk/blob/1601f6fcd2a7aa39bdd71f1f988fe7acfaecc418/pkg/analyzer/test/src/dart/ast/utilities_test.dart
+// Adapted from analyzer 5.13.0 src/dart/ast/utilities.dart
+// Permalink: https://github.com/dart-lang/sdk/blob/efe0ca193f1c1485efc5467fb8dc9dfca6085d39/pkg/analyzer/test/src/dart/ast/utilities_test.dart
 //
 // Copyright 2013, the Dart project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
@@ -42,51 +43,66 @@ void main() {
 }
 
 @reflectiveTest
-class NodeLocator2Test {
+class NodeLocator2Test extends _SharedNodeLocatorTests {
+  @override
+  AstNode? locate(
+    CompilationUnit unit,
+    int start, [
+    int? end,
+  ]) {
+    final locator = NodeLocator2(start, end);
+    final node = locator.searchWithin(unit)!;
+    return node;
+  }
+
   void test_onlyStartOffset() {
-    const code = ' int vv; ';
-    //             012345678
+    var code = ' f() {} ';
+    //             01234567
     final unit = parseAndGetUnit(code);
-    final declaration = unit.declarations[0] as TopLevelVariableDeclaration;
-    final variableList = declaration.variables;
-    final typeName = (variableList.type as NamedType).name;
-    final varName = variableList.variables[0].name;
+    final function = unit.declarations.single as FunctionDeclaration;
+    final expression = function.functionExpression;
+    final body = expression.body as BlockFunctionBody;
     expect(NodeLocator2(0).searchWithin(unit), same(unit));
-    expect(NodeLocator2(1).searchWithin(unit), same(typeName));
-    expect(NodeLocator2(2).searchWithin(unit), same(typeName));
-    expect(NodeLocator2(3).searchWithin(unit), same(typeName));
-    expect(NodeLocator2(4).searchWithin(unit), same(variableList));
-    expect(NodeLocator2(5).searchWithin(unit), same(varName));
-    expect(NodeLocator2(6).searchWithin(unit), same(varName));
-    expect(NodeLocator2(7).searchWithin(unit), same(declaration));
-    expect(NodeLocator2(8).searchWithin(unit), same(unit));
-    expect(NodeLocator2(9).searchWithin(unit), isNull);
+    expect(NodeLocator2(1).searchWithin(unit), same(function));
+    expect(NodeLocator2(2).searchWithin(unit), same(function));
+    expect(NodeLocator2(3).searchWithin(unit), same(expression.parameters));
+    expect(NodeLocator2(4).searchWithin(unit), same(expression));
+    expect(NodeLocator2(5).searchWithin(unit), same(body.block));
+    expect(NodeLocator2(6).searchWithin(unit), same(body.block));
+    expect(NodeLocator2(7).searchWithin(unit), same(unit));
     expect(NodeLocator2(100).searchWithin(unit), isNull);
   }
 
   void test_startEndOffset() {
-    const code = ' int vv; ';
-    //             012345678
+    var code = ' f() {} ';
+    //             01234567
     final unit = parseAndGetUnit(code);
-    final declaration = unit.declarations[0] as TopLevelVariableDeclaration;
-    final variableList = declaration.variables;
-    final typeName = (variableList.type as NamedType).name;
-    final varName = variableList.variables[0].name;
+    final function = unit.declarations.single as FunctionDeclaration;
     expect(NodeLocator2(-1, 2).searchWithin(unit), isNull);
     expect(NodeLocator2(0, 2).searchWithin(unit), same(unit));
-    expect(NodeLocator2(1, 2).searchWithin(unit), same(typeName));
-    expect(NodeLocator2(1, 3).searchWithin(unit), same(typeName));
-    expect(NodeLocator2(1, 4).searchWithin(unit), same(variableList));
-    expect(NodeLocator2(5, 6).searchWithin(unit), same(varName));
-    expect(NodeLocator2(5, 7).searchWithin(unit), same(declaration));
-    expect(NodeLocator2(5, 8).searchWithin(unit), same(unit));
+    expect(NodeLocator2(1, 2).searchWithin(unit), same(function));
+    expect(NodeLocator2(1, 3).searchWithin(unit), same(function));
+    expect(NodeLocator2(1, 4).searchWithin(unit), same(function));
+    expect(NodeLocator2(5, 7).searchWithin(unit), same(unit));
     expect(NodeLocator2(5, 100).searchWithin(unit), isNull);
     expect(NodeLocator2(100, 200).searchWithin(unit), isNull);
   }
 }
 
 @reflectiveTest
-class NodeLocatorTest {
+class NodeLocatorTest extends _SharedNodeLocatorTests {
+  @override
+  AstNode? locate(
+    CompilationUnit unit,
+    int start, [
+    int? end,
+  ]) {
+    final locator = NodeLocator(start, end);
+    final node = locator.searchWithin(unit)!;
+    expect(locator.foundNode, same(node));
+    return node;
+  }
+
   void test_range() {
     final unit = parseAndGetUnit("library myLib;");
     final node = _assertLocate(unit, 4, 10);
@@ -121,17 +137,97 @@ class B {}''');
     final node = locator.searchWithin(unit.declarations[1]);
     expect(node, isNull);
   }
+}
+
+abstract class _SharedNodeLocatorTests {
+  AstNode? locate(
+    CompilationUnit unit,
+    int start, [
+    int? end,
+  ]);
+
+  void test_searchWithin_constructor_afterName_beforeParameters() {
+    var source = r'''
+class A {
+  A() {}
+}
+''';
+    var unit = parseAndGetUnit(source);
+    // TODO(dantup): Update these tests to use markers.
+    final node = _assertLocate(unit, source.indexOf('() {}'));
+    expect(node, isA<ConstructorDeclaration>());
+  }
+
+  void test_searchWithin_function_afterName_beforeParameters() {
+    var source = r'''
+void f() {}
+''';
+    var unit = parseAndGetUnit(source);
+    final node = _assertLocate(unit, source.indexOf('() {}'));
+    expect(node, isA<FunctionDeclaration>());
+  }
+
+  void test_searchWithin_function_afterName_beforeTypeParameters() {
+    var source = r'''
+void f<T>() {}
+''';
+    var unit = parseAndGetUnit(source);
+    final node = _assertLocate(unit, source.indexOf('<T>() {}'));
+    expect(node, isA<FunctionDeclaration>());
+  }
+
+  void test_searchWithin_method_afterName_beforeParameters() {
+    var source = r'''
+class A {
+  void m() {}
+}
+''';
+    var unit = parseAndGetUnit(source);
+    final node = _assertLocate(unit, source.indexOf('() {}'));
+    expect(node, isA<MethodDeclaration>());
+  }
+
+  void test_searchWithin_method_afterName_beforeTypeParameters() {
+    var source = r'''
+class A {
+  void m<T>() {}
+}
+''';
+    var unit = parseAndGetUnit(source);
+    final node = _assertLocate(unit, source.indexOf('<T>() {}'));
+    expect(node, isA<MethodDeclaration>());
+  }
+
+  void test_searchWithin_namedConstructor_afterName_beforeParameters() {
+    var source = r'''
+class A {
+  A.c() {}
+}
+''';
+    var unit = parseAndGetUnit(source);
+    final node = _assertLocate(unit, source.indexOf('() {}'));
+    expect(node, isA<ConstructorDeclaration>());
+  }
+
+  void test_searchWithin_setter_afterName_beforeParameters() {
+    var source = r'''
+set s(int i) {}
+''';
+    var unit = parseAndGetUnit(source);
+    final node = _assertLocate(unit, source.indexOf('(int i)'));
+    expect(node, isA<FunctionDeclaration>());
+  }
 
   AstNode _assertLocate(
     CompilationUnit unit,
-    int start,
-    int end,
-  ) {
-    final locator = NodeLocator(start, end);
-    final node = locator.searchWithin(unit)!;
-    expect(locator.foundNode, same(node));
+    int start, [
+    int? end,
+  ]) {
+    end ??= start;
+    final node = locate(unit, start, end)!;
     expect(node.offset <= start, isTrue, reason: "Node starts after range");
-    expect(node.offset + node.length > end, isTrue, reason: "Node ends before range");
+    expect(node.offset + node.length > end, isTrue,
+        reason: "Node ends before range");
     return node;
   }
 }
diff --git a/tools/analyzer_plugin/test/unit/util/ast_util_test.dart b/tools/analyzer_plugin/test/unit/util/ast_util_test.dart
index 07b698611..9e3494d87 100644
--- a/tools/analyzer_plugin/test/unit/util/ast_util_test.dart
+++ b/tools/analyzer_plugin/test/unit/util/ast_util_test.dart
@@ -9,14 +9,17 @@ void main() {
   group('ast_util', () {
     test('allDescendants returns all descendants in breadth-first order', () {
       final unit = parseAndGetUnit(/*language=dart*/ r'''
-        class A {}
+        class A {
+          var field;
+        }
         class B {}
       ''');
       expect(allDescendants(unit), [
         isA<ClassDeclaration>(), // class A {}
         isA<ClassDeclaration>(), // class B {}
-        isA<Identifier>(), // A
-        isA<Identifier>(), // B
+        isA<FieldDeclaration>(), // var field;
+        isA<VariableDeclarationList>(), // field
+        isA<VariableDeclaration>(), // field
       ]);
     });
 
@@ -81,7 +84,7 @@ void main() {
           final usage = getAllPrintedExpressions(unit).single as Identifier;
           expect(usage.name, 'foo', reason: 'test setup check');
           expect(usage.staticElement, isNotNull, reason: 'test setup check');
-          expect(lookUpVariable(usage.staticElement!, unit)?.name.name, 'foo');
+          expect(lookUpVariable(usage.staticElement!, unit)?.name.lexeme, 'foo');
         });
 
         group('returns null when', () {
@@ -180,7 +183,7 @@ void main() {
           final usage = getAllPrintedExpressions(unit).single as Identifier;
           expect(usage.name, 'foo', reason: 'test setup check');
           expect(usage.staticElement, isNotNull, reason: 'test setup check');
-          expect((lookUpDeclaration(usage.staticElement!, unit) as FunctionDeclaration).name.name, 'foo');
+          expect((lookUpDeclaration(usage.staticElement!, unit) as FunctionDeclaration).name.lexeme, 'foo');
         });
 
         test('looks up a variable', () async {
@@ -193,7 +196,7 @@ void main() {
           final usage = getAllPrintedExpressions(unit).single as Identifier;
           expect(usage.name, 'foo', reason: 'test setup check');
           expect(usage.staticElement, isNotNull, reason: 'test setup check');
-          expect((lookUpDeclaration(usage.staticElement!, unit) as VariableDeclaration).name.name, 'foo');
+          expect((lookUpDeclaration(usage.staticElement!, unit) as VariableDeclaration).name.lexeme, 'foo');
         });
 
         test('looks up a class', () async {
@@ -207,7 +210,7 @@ void main() {
           final usage = getAllPrintedExpressions(unit).single as Identifier;
           expect(usage.name, 'Foo', reason: 'test setup check');
           expect(usage.staticElement, isNotNull, reason: 'test setup check');
-          expect((lookUpDeclaration(usage.staticElement!, unit) as ClassDeclaration).name.name, 'Foo');
+          expect((lookUpDeclaration(usage.staticElement!, unit) as ClassDeclaration).name.lexeme, 'Foo');
         });
 
         group('returns null when', () {
@@ -245,7 +248,7 @@ void main() {
           final usage = getAllPrintedExpressions(unit).single as Identifier;
           expect(usage.name, 'foo', reason: 'test setup check');
           expect(usage.staticElement, isNotNull, reason: 'test setup check');
-          expect(lookUpParameter(usage.staticElement!, unit)?.identifier?.name, 'foo');
+          expect(lookUpParameter(usage.staticElement!, unit)?.name?.lexeme, 'foo');
         });
 
         test('looks up a named parameter', () async {
@@ -257,7 +260,7 @@ void main() {
           final usage = getAllPrintedExpressions(unit).single as Identifier;
           expect(usage.name, 'foo', reason: 'test setup check');
           expect(usage.staticElement, isNotNull, reason: 'test setup check');
-          expect(lookUpParameter(usage.staticElement!, unit)?.identifier?.name, 'foo');
+          expect(lookUpParameter(usage.staticElement!, unit)?.name?.lexeme, 'foo');
         });
 
         group('returns null when', () {
diff --git a/tools/analyzer_plugin/test/unit/util/boilerplate_utils_test.dart b/tools/analyzer_plugin/test/unit/util/boilerplate_utils_test.dart
index 659549492..50c16ba0e 100644
--- a/tools/analyzer_plugin/test/unit/util/boilerplate_utils_test.dart
+++ b/tools/analyzer_plugin/test/unit/util/boilerplate_utils_test.dart
@@ -4,6 +4,8 @@
 import 'package:analyzer/dart/analysis/results.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
+import 'package:meta/meta.dart';
+import 'package:path/path.dart' as p;
 import 'package:over_react_analyzer_plugin/src/diagnostic_contributor.dart';
 import 'package:over_react_analyzer_plugin/src/util/ast_util.dart';
 import 'package:over_react_analyzer_plugin/src/util/boilerplate_utils.dart';
@@ -12,59 +14,94 @@ import 'package:test/test.dart';
 
 import '../../test_util.dart';
 
-const sourceWithOverReactPart = /*language=dart*/ r'''
-  import 'package:over_react/over_react.dart';
-
-  // ignore: uri_has_not_been_generated
-  part 'foo.over_react.g.dart';
-  
-  UiFactory<FooProps> Foo = _$Foo; // ignore: undefined_identifier, invalid_assignment
-  
-  mixin FooProps on UiProps {}
-  
-  class FooComponent extends UiComponent2<FooProps> {
-    @override
-    void render() {}
-  }
-''';
-
-const sourceWithNonOverReactPart = /*language=dart*/ r'''
-  import 'package:over_react/over_react.dart';
-
-  // ignore: uri_has_not_been_generated
-  part 'foo.not_over_react.g.dart';
-  
-  UiFactory<FooProps> Foo = _$Foo; // ignore: undefined_identifier, invalid_assignment
-  
-  mixin FooProps on UiProps {}
-  
-  class FooComponent extends UiComponent2<FooProps> {
-    @override
-    void render() {}
-  }
-''';
-
-const sourceWithNoPart = /*language=dart*/ r'''
-  import 'package:over_react/over_react.dart';
-
-  UiFactory<FooProps> Foo = _$Foo; // ignore: undefined_identifier, invalid_assignment
-
-  mixin FooProps on UiProps {}
-
-  class FooComponent extends UiComponent2<FooProps> {
-    @override
-    void render() {}
-  }
-''';
+String basenameWithoutExtensionOrSuffixes(String filenameOrPath) =>
+    p.basenameWithoutExtension(filenameOrPath).split('.').first;
 
 void main() {
   group('boilerplate_util', () {
+    // Use different names each time so they don't conflict in the SharedAnalysisContext.
+    // Usually we don't have to worry about this since names are auto-generated, but
+    // these tests involve need to explicit specifying names to properly test part handling.
+    var nameCounter = 0;
+    String testName;
+    String testDifferentName;
+
+    String sourceWithOverReactPart;
+    String sourceWithNonOverReactPart;
+    String sourceWithNoPart;
+
+    setUp(() {
+      nameCounter++;
+      testName = 'test_name_$nameCounter';
+      testDifferentName = 'test_different_name_$nameCounter';
+
+      sourceWithOverReactPart = '''
+        import 'package:over_react/over_react.dart';
+      
+        // ignore: uri_has_not_been_generated
+        part '$testName.over_react.g.dart';
+        
+        UiFactory<FooProps> Foo = _\$Foo; // ignore: undefined_identifier, invalid_assignment
+        
+        mixin FooProps on UiProps {}
+        
+        class FooComponent extends UiComponent2<FooProps> {
+          @override
+          void render() {}
+        }
+      ''';
+
+      sourceWithNonOverReactPart = '''
+        import 'package:over_react/over_react.dart';
+      
+        // ignore: uri_has_not_been_generated
+        part '$testName.not_over_react.g.dart';
+        
+        UiFactory<FooProps> Foo = _\$Foo; // ignore: undefined_identifier, invalid_assignment
+        
+        mixin FooProps on UiProps {}
+        
+        class FooComponent extends UiComponent2<FooProps> {
+          @override
+          void render() {}
+        }
+      ''';
+
+      sourceWithNoPart = '''
+        import 'package:over_react/over_react.dart';
+      
+        UiFactory<FooProps> Foo = _\$Foo; // ignore: undefined_identifier, invalid_assignment
+      
+        mixin FooProps on UiProps {}
+      
+        class FooComponent extends UiComponent2<FooProps> {
+          @override
+          void render() {}
+        }
+      ''';
+    });
+
+    Future<void> checkPartValidity({
+      bool shouldBeValid = true,
+      bool isPartOverReact = true,
+      @required String path,
+    }) async {
+      final result = await parseAndGetResolvedUnit(
+        isPartOverReact ? sourceWithOverReactPart : sourceWithNonOverReactPart,
+        path: path,
+      );
+      final part = result.unit.directives.whereType<PartDirective>().firstOrNull;
+      expect(part, isNotNull);
+      expect(result.uri.path, endsWith('/$path'));
+      expect(overReactGeneratedPartDirectiveIsValid(part, result.uri), shouldBeValid);
+    }
+
     group('getOverReactGeneratedPartDirective', () {
       test('returns correct over_react part directive', () {
         final unit = parseAndGetUnit(sourceWithOverReactPart);
         final result = getOverReactGeneratedPartDirective(unit);
         expect(result, isA<PartDirective>());
-        expect(result.uri.stringValue, 'foo.over_react.g.dart');
+        expect(result.uri.stringValue, '$testName.over_react.g.dart');
       });
 
       group('returns null when', () {
@@ -82,12 +119,13 @@ void main() {
 
     group('overReactGeneratedPartDirectiveIsValid', () {
       test('returns true when valid part directive matches the file uri', () async {
-        await checkPartValidity();
+        await checkPartValidity(path: '$testName.dart');
       });
 
       group('returns false when', () {
         test('part directive is not over_react', () async {
           await checkPartValidity(
+            path: '$testName.dart',
             isPartOverReact: false,
             shouldBeValid: false,
           );
@@ -95,7 +133,7 @@ void main() {
 
         test('part directive does not match the file uri', () async {
           await checkPartValidity(
-            path: 'different_file_path.dart',
+            path: '$testDifferentName.dart',
             shouldBeValid: false,
           );
         });
@@ -107,14 +145,14 @@ void main() {
         final sourceFileEdits = await getSourceFileEdits(
           sourceWithOverReactPart,
           (builder, result) => addOverReactGeneratedPartDirective(builder, result.unit, result.lineInfo, result.uri),
-          path: 'foo.dart',
+          path: '$testName.dart',
         );
         expect(sourceFileEdits, isEmpty);
       });
 
       group('adds a valid part directive', () {
         test('when there are no part directives in the file', () async {
-          final result = await parseAndGetResolvedUnit(sourceWithNoPart, path: 'foo.dart');
+          final result = await parseAndGetResolvedUnit(sourceWithNoPart, path: '$testName.dart');
           final sourceChange = await buildFileEdit(result, (builder) {
             addOverReactGeneratedPartDirective(builder, result.unit, result.lineInfo, result.uri);
           });
@@ -127,11 +165,11 @@ void main() {
               result.lineInfo.getOffsetOfLineAfter(nextLine(result.unit.directives.last.end, result.lineInfo));
           expect(editList.first.offset, offset, reason: 'should be new line between existing directives and new part');
           expect(editList.first.length, 0, reason: 'nothing is replaced');
-          expect(editList.first.replacement, 'part \'foo.over_react.g.dart\';\n\n');
+          expect(editList.first.replacement, 'part \'$testName.over_react.g.dart\';\n\n');
         });
 
         test('when there is an existing part directive in the file', () async {
-          final result = await parseAndGetResolvedUnit(sourceWithNonOverReactPart, path: 'foo.dart');
+          final result = await parseAndGetResolvedUnit(sourceWithNonOverReactPart, path: '$testName.dart');
           final sourceChange = await buildFileEdit(result, (builder) {
             addOverReactGeneratedPartDirective(builder, result.unit, result.lineInfo, result.uri);
           });
@@ -143,7 +181,7 @@ void main() {
           final offset = result.lineInfo.getOffsetOfLineAfter(result.unit.directives.last.end);
           expect(editList.first.offset, offset, reason: 'new part should be on the line after existing part');
           expect(editList.first.length, 0, reason: 'nothing is replaced');
-          expect(editList.first.replacement, 'part \'foo.over_react.g.dart\';\n\n');
+          expect(editList.first.replacement, 'part \'$testName.over_react.g.dart\';\n\n');
         });
       });
 
@@ -170,7 +208,7 @@ void main() {
           final sourceFileEdits = await getSourceFileEdits(
             sourceWithNoPart,
             (builder, result) => removeOverReactGeneratedPartDirective(builder, result.unit),
-            path: 'foo.dart',
+            path: '$testName.dart',
           );
           expect(sourceFileEdits, isEmpty);
         });
@@ -179,7 +217,7 @@ void main() {
           final sourceFileEdits = await getSourceFileEdits(
             sourceWithNonOverReactPart,
             (builder, result) => removeOverReactGeneratedPartDirective(builder, result.unit),
-            path: 'foo.dart',
+            path: '$testName.dart',
           );
           expect(sourceFileEdits, isEmpty);
         });
@@ -187,7 +225,7 @@ void main() {
 
       group('removes over_react part directive if it exists', () {
         test('', () async {
-          final result = await parseAndGetResolvedUnit(sourceWithOverReactPart, path: 'foo.dart');
+          final result = await parseAndGetResolvedUnit(sourceWithOverReactPart, path: '$testName.dart');
           final sourceChange = await buildFileEdit(result, (builder) {
             removeOverReactGeneratedPartDirective(builder, result.unit);
           });
@@ -203,17 +241,17 @@ void main() {
         });
 
         test('and there are other part directives in file', () async {
-          final result = await parseAndGetResolvedUnit(/*language=dart*/ r'''
+          final result = await parseAndGetResolvedUnit('''
             import 'package:over_react/over_react.dart';
           
             // ignore: uri_has_not_been_generated
-            part 'foo.not_over_react.g.dart';
+            part '$testName.not_over_react.g.dart';
             // ignore: uri_has_not_been_generated
-            part 'foo.over_react.g.dart';
+            part '$testName.over_react.g.dart';
             // ignore: uri_has_not_been_generated
             part 'other.not_over_react.g.dart';
             
-            UiFactory<FooProps> Foo = _$Foo; // ignore: undefined_identifier, invalid_assignment
+            UiFactory<FooProps> Foo = _\$Foo; // ignore: undefined_identifier, invalid_assignment
             
             mixin FooProps on UiProps {}
             
@@ -221,7 +259,7 @@ void main() {
               @override
               void render() {}
             }
-          ''', path: 'foo.dart');
+          ''', path: '$testName.dart');
           final sourceChange = await buildFileEdit(result, (builder) {
             removeOverReactGeneratedPartDirective(builder, result.unit);
           });
@@ -244,7 +282,7 @@ void main() {
           final sourceFileEdits = await getSourceFileEdits(
             sourceWithNoPart,
             (builder, result) => fixOverReactGeneratedPartDirective(builder, result.unit, result.uri),
-            path: 'foo.dart',
+            path: '$testName.dart',
           );
           expect(sourceFileEdits, isEmpty);
         });
@@ -253,7 +291,7 @@ void main() {
           final sourceFileEdits = await getSourceFileEdits(
             sourceWithOverReactPart,
             (builder, result) => fixOverReactGeneratedPartDirective(builder, result.unit, result.uri),
-            path: 'foo.dart',
+            path: '$testName.dart',
           );
           expect(sourceFileEdits, isEmpty);
         });
@@ -262,14 +300,14 @@ void main() {
           final sourceFileEdits = await getSourceFileEdits(
             sourceWithNonOverReactPart,
             (builder, result) => fixOverReactGeneratedPartDirective(builder, result.unit, result.uri),
-            path: 'foo.dart',
+            path: '$testName.dart',
           );
           expect(sourceFileEdits, isEmpty);
         });
       });
 
       test('replaces over_react part directive that does not match file uri', () async {
-        final result = await parseAndGetResolvedUnit(sourceWithOverReactPart, path: 'different_file_name.dart');
+        final result = await parseAndGetResolvedUnit(sourceWithOverReactPart, path: '$testDifferentName.dart');
         final sourceChange = await buildFileEdit(result, (builder) {
           fixOverReactGeneratedPartDirective(builder, result.unit, result.uri);
         });
@@ -281,31 +319,17 @@ void main() {
         final part = getOverReactGeneratedPartDirective(result.unit);
         expect(editList.first.offset, part.offset);
         expect(editList.first.length, part.length);
-        expect(editList.first.replacement, 'part \'different_file_name.over_react.g.dart\';');
+        expect(editList.first.replacement, 'part \'$testDifferentName.over_react.g.dart\';');
       });
     });
   });
 }
 
-Future<void> checkPartValidity({
-  bool shouldBeValid = true,
-  bool isPartOverReact = true,
-  String path = 'foo.dart',
-}) async {
-  final result = await parseAndGetResolvedUnit(
-    isPartOverReact ? sourceWithOverReactPart : sourceWithNonOverReactPart,
-    path: path,
-  );
-  final part = result.unit.directives.whereType<PartDirective>().firstOrNull;
-  expect(part, isNotNull);
-  expect(result.uri.toFilePath(), endsWith('/$path'));
-  expect(overReactGeneratedPartDirectiveIsValid(part, result.uri), shouldBeValid);
-}
 
 Future<List<SourceFileEdit>> getSourceFileEdits(
   String dartSource,
   void Function(DartFileEditBuilder builder, ResolvedUnitResult result) callUtilityFunction, {
-  String path = 'foo.dart',
+  @required String path,
 }) async {
   final result = await parseAndGetResolvedUnit(dartSource, path: path);
   final sourceChange = await buildFileEdit(result, (builder) {
diff --git a/tools/analyzer_plugin/test/unit/util/component_usage_test.dart b/tools/analyzer_plugin/test/unit/util/component_usage_test.dart
index aa484b8ea..3897e1876 100644
--- a/tools/analyzer_plugin/test/unit/util/component_usage_test.dart
+++ b/tools/analyzer_plugin/test/unit/util/component_usage_test.dart
@@ -423,7 +423,7 @@ void main() {
               expect(
                 componentUsage.propsClassElement,
                 builderSource.canBuilderResolve
-                    ? isA<ClassElement>().having((c) => c.name, 'name', builderSource.propsName)
+                    ? isA<InterfaceElement>().having((c) => c.name, 'name', builderSource.propsName)
                     : isNull,
               );
               expect(
diff --git a/tools/analyzer_plugin/test/util/package_util.dart b/tools/analyzer_plugin/test/util/package_util.dart
new file mode 100644
index 000000000..2369f8ce2
--- /dev/null
+++ b/tools/analyzer_plugin/test/util/package_util.dart
@@ -0,0 +1,136 @@
+// From https://github.com/Workiva/over_react_codemod/blob/a14a4ef372a1b2c2a625755cec7a6f956a074650/lib/src/util/package_util.dart
+
+// Copyright 2021 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'dart:io';
+
+import 'package:collection/collection.dart';
+import 'package:logging/logging.dart';
+import 'package:path/path.dart' as p;
+
+final _logger = Logger('orcm.pubspec');
+
+bool _isPubGetNecessary(String packageRoot) {
+  final packageConfig =
+      File(p.join(packageRoot, '.dart_tool', 'package_config.json'));
+  final pubspec = File(p.join(packageRoot, 'pubspec.yaml'));
+  final pubspecLock = File(p.join(packageRoot, 'pubspec.lock'));
+
+  if (!pubspec.existsSync()) {
+    throw ArgumentError('pubspec.yaml not found in directory: $packageRoot');
+  }
+
+  if (packageConfig.existsSync() && pubspecLock.existsSync()) {
+    return !pubspecLock.lastModifiedSync().isAfter(pubspec.lastModifiedSync());
+  }
+
+  return true;
+}
+
+/// Runs `pub get` in [packageRoot] unless running `pub get` would have no effect.
+void runPubGetIfNeeded(String packageRoot) {
+  if (_isPubGetNecessary(packageRoot)) {
+    runPubGet(packageRoot);
+  } else {
+    _logger.info(
+        'Skipping `pub get`, which has already been run, in `$packageRoot`');
+  }
+}
+
+/// Runs `pub get` in [workingDirectory], and throws if the command completed
+/// with a non-zero exit code.
+///
+/// For convenience, tries running with `pub get --offline` if `pub get` fails,
+/// for a better experience when not authenticated to private pub servers.
+void runPubGet(String workingDirectory) {
+  _logger.info('Running `pub get` in `$workingDirectory`...');
+
+  final result = Process.runSync('dart', ['pub', 'get'],
+      workingDirectory: workingDirectory,
+      runInShell: true
+  );
+  final exitCode = result.exitCode;
+
+  if (exitCode == 69) {
+    _logger.info(
+        'Re-running `pub get` but with `--offline`, to hopefully fix the above error.');
+    final retryResult = Process.runSync('pub', ['get', '--offline'],
+        workingDirectory: workingDirectory,
+        runInShell: true);
+    final exitCode = retryResult.exitCode;
+    if (exitCode != 0) {
+      throw Exception('pub get failed with exit code $exitCode in $workingDirectory');
+    }
+  } else if (exitCode != 0) {
+    throw Exception('pub get failed with exit code $exitCode in $workingDirectory');
+  }
+}
+
+/// Returns a path to the closest Dart package root (i.e., a directory with a
+/// pubspec.yaml file) to [path], throwing if no package root can be found.
+///
+/// If [path] is itself a package root, it will be returned.
+///
+/// Example:
+///
+/// ```dart
+/// // All of these return a path to 'some_package'
+/// findPackageRootFor('some_package/lib/src/file.dart');
+/// findPackageRootFor('some_package/lib/');
+/// findPackageRootFor('some_package');
+///
+/// // Returns a path to 'some_package/subpackages/some_nested_package'
+/// findPackageRootFor('some_package/some_nested_package/lib/file.dart');
+/// ```
+String findPackageRootFor(String path) {
+  final packageRoot = [
+    path,
+    ...ancestorsOfPath(path)
+  ].firstWhereOrNull((path) => File(p.join(path, 'pubspec.yaml')).existsSync());
+
+  if (packageRoot == null) {
+    throw Exception('Could not find package root for file `$path`');
+  }
+
+  return packageRoot;
+}
+
+/// Returns canonicalized paths for all the the ancestor directories of [path],
+/// starting with its parent and working upwards.
+Iterable<String> ancestorsOfPath(String path) sync* {
+  path = p.canonicalize(path);
+
+  // p.dirname of the root directory is the root directory, so if they're the same, stop.
+  final parent = p.dirname(path);
+  if (p.equals(path, parent)) return;
+
+  yield parent;
+  yield* ancestorsOfPath(parent);
+}
+
+/// Returns whether [file] is within a top-level `build` directory of a package root.
+bool isNotWithinTopLevelBuildOutputDir(File file) =>
+    !isWithinTopLevelDir(file, 'build');
+
+/// Returns whether [file] is within a top-level `tool` directory of a package root.
+bool isNotWithinTopLevelToolDir(File file) =>
+    !isWithinTopLevelDir(file, 'tool');
+
+/// Returns whether [file] is within a top-level [topLevelDir] directory
+/// (e.g., `bin`, `lib`, `web`) of a package root.
+bool isWithinTopLevelDir(File file, String topLevelDir) =>
+    ancestorsOfPath(file.path).any((ancestor) =>
+        p.basename(ancestor) == topLevelDir &&
+        File(p.join(p.dirname(ancestor), 'pubspec.yaml')).existsSync());
diff --git a/tools/analyzer_plugin/test/util/package_util_test.dart b/tools/analyzer_plugin/test/util/package_util_test.dart
new file mode 100644
index 000000000..c53ef8948
--- /dev/null
+++ b/tools/analyzer_plugin/test/util/package_util_test.dart
@@ -0,0 +1,223 @@
+// From https://github.com/Workiva/over_react_codemod/blob/a14a4ef372a1b2c2a625755cec7a6f956a074650/test/util/package_util_test.dart
+//
+// Copyright 2021 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'dart:io';
+
+
+import 'package:path/path.dart' as p;
+import 'package:test/test.dart';
+
+import './package_util.dart';
+
+void main() {
+  group('Package Utilities', () {
+    // Use a utility to determine the path to the root directory since it will
+    // be different when run locally or in CI.
+    final currentPathFromRoot = p.canonicalize('.');
+
+    group('findPackageRootFor', () {
+      test('on the current directory', () {
+        expect(findPackageRootFor('.'), equals('.'));
+      });
+
+      test('on a nested file', () {
+        expect(
+          findPackageRootFor('./test/util/package_util_test.dart'),
+          equals(currentPathFromRoot),
+        );
+      });
+
+      test('with a nested pubspec', () {
+        expect(
+          findPackageRootFor(
+              'test/test_fixtures/over_react_project/lib/analysis_warmup.dart'),
+          equals('$currentPathFromRoot/test/test_fixtures/over_react_project'),
+        );
+      });
+
+      test('on a pubspec file', () {
+        expect(
+          findPackageRootFor('$currentPathFromRoot/pubspec.yaml'),
+          equals(currentPathFromRoot),
+        );
+      });
+
+      test('when a pubspec cannot be found', () {
+        final tmpDir = Directory.systemTemp.createTempSync();
+        addTearDown(tmpDir.deleteSync);
+        expect(
+          () => findPackageRootFor(tmpDir.path),
+          throwsA(isA<Exception>()
+              .havingToStringValue(contains('Could not find package root'))),
+        );
+      });
+    });
+
+    group('ancestorsOfPath', () {
+      final ancestorsOfPathFromRoot = <String>[];
+
+      setUpAll(() {
+        // Determine the expected ancestors of the current path from root.
+        final segments = p.split(currentPathFromRoot);
+        for (var i = 1; i < segments.length; i++) {
+          ancestorsOfPathFromRoot
+              .add(p.joinAll(segments.sublist(0, segments.length - i)));
+        }
+      });
+
+      test('for a nested file', () {
+        expect(
+          ancestorsOfPath(
+              'test/test_fixtures/over_react_project/lib/analysis_warmup.dart'),
+          orderedEquals(<String>[
+            '$currentPathFromRoot/test/test_fixtures/over_react_project/lib',
+            '$currentPathFromRoot/test/test_fixtures/over_react_project',
+            '$currentPathFromRoot/test/test_fixtures',
+            '$currentPathFromRoot/test',
+            currentPathFromRoot,
+            ...ancestorsOfPathFromRoot,
+          ]),
+        );
+      });
+
+      test('for a nested directory', () {
+        expect(
+          ancestorsOfPath('lib/src/util'),
+          orderedEquals(<String>[
+            '$currentPathFromRoot/lib/src',
+            '$currentPathFromRoot/lib',
+            currentPathFromRoot,
+            ...ancestorsOfPathFromRoot,
+          ]),
+        );
+      });
+
+      test('on the current directory', () {
+        expect(
+          ancestorsOfPath('.'),
+          orderedEquals(ancestorsOfPathFromRoot),
+        );
+      });
+    });
+
+    group('top-level directory checking utilities', () {
+      List<File>? filesInTopLevelDir;
+      List<File>? filesNotInTopLevelBuildDir;
+
+      // Set the top level directory that the test cases use for verifying output.
+      void _initializeTestCases(String directory) {
+        filesInTopLevelDir = [
+          File('$directory/some_place/some_file.dart'),
+          File(
+              'test/test_fixtures/over_react_project/$directory/lib/analysis_warmup.dart'),
+        ];
+        filesNotInTopLevelBuildDir = [
+          File('test/$directory/some_place/some_file.dart'),
+          File('some_file.dart'),
+          File(
+              'test/test_fixtures/$directory/over_react_project/lib/analysis_warmup.dart'),
+          File(
+              'test/test_fixtures/over_react_project/lib/$directory/analysis_warmup.dart'),
+        ];
+      }
+
+      tearDown(() {
+        filesInTopLevelDir = null;
+        filesNotInTopLevelBuildDir = null;
+      });
+
+      group('isWithinTopLevelDir', () {
+        const testDirectory = 'some_directory';
+
+        test('for files in top-level dir input', () {
+          _initializeTestCases(testDirectory);
+          for (final file in filesInTopLevelDir!) {
+            expect(
+              isWithinTopLevelDir(file, testDirectory),
+              isTrue,
+              reason: '${file.path} is in a top-level $testDirectory directory',
+            );
+          }
+        });
+
+        test('for files not in top-level dir input', () {
+          _initializeTestCases(testDirectory);
+          for (final file in filesNotInTopLevelBuildDir!) {
+            expect(
+              isWithinTopLevelDir(file, testDirectory),
+              isFalse,
+              reason:
+                  '${file.path} is not in a top-level $testDirectory directory',
+            );
+          }
+        });
+      });
+
+      group('isNotWithinTopLevelBuildOutputDir', () {
+        test('for files in top-level build dir', () {
+          _initializeTestCases('build');
+          for (final file in filesInTopLevelDir!) {
+            expect(
+              isNotWithinTopLevelBuildOutputDir(file),
+              isFalse,
+              reason: '${file.path} is in a top-level build directory',
+            );
+          }
+        });
+
+        test('for files not in top-level build dir', () {
+          _initializeTestCases('build');
+          for (final file in filesNotInTopLevelBuildDir!) {
+            expect(
+              isNotWithinTopLevelBuildOutputDir(file),
+              isTrue,
+              reason: '${file.path} is not in a top-level build directory',
+            );
+          }
+        });
+      });
+
+      group('isNotWithinTopLevelToolDir', () {
+        test('for files in top-level tool dir', () {
+          _initializeTestCases('tool');
+          for (final file in filesInTopLevelDir!) {
+            expect(
+              isNotWithinTopLevelToolDir(file),
+              isFalse,
+              reason: '${file.path} is in a top-level tool directory',
+            );
+          }
+        });
+
+        test('for files not in top-level tool dir', () {
+          _initializeTestCases('tool');
+          for (final file in filesNotInTopLevelBuildDir!) {
+            expect(
+              isNotWithinTopLevelToolDir(file),
+              isTrue,
+              reason: '${file.path} is not in a top-level tool directory',
+            );
+          }
+        });
+      });
+    });
+  });
+}
+
+extension ObjectMatchers on TypeMatcher<Object> {
+  Matcher havingToStringValue(dynamic matcher) =>
+      having((p) => p.toString(), 'toString() value', matcher);
+}
diff --git a/tools/analyzer_plugin/test/util/shared_analysis_context.dart b/tools/analyzer_plugin/test/util/shared_analysis_context.dart
new file mode 100644
index 000000000..dfd5a1cb6
--- /dev/null
+++ b/tools/analyzer_plugin/test/util/shared_analysis_context.dart
@@ -0,0 +1,290 @@
+// From https://github.com/Workiva/over_react_codemod/blob/a14a4ef372a1b2c2a625755cec7a6f956a074650/test/resolved_file_context.dart
+
+// ignore_for_file: comment_references
+
+// Copyright 2021 Workiva Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+import 'dart:async';
+import 'dart:io';
+
+import 'package:analyzer/dart/analysis/analysis_context_collection.dart';
+import 'package:analyzer/dart/analysis/results.dart';
+import 'package:analyzer/diagnostic/diagnostic.dart';
+import 'package:analyzer/error/error.dart';
+import 'package:io/io.dart';
+import 'package:path/path.dart' as p;
+import 'package:uuid/uuid.dart';
+
+import 'package_util.dart';
+import 'util.dart';
+
+/// Provides a mechanism for getting resolved codemod [TestFile]s for test cases
+/// using a shared context root, allowing:
+///
+/// - the resolution of package imports (provided they're depended on in the context root's pubspec.yaml)
+/// - multiple tests to run without `pub get`-ing in a new package or spinning up
+///   a new same [AnalysisContextCollection], which dramatically improves test run times
+///   if there are many tests that rely on a resolved context.
+///
+/// Also, re-using a fixed directory instead of a new temporary directory each time
+/// means that `pub get`s from the previous run as well as any analysis cached
+/// within `~/.dartServer` can be reused between test runs, which means faster
+/// test runs during local development.
+class SharedAnalysisContext {
+  /// A context root located at `test/test_fixtures/over_react_project`
+  /// that depends on the `over_react` package.
+  static final overReact =
+      SharedAnalysisContext(p.join(findPackageRootFor(p.current), 'test/test_fixtures/over_react_project'));
+
+  /// Creates a temporary copy of the files in this context.
+  ///
+  /// Useful when you want mostly the same setup as an existing context,
+  /// but need additional changes to pubspec.yaml or analysis_options.yaml.
+  static SharedAnalysisContext createTemporaryCopy(SharedAnalysisContext other, String newParentDirectory) {
+    final copyParentDir = Directory(p.join(findPackageRootFor(p.current), newParentDirectory));
+    copyParentDir.createSync(recursive: true);
+    final copyDir = copyParentDir.createTempSync().path;
+    // Adapted from package:io 1.0.4 `copyPathSync`.
+    // Permalink https://github.com/dart-lang/io/blob/0c6fa36867b64748639515d5ea37b99176772756/lib/src/copy_path.dart#L54
+    //
+    // Copyright 2017, the Dart project authors.
+    //
+    // Redistribution and use in source and binary forms, with or without
+    // modification, are permitted provided that the following conditions are
+    // met:
+    //
+    //     * Redistributions of source code must retain the above copyright
+    //       notice, this list of conditions and the following disclaimer.
+    //     * Redistributions in binary form must reproduce the above
+    //       copyright notice, this list of conditions and the following
+    //       disclaimer in the documentation and/or other materials provided
+    //       with the distribution.
+    //     * Neither the name of Google LLC nor the names of its
+    //       contributors may be used to endorse or promote products derived
+    //       from this software without specific prior written permission.
+    //
+    // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+    // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+    // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+    // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+    // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+    // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+    // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+    // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+    // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+    // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+    // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+    for (final file in Directory(other.contextRootPath).listSync(recursive: false)) {
+      if (const {'pubspec.lock', '.dart_tool'}.contains(p.basename(file.path))) {
+        continue;
+      }
+
+      final copyTo = p.join(copyDir, p.relative(file.path, from: other.contextRootPath));
+      if (file is Directory) {
+        copyPathSync(file.path, copyTo);
+      } else if (file is File) {
+        File(file.path).copySync(copyTo);
+      } else if (file is Link) {
+        Link(copyTo).createSync(file.targetSync(), recursive: true);
+      }
+    }
+    return SharedAnalysisContext._temporaryCopy(copyDir, customPubGetErrorMessage: other.customPubGetErrorMessage);
+  }
+
+  /// The path to the package root in which test files will be created
+  /// and resolved.
+  final String contextRootPath;
+
+  /// Whether this is a temporary copy of another shared context that should be deleted after use.
+  final bool isTemporaryCopy;
+
+  /// The analysis context collection for files within [contextRootPath], initialized
+  /// lazily.
+  late final AnalysisContextCollection collection = _initCollection();
+
+  /// A custom error message to display if `pub get` fails.
+  final String? customPubGetErrorMessage;
+
+  // Namespace the test path using a UUID so that concurrent runs
+  // don't try to output the same filename, making it so that we can
+  // easily create new filenames by counting synchronously [nextFilename]
+  // without coordinating with other test processes.
+  //
+  // This also allows us to keep using the same project directory among concurrent tests
+  // and across test runs, which means the Dart analysis server can use cached
+  // analysis results (meaning faster test runs).
+  final _testFileSubpath = 'lib/dynamic_test_files/${Uuid().v4()}';
+
+  SharedAnalysisContext._(
+      {required this.contextRootPath, required this.isTemporaryCopy, this.customPubGetErrorMessage}) {
+    if (!p.isAbsolute(contextRootPath)) {
+      throw ArgumentError.value(contextRootPath, 'projectRoot', 'must be absolute');
+    }
+  }
+
+  SharedAnalysisContext._temporaryCopy(String contextRootPath, {String? customPubGetErrorMessage})
+      : this._(
+          contextRootPath: contextRootPath,
+          customPubGetErrorMessage: customPubGetErrorMessage,
+          isTemporaryCopy: true,
+        );
+
+  SharedAnalysisContext(String contextRootPath, {String? customPubGetErrorMessage})
+      : this._(
+          contextRootPath: contextRootPath,
+          customPubGetErrorMessage: customPubGetErrorMessage,
+          isTemporaryCopy: false,
+        );
+
+  AnalysisContextCollection _initCollection() {
+    // Note that if tests are run concurrently, then concurrent pub gets will be run.
+    // This is hard to avoid (trying to avoid it using a filesystem lock in
+    // macOS/Linux doesn't work due to advisory lock behavior), but intermittently
+    // causes issues, so message referencing exit code 66 and workaround below.
+    try {
+      runPubGetIfNeeded(contextRootPath);
+    } catch (e, st) {
+      var message = [
+        // ignore: no_adjacent_strings_in_list
+        'If the exit code is 66, the issue is likely concurrent `pub get`s on'
+            ' this directory from concurrent test entrypoints.'
+            ' Regardless of the exit code, if in CI, try running `pub get`'
+            ' in this directory before running any tests.',
+        if (customPubGetErrorMessage != null) customPubGetErrorMessage,
+      ].join(' ');
+      throw Exception('$message\nOriginal exception: $e$st');
+    }
+
+    return AnalysisContextCollection(
+      includedPaths: [contextRootPath],
+    );
+  }
+
+  /// Warms up the AnalysisContextCollection by running `pub get` (if needed) and
+  /// initializing [collection] if that hasn't been done yet, and getting the
+  /// resolved library for `lib/analysis_warmup.dart` in the project.
+  ///
+  /// This is useful to run in a `setUpAll` so that the first test resolving a file
+  /// doesn't take abnormally long (e.g., if having consistent test times is
+  /// important, or if the first test might have a short timeout).
+  Future<void> warmUpAnalysis() async {
+    final path = p.join(contextRootPath, 'lib/analysis_warmup.dart');
+    await collection.contextFor(path).currentSession.getResolvedLibrary(path);
+  }
+
+  /// Creates a new file within [_testFileSubpath] with the name [filename]
+  /// (or a generated filename if not specified) and the given [sourceText]
+  /// and returns a codemod FileContext for that file.
+  ///
+  /// Throws if [filename] has already been used before in this instance,
+  /// to prevent the wrong results from being returned.
+  /// Since there's no public analyzer API to get an updated result for a file
+  /// that has been modified, reusing a file name means that [collection] or
+  /// the returned context backed by [collection] could return results for a previous
+  /// call to this method, and not results containing the updated [sourceText].
+  /// And, even if there were a way to update it, reusing file names would be prone
+  /// to race conditions, so this restriction will likely never be removed.
+  String createTestFile(String sourceText, {String? filename}) {
+    filename ??= nextFilename();
+    final path = p.join(contextRootPath, _testFileSubpath, filename);
+    final file = File(path);
+    if (file.existsSync()) {
+      throw StateError('File already exists: $filename.'
+          ' Cannot use an existing file, since there is no public API'
+          ' to update a file within a AnalysisContextCollection.'
+          ' Make sure you\'re using a unique filename each time.'
+          ' This error can also occur if there are concurrent test runs'
+          ' and `_testFileSubpath` is not namespaced.');
+    }
+    file.parent.createSync(recursive: true);
+    file.writeAsStringSync(sourceText);
+
+    // Assert that this doesn't throw a StateError due to this file not
+    // existing in the context we've set up (which shouldn't ever happen).
+    collection.contextFor(path);
+
+    return path;
+  }
+
+  int _fileNameCounter = 0;
+
+  /// Returns a filename that hasn't been used before.
+  String nextFilename() => 'test_${_fileNameCounter++}.dart';
+}
+
+/// A function that returns whether an error is expected and thus should be ignored
+typedef IsExpectedError = bool Function(AnalysisError);
+
+/// Checks [result] (usually the return value of a call to `AnalysisSession.getResolvedLibrary2`)
+/// and throws if:
+///
+/// - there were any issues getting the resolved result
+/// - there are analysis errors (other than those for which [isExpectedError] returns `true`)
+///   that are either have an `error` severity or are otherwise potentially problematic
+///   (e.g., unused members, which may mean there's a typo in the test)
+void checkResolvedResultForErrors(
+  SomeResolvedLibraryResult result, {
+  IsExpectedError? isExpectedError,
+}) {
+  isExpectedError ??= (_) => false;
+
+  const sharedMessage = 'If analysis errors are expected for this test, either:'
+      '\n1. specify `isExpectedError` with a function that returns true'
+      ' only for your expected error'
+      '\n2. use an `ignore:` comment to silence them'
+      '\n3. set `throwOnAnalysisErrors: false`,'
+      ' and use `checkResolvedResultForErrors` with `isExpectedError`'
+      ' to verify that only the expected errors are present.';
+
+  if (result is! ResolvedLibraryResult) {
+    throw ArgumentError(['Error resolving file; result was $result.', sharedMessage].join(' '));
+  }
+
+  final unexpectedErrors = result.units
+      .expand((unit) => unit.errors)
+      .where((error) =>
+          error.severity == Severity.error ||
+          const {
+            'unused_element',
+            'unused_local_variable',
+          }.contains(error.errorCode.name.toLowerCase()))
+      // We need a non-null-assertion here due to https://github.com/dart-lang/sdk/issues/40790
+      .where((error) => !isExpectedError!(error))
+      .toList();
+  if (unexpectedErrors.isNotEmpty) {
+    throw ArgumentError([
+      // ignore: no_adjacent_strings_in_list
+      'File had analysis errors or unused element hints,'
+          ' which likely indicate that the test file is set up improperly,'
+          ' potentially resulting in false positives in your test.',
+      sharedMessage,
+      'Errors:\n${prettyPrintErrors(unexpectedErrors)}.'
+    ].join(' '));
+  }
+}
+
+extension FileSystemDeleteIfExistExtension on FileSystemEntity {
+  void deleteSyncIfExists({bool recursive = false}) {
+    if (existsSync()) {
+      deleteSync(recursive: recursive);
+    }
+  }
+
+  Future<void> deleteIfExists({bool recursive = false}) async {
+    if (existsSync()) {
+      await delete(recursive: recursive);
+    }
+  }
+}
diff --git a/tools/analyzer_plugin/test/util/util.dart b/tools/analyzer_plugin/test/util/util.dart
new file mode 100644
index 000000000..32426c367
--- /dev/null
+++ b/tools/analyzer_plugin/test/util/util.dart
@@ -0,0 +1,21 @@
+// From https://github.com/Workiva/over_react_codemod/blob/a14a4ef372a1b2c2a625755cec7a6f956a074650/lib/src/util.dart
+import 'package:analyzer/error/error.dart';
+import 'package:analyzer/source/line_info.dart';
+
+String prettyPrintErrors(Iterable<AnalysisError> errors,
+    {LineInfo? lineInfo, bool includeFilename = true}) {
+  return errors.map((e) {
+    final severity = e.errorCode.errorSeverity.name.toLowerCase();
+    final errorCode = e.errorCode.name.toLowerCase();
+    final location =
+        lineInfo?.getLocation(e.offset).toString() ?? 'offset ${e.offset}';
+    final filename = e.source.shortName;
+
+    return " - [$severity] ${e.message} ($errorCode at${includeFilename ? ' $filename' : ''} $location)";
+  }).join('\n');
+}
+
+String blockComment(String contents) => '/*$contents*/';
+
+String lineComment(String contents) =>
+    contents.split('\n').map((line) => '// $line\n').join('');