[analyzer][cfe] Add isDartCoreRecord to the shared methods

This is done by analogy with `isDartCoreFunction` and is used
similarly in the type constraint generation methods.

Part of #54902

Change-Id: Ied3a4e5ee55846c9c0f7e68dbcdff87548b94787
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/394100
Commit-Queue: Chloe Stefantsova <[email protected]>
Reviewed-by: Paul Berry <[email protected]>

pkg/_fe_analyzer_shared/lib/src/type_inference/type_analyzer_operations.dart

@@ -174,9 +174,13 @@ abstract interface class TypeAnalyzerOperations<
       SharedTypeView<TypeStructure> toType);
 
   /// Returns `true` if [type] is `Function` from `dart:core`. The method
-  /// returns `false` for `Object?` and `Object*`.
+  /// returns `false` for `Function?` and `Function*`.
   bool isDartCoreFunction(SharedTypeView<TypeStructure> type);
 
+  /// Returns `true` if [type] is `Record` from `dart:core`. The method
+  /// returns `false` for `Record?` and `Record*`.
+  bool isDartCoreRecord(SharedTypeView<TypeStructure> type);
+
   /// Returns `true` if [type] is `E<T1, ..., Tn>`, `E<T1, ..., Tn>?`, or
   /// `E<T1, ..., Tn>*` for some extension type declaration E, some
   /// non-negative n, and some types T1, ..., Tn.

pkg/_fe_analyzer_shared/test/mini_ast.dart

@@ -2959,6 +2959,15 @@ class MiniAstOperations
         unwrappedType.args.isEmpty;
   }
 
+  @override
+  bool isDartCoreRecord(SharedTypeView<Type> type) {
+    Type unwrappedType = type.unwrapTypeView();
+    return unwrappedType is PrimaryType &&
+        unwrappedType.nullabilitySuffix == NullabilitySuffix.none &&
+        unwrappedType.name == 'Record' &&
+        unwrappedType.args.isEmpty;
+  }
+
   @override
   bool isExtensionType(SharedTypeView<Type> type) {
     // TODO(cstefantsova): Add the support for extension types in the mini ast

pkg/_fe_analyzer_shared/test/type_inference/type_constraint_gatherer_test.dart

@@ -538,6 +538,34 @@ main() {
           .isFalse();
       check(tcg._constraints).isEmpty();
     });
+
+    test('Nullable does not match non-nullable', () {
+      // `(int, T)? <# (int, String)` does not match
+      var tcg = _TypeConstraintGatherer({'T'});
+      check(tcg.performSubtypeConstraintGenerationForLeftNullableType(
+              Type('(int, T)?'), Type('(int, String)'),
+              leftSchema: false, astNodeForTesting: Node.placeholder()))
+          .isFalse();
+      check(tcg._constraints).isEmpty();
+    });
+
+    test('Both LHS and RHS nullable, matching', () {
+      var tcg = _TypeConstraintGatherer({'T'});
+      check(tcg.performSubtypeConstraintGenerationForRightNullableType(
+              Type('T?'), Type('int?'),
+              leftSchema: false, astNodeForTesting: Node.placeholder()))
+          .isTrue();
+      check(tcg._constraints).deepEquals(['T <: int']);
+    });
+
+    test('Both LHS and RHS nullable, not matching', () {
+      var tcg = _TypeConstraintGatherer({'T'});
+      check(tcg.performSubtypeConstraintGenerationForRightNullableType(
+              Type('(T, int)?'), Type('(int, String)?'),
+              leftSchema: false, astNodeForTesting: Node.placeholder()))
+          .isFalse();
+      check(tcg._constraints).isEmpty();
+    });
   });
 
   group('performSubtypeConstraintGenerationForRightNullableType:', () {
@@ -583,6 +611,33 @@ main() {
           .isTrue();
       check(tcg._constraints).isEmpty();
     });
+
+    test('Dynamic matches Object?', () {
+      var tcg = _TypeConstraintGatherer({});
+      check(tcg.performSubtypeConstraintGenerationForRightNullableType(
+              Type('dynamic'), Type('Object?'),
+              leftSchema: false, astNodeForTesting: Node.placeholder()))
+          .isTrue();
+      check(tcg._constraints).isEmpty();
+    });
+
+    test('void matches Object?', () {
+      var tcg = _TypeConstraintGatherer({});
+      check(tcg.performSubtypeConstraintGenerationForRightNullableType(
+              Type('void'), Type('Object?'),
+              leftSchema: false, astNodeForTesting: Node.placeholder()))
+          .isTrue();
+      check(tcg._constraints).isEmpty();
+    });
+
+    test('LHS not nullable, matches with no constraints', () {
+      var tcg = _TypeConstraintGatherer({});
+      check(tcg.performSubtypeConstraintGenerationForRightNullableType(
+              Type('int'), Type('int?'),
+              leftSchema: false, astNodeForTesting: Node.placeholder()))
+          .isTrue();
+      check(tcg._constraints).isEmpty();
+    });
   });
 
   group('performSubtypeConstraintGenerationForTypeDeclarationTypes', () {

pkg/analyzer/lib/src/dart/element/type_constraint_gatherer.dart

@@ -368,7 +368,7 @@ class TypeConstraintGatherer extends shared.TypeConstraintGenerator<
     // A type `P` is a subtype match for `Record` with respect to `L` under no
     // constraints:
     //   If `P` is a record type or `Record`.
-    if (Q_nullability == NullabilitySuffix.none && Q.isDartCoreRecord) {
+    if (_typeSystemOperations.isDartCoreRecord(SharedTypeView(Q))) {
       if (P is SharedRecordTypeStructure<DartType>) {
         return true;
       }

pkg/analyzer/lib/src/dart/resolver/flow_analysis_visitor.dart

@@ -543,6 +543,12 @@ class TypeSystemOperations
         type.unwrapTypeView().isDartCoreFunction;
   }
 
+  @override
+  bool isDartCoreRecord(SharedTypeView<DartType> type) {
+    return type.nullabilitySuffix == NullabilitySuffix.none &&
+        type.unwrapTypeView().isDartCoreRecord;
+  }
+
   @override
   bool isExtensionType(SharedTypeView<DartType> type) {
     DartType unwrappedType = type.unwrapTypeView();

pkg/front_end/lib/src/type_inference/type_constraint_gatherer.dart

@@ -480,7 +480,7 @@ class TypeConstraintGatherer extends shared.TypeConstraintGenerator<
     // constraints:
     //
     // If P is a record type or Record.
-    if (q == _environment.coreTypes.recordNonNullableRawType &&
+    if (typeOperations.isDartCoreRecord(new SharedTypeView(q)) &&
         p is RecordType) {
       return true;
     }

pkg/front_end/lib/src/type_inference/type_inference_engine.dart

@@ -986,6 +986,12 @@ class OperationsCfe
         typeEnvironment.coreTypes.functionNonNullableRawType;
   }
 
+  @override
+  bool isDartCoreRecord(SharedTypeView<DartType> type) {
+    return type.unwrapTypeView() ==
+        typeEnvironment.coreTypes.recordNonNullableRawType;
+  }
+
   @override
   DartType greatestClosureOfTypeInternal(DartType type,
       List<SharedTypeParameterStructure<DartType>> typeParametersToEliminate) {

pkg/front_end/test/coverage_suite_expected.dart

@@ -1036,7 +1036,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/type_constraint_gatherer.dart": (
-    hitCount: 189,
+    hitCount: 188,
     missCount: 0,
   ),
   // 100.0%.
@@ -1046,7 +1046,7 @@ const Map<String, ({int hitCount, int missCount})> _expect = {
   ),
   // 100.0%.
   "package:front_end/src/type_inference/type_inference_engine.dart": (
-    hitCount: 530,
+    hitCount: 536,
     missCount: 0,
   ),
   // 100.0%.