Fix snake case deserialization

jr-annotation-support/pom.xml

@@ -76,6 +76,14 @@
         <groupId>de.jjohannes</groupId>
         <artifactId>gradle-module-metadata-maven-plugin</artifactId>
       </plugin>
+        <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+                <source>16</source>
+                <target>16</target>
+            </configuration>
+        </plugin>
     </plugins>
   </build>
 

jr-annotation-support/src/main/java/com/fasterxml/jackson/jr/annotationsupport/AnnotationBasedIntrospector.java

@@ -16,6 +16,7 @@
 import com.fasterxml.jackson.jr.ob.impl.JSONReader;
 import com.fasterxml.jackson.jr.ob.impl.JSONWriter;
 import com.fasterxml.jackson.jr.ob.impl.POJODefinition;
+import com.fasterxml.jackson.jr.ob.impl.RecordsHelpers;
 
 /**
  *
@@ -91,18 +92,30 @@ protected POJODefinition introspectDefinition()
             constructors = null;
         } else {
             constructors = new BeanConstructors(_type);
-            for (Constructor<?> ctor : _type.getDeclaredConstructors()) {
-                Class<?>[] argTypes = ctor.getParameterTypes();
-                if (argTypes.length == 0) {
-                    constructors.addNoArgsConstructor(ctor);
-                } else if (argTypes.length == 1) {
-                    Class<?> argType = argTypes[0];
-                    if (argType == String.class) {
-                        constructors.addStringConstructor(ctor);
-                    } else if (argType == Integer.class || argType == Integer.TYPE) {
-                        constructors.addIntConstructor(ctor);
-                    } else if (argType == Long.class || argType == Long.TYPE) {
-                        constructors.addLongConstructor(ctor);
+            if (RecordsHelpers.isRecordType(_type)) {
+                Constructor<?> canonical = RecordsHelpers.findCanonicalConstructor(_type);
+                constructors.addRecordConstructor(canonical);
+                for (int i = 0; i < canonical.getParameterCount(); i++) {
+                    Parameter ctorParam = canonical.getParameters()[i];
+                    final String explName = _findExplicitName(ctorParam);
+                    if (explName != null) {
+                        constructors.addRecordConstructorAlias(explName, ctorParam.getType(), i);
+                    }
+                }
+            } else {
+                for (Constructor<?> ctor : _type.getDeclaredConstructors()) {
+                    Class<?>[] argTypes = ctor.getParameterTypes();
+                    if (argTypes.length == 0) {
+                        constructors.addNoArgsConstructor(ctor);
+                    } else if (argTypes.length == 1) {
+                        Class<?> argType = argTypes[0];
+                        if (argType == String.class) {
+                            constructors.addStringConstructor(ctor);
+                        } else if (argType == Integer.class || argType == Integer.TYPE) {
+                            constructors.addIntConstructor(ctor);
+                        } else if (argType == Long.class || argType == Long.TYPE) {
+                            constructors.addLongConstructor(ctor);
+                        }
                     }
                 }
             }

jr-annotation-support/src/test/java/com/fasterxml/jackson/jr/annotationsupport/BasicAliasTest.java

@@ -3,6 +3,7 @@
 import org.junit.jupiter.api.Test;
 
 import com.fasterxml.jackson.annotation.JsonAlias;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.jr.ob.JSON;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -34,6 +35,11 @@ public String getMiddle() {
         public void setLast(String str) { last = str; }
     }
 
+    record SnakeCaseRecord(
+        @JsonProperty("first_name") String firstName,
+        @JsonProperty("last_name") String lastName
+    ) {}
+
     /*
     /**********************************************************************
     /* Test methods
@@ -62,4 +68,20 @@ public void testSimpleAliases() throws Exception
         assertEquals("Bob", result.middle);
         assertEquals("Burger", result.last);
     }
+
+    public void testSnakeCaseRecordDeserialization() throws Exception
+    {
+        final String input = a2q("{ 'first_name':'John', 'last_name':'Doe' }");
+        SnakeCaseRecord result;
+
+        // First: without setting, nothing matches
+        result = JSON.std.beanFrom(SnakeCaseRecord.class, input);
+        assertNull(result.firstName());
+        assertNull(result.lastName());
+
+        // but with annotations it's all good...
+        result = JSON_WITH_ANNO.beanFrom(SnakeCaseRecord.class, input);
+        assertEquals("John", result.firstName());
+        assertEquals("Doe", result.lastName());
+    }
 }

jr-annotation-support/src/test/java/com/fasterxml/jackson/jr/annotationsupport/BasicIgnoralTest.java

@@ -4,6 +4,7 @@
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.jr.ob.JSON;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
@@ -47,6 +48,11 @@ public XYZ(int x, int y, int z) {
         }
     }
 
+    record SnakeCaseRecord(
+        @JsonIgnore int x,
+        @JsonProperty("y_value") int y
+    ) {}
+
     private final JSON JSON_WITH_ANNO = jsonWithAnnotationSupport();
     private final JSON JSON_WITH_ANNO_WITH_STATIC =
             JSON.builder().register(JacksonAnnotationExtension.std).enable(JSON.Feature.INCLUDE_STATIC_FIELDS).build();
@@ -118,6 +124,23 @@ public void testPropertyIgnoreWithUnknown() throws Exception
         assertEquals(new XY().x, result.x);
     }
 
+//    Probably another bug that needs to be fixed. First I'm focusing on the deserialization of records.
+//
+//    public void testSnakeCaseRecordDeserialization() throws Exception
+//    {
+//        final String input = a2q("{ 'x':1, 'y_value':2 }");
+//        SnakeCaseRecord result;
+//
+//        // First: without setting, nothing matches
+//        result = JSON.std.beanFrom(SnakeCaseRecord.class, input);
+//        assertNull(result);
+//
+//        // but with annotations it's all good...
+//        result = JSON_WITH_ANNO.beanFrom(SnakeCaseRecord.class, input);
+//        assertEquals(0, result.x());
+//        assertEquals(2, result.y());
+//    }
+
     /*
     /**********************************************************************
     /* Tests for @JsonIgnoreProperties

jr-annotation-support/src/test/java/com/fasterxml/jackson/jr/annotationsupport/BasicRenameTest.java

@@ -116,7 +116,10 @@ public static SubclassingEnum from(String id) {
         }
     }
 
-
+    record SnakeCaseRecord(
+        @JsonProperty("first_name") String firstName,
+        @JsonProperty("last_name") String lastName
+    ) {}
 
     /*
     /**********************************************************************

jr-annotation-support/src/test/java/com/fasterxml/jackson/jr/annotationsupport/BasicReorderTest.java

@@ -1,7 +1,7 @@
 package com.fasterxml.jackson.jr.annotationsupport;
 
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
-
+import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.jr.ob.JSON;
 import org.junit.jupiter.api.Test;
 
@@ -40,6 +40,11 @@ public FullNameBean(String f, String m, String l) {
         public void setLast(String n) { last = n; }
     }
 
+    record SnakeCaseRecord(
+        @JsonProperty("first_name") String firstName,
+        @JsonProperty("last_name") String lastName
+    ) {}
+
     private final JSON JSON_WITH_ANNO = jsonWithAnnotationSupport();
 
     @Test
@@ -73,4 +78,20 @@ public void testPartialReorder() throws Exception
         // and ensure no leakage to default one:
         assertEquals(EXP_DEFAULT, JSON.std.asString(input));
     }
+
+    public void testSnakeCaseRecordDeserialization() throws Exception
+    {
+        final String input = a2q("{ 'first_name':'John', 'last_name':'Doe' }");
+        SnakeCaseRecord result;
+
+        // First: without setting, nothing matches
+        result = JSON.std.beanFrom(SnakeCaseRecord.class, input);
+        assertNull(result.firstName());
+        assertNull(result.lastName());
+
+        // but with annotations it's all good...
+        result = JSON_WITH_ANNO.beanFrom(SnakeCaseRecord.class, input);
+        assertEquals("John", result.firstName());
+        assertEquals("Doe", result.lastName());
+    }
 }

jr-objects/pom.xml

@@ -67,6 +67,14 @@ has no other dependencies, and provides additional builder-style content generat
         <groupId>de.jjohannes</groupId>
         <artifactId>gradle-module-metadata-maven-plugin</artifactId>
       </plugin>
+        <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+                <source>16</source>
+                <target>16</target>
+            </configuration>
+        </plugin>
     </plugins>
   </build>
 </project>

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/BeanConstructors.java

@@ -1,6 +1,10 @@
 package com.fasterxml.jackson.jr.ob.impl;
 
+import com.fasterxml.jackson.jr.ob.api.ValueReader;
+
 import java.lang.reflect.Constructor;
+import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Container class added to encapsulate details of collection and use of
@@ -10,6 +14,9 @@
  */
 public class BeanConstructors
 {
+    public record RecordAlias(ValueReader reader, Integer pos) {
+
+    }
     protected final Class<?> _valueType;
 
     protected Constructor<?> _noArgsCtor;
@@ -21,10 +28,17 @@ public class BeanConstructors
      */
     protected Constructor<?> _recordCtor;
 
+    /**
+     * Aliases for Record constructor parameters.
+     *
+     * @since 2.20
+     */
+    protected Map<String, RecordAlias> _recordCtorAliases = new HashMap<>();
+
     protected Constructor<?> _intCtor;
+
     protected Constructor<?> _longCtor;
     protected Constructor<?> _stringCtor;
-
     public BeanConstructors(Class<?> valueType) {
         _valueType = valueType;
     }
@@ -42,6 +56,14 @@ public BeanConstructors addRecordConstructor(Constructor<?> ctor) {
         return this;
     }
 
+    /**
+     * @since 2.20
+     */
+    public BeanConstructors addRecordConstructorAlias(String alias, Class<?> valueType, int pos) {
+        _recordCtorAliases.put(alias, new RecordAlias(new SimpleValueReader(valueType, 9), pos)); // TODO: Should not always be a simplevaluereader
+        return this;
+    }
+
     public BeanConstructors addIntConstructor(Constructor<?> ctor) {
         _intCtor = ctor;
         return this;
@@ -57,6 +79,14 @@ public BeanConstructors addStringConstructor(Constructor<?> ctor) {
         return this;
     }
 
+    public RecordAlias getRecordCtorAliasValueReader(String name) {
+        return _recordCtorAliases.get(name);
+    }
+
+    public int getRecordCtorAliasesCount() {
+        return _recordCtorAliases.size();
+    }
+
     public void forceAccess() {
         if (_noArgsCtor != null) {
             _noArgsCtor.setAccessible(true);

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/BeanReader.java

@@ -137,10 +137,17 @@ public Object readNext(JSONReader r, JsonParser p) throws IOException
     }
 
     private Object readRecord(JSONReader r, JsonParser p) throws Exception {
-        final Object[] values = new Object[_propsByName.size()];
+        final Object[] values = new Object[_propsByName.size() + _constructors.getRecordCtorAliasesCount()];
 
         String propName;
         for (; (propName = p.nextFieldName()) != null;) {
+            BeanConstructors.RecordAlias recAlias;
+            if ((recAlias = _constructors.getRecordCtorAliasValueReader(propName)) != null) {
+                values[recAlias.pos()] = recAlias.reader().readNext(r, p);
+
+                continue;
+            }
+
             BeanPropertyReader prop = findProperty(propName);
             if (prop == null) {
                 handleUnknown(r, p, propName);

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/RecordsHelpers.java

@@ -37,7 +37,7 @@ public final class RecordsHelpers {
     }
     private RecordsHelpers() {}
 
-    static Constructor<?> findCanonicalConstructor(Class<?> beanClass) {
+    public static Constructor<?> findCanonicalConstructor(Class<?> beanClass) {
         // sanity check: caller shouldn't rely on it
         if (!supportsRecords || !isRecordType(beanClass)) {
             return null;
@@ -78,7 +78,7 @@ static boolean isRecordConstructor(Class<?> beanClass, Constructor<?> ctor,
         }
     }
 
-    static boolean isRecordType(Class<?> cls) {
+    public static boolean isRecordType(Class<?> cls) {
         Class<?> parent = cls.getSuperclass();
         return (parent != null) && "java.lang.Record".equals(parent.getName());
     }