fix: Use Python object for Score, handle descriptor correctly, do not copy parent fields

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/PythonClassTranslator.java

@@ -2,6 +2,7 @@
 
 import static ai.timefold.jpyinterpreter.PythonBytecodeToJavaBytecodeTranslator.ARGUMENT_SPEC_INSTANCE_FIELD_NAME;
 
+import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Modifier;
 import java.util.ArrayList;
@@ -38,6 +39,7 @@
 import ai.timefold.jpyinterpreter.types.BuiltinTypes;
 import ai.timefold.jpyinterpreter.types.CPythonBackedPythonLikeObject;
 import ai.timefold.jpyinterpreter.types.GeneratedFunctionMethodReference;
+import ai.timefold.jpyinterpreter.types.PythonJavaTypeMapping;
 import ai.timefold.jpyinterpreter.types.PythonLikeFunction;
 import ai.timefold.jpyinterpreter.types.PythonLikeType;
 import ai.timefold.jpyinterpreter.types.PythonNone;
@@ -65,6 +67,7 @@ public class PythonClassTranslator {
     public static final String TYPE_FIELD_NAME = "$TYPE";
     public static final String CPYTHON_TYPE_FIELD_NAME = "$CPYTHON_TYPE";
     private static final String JAVA_METHOD_PREFIX = "$method$";
+    private static final String PYTHON_JAVA_TYPE_MAPPING_PREFIX = "$pythonJavaTypeMapping";
 
     public record PreparedClassInfo(PythonLikeType type, String className, String classInternalName) {
     }
@@ -205,7 +208,25 @@ public static PythonLikeType translatePythonClass(PythonCompiledClass pythonComp
             }
         }
 
+        for (int i = 0; i < pythonCompiledClass.pythonJavaTypeMappings.size(); i++) {
+            classWriter.visitField(Modifier.PUBLIC | Modifier.STATIC, PYTHON_JAVA_TYPE_MAPPING_PREFIX + i,
+                    Type.getDescriptor(PythonJavaTypeMapping.class), null, null);
+        }
+
         Map<String, PythonLikeType> attributeNameToTypeMap = new HashMap<>();
+        instanceAttributeSet.removeAll(pythonCompiledClass.staticAttributeDescriptorNames);
+        try {
+            var parentClass = superClassType.getJavaClass();
+            while (parentClass != Object.class) {
+                for (Field field : parentClass.getFields()) {
+                    instanceAttributeSet.remove(field.getName());
+                }
+                parentClass = parentClass.getSuperclass();
+            }
+        } catch (ClassNotFoundException e) {
+            throw new IllegalStateException(e);
+        }
+
         for (String attributeName : instanceAttributeSet) {
             var typeHint = pythonCompiledClass.typeAnnotations.getOrDefault(attributeName,
                     TypeHint.withoutAnnotations(BuiltinTypes.BASE_TYPE));
@@ -243,8 +264,8 @@ public static PythonLikeType translatePythonClass(PythonCompiledClass pythonComp
             }
             fieldVisitor.visitEnd();
 
-            createJavaGetterSetter(classWriter, preparedClassInfo,
-                    attributeName,
+            createJavaGetterSetter(classWriter, pythonCompiledClass,
+                    preparedClassInfo, attributeName,
                     Type.getType(javaFieldTypeDescriptor),
                     Type.getType(getterTypeDescriptor),
                     signature,
@@ -368,6 +389,10 @@ public static PythonLikeType translatePythonClass(PythonCompiledClass pythonComp
             generatedClass = (Class<? extends PythonLikeObject>) BuiltinTypes.asmClassLoader.loadClass(className);
             generatedClass.getField(TYPE_FIELD_NAME).set(null, pythonLikeType);
             generatedClass.getField(CPYTHON_TYPE_FIELD_NAME).set(null, pythonCompiledClass.binaryType);
+            for (int i = 0; i < pythonCompiledClass.pythonJavaTypeMappings.size(); i++) {
+                generatedClass.getField(PYTHON_JAVA_TYPE_MAPPING_PREFIX + i)
+                        .set(null, pythonCompiledClass.pythonJavaTypeMappings.get(i));
+            }
         } catch (ClassNotFoundException e) {
             throw new IllegalStateException("Impossible State: Unable to load generated class (" +
                     className + ") despite it being just generated.", e);
@@ -785,16 +810,31 @@ private static PythonLikeFunction createConstructor(String classInternalName,
         }
     }
 
+    private record MatchedMapping(int index, PythonJavaTypeMapping<?, ?> pythonJavaTypeMapping) {
+    }
+
     private static void createJavaGetterSetter(ClassWriter classWriter,
+            PythonCompiledClass pythonCompiledClass,
             PreparedClassInfo preparedClassInfo,
             String attributeName, Type attributeType, Type getterType,
             String signature,
             TypeHint typeHint) {
-        createJavaGetter(classWriter, preparedClassInfo, attributeName, attributeType, getterType, signature, typeHint);
-        createJavaSetter(classWriter, preparedClassInfo, attributeName, attributeType, getterType, signature, typeHint);
+        MatchedMapping matchedMapping = null;
+        for (int i = 0; i < pythonCompiledClass.pythonJavaTypeMappings.size(); i++) {
+            var mapping = pythonCompiledClass.pythonJavaTypeMappings.get(i);
+            if (mapping.getPythonType().equals(typeHint.javaGetterType())) {
+                matchedMapping = new MatchedMapping(i, mapping);
+                getterType = Type.getType(mapping.getJavaType());
+            }
+        }
+        createJavaGetter(classWriter, preparedClassInfo, matchedMapping, attributeName, attributeType, getterType, signature,
+                typeHint);
+        createJavaSetter(classWriter, preparedClassInfo, matchedMapping, attributeName, attributeType, getterType, signature,
+                typeHint);
     }
 
-    private static void createJavaGetter(ClassWriter classWriter, PreparedClassInfo preparedClassInfo, String attributeName,
+    private static void createJavaGetter(ClassWriter classWriter, PreparedClassInfo preparedClassInfo,
+            MatchedMapping matchedMapping, String attributeName,
             Type attributeType, Type getterType, String signature, TypeHint typeHint) {
         var getterName = "get" + attributeName.substring(0, 1).toUpperCase() + attributeName.substring(1);
         if (signature != null && Objects.equals(attributeType, getterType)) {
@@ -826,14 +866,30 @@ private static void createJavaGetter(ClassWriter classWriter, PreparedClassInfo
             // If branch is not taken, stack is null
         }
         if (!Objects.equals(attributeType, getterType)) {
+            if (matchedMapping != null) {
+                getterVisitor.visitInsn(Opcodes.DUP);
+                getterVisitor.visitInsn(Opcodes.ACONST_NULL);
+                Label skipMapping = new Label();
+                getterVisitor.visitJumpInsn(Opcodes.IF_ACMPEQ, skipMapping);
+                getterVisitor.visitFieldInsn(Opcodes.GETSTATIC, preparedClassInfo.classInternalName,
+                        PYTHON_JAVA_TYPE_MAPPING_PREFIX + matchedMapping.index,
+                        Type.getDescriptor(PythonJavaTypeMapping.class));
+                getterVisitor.visitInsn(Opcodes.SWAP);
+                getterVisitor.visitMethodInsn(Opcodes.INVOKEINTERFACE,
+                        Type.getInternalName(PythonJavaTypeMapping.class), "toJavaObject",
+                        Type.getMethodDescriptor(Type.getType(Object.class), Type.getType(Object.class)),
+                        true);
+                getterVisitor.visitLabel(skipMapping);
+            }
             getterVisitor.visitTypeInsn(Opcodes.CHECKCAST, getterType.getInternalName());
         }
         getterVisitor.visitInsn(Opcodes.ARETURN);
         getterVisitor.visitMaxs(maxStack, 0);
         getterVisitor.visitEnd();
     }
 
-    private static void createJavaSetter(ClassWriter classWriter, PreparedClassInfo preparedClassInfo, String attributeName,
+    private static void createJavaSetter(ClassWriter classWriter, PreparedClassInfo preparedClassInfo,
+            MatchedMapping matchedMapping, String attributeName,
             Type attributeType, Type setterType, String signature, TypeHint typeHint) {
         var setterName = "set" + attributeName.substring(0, 1).toUpperCase() + attributeName.substring(1);
         if (signature != null && Objects.equals(attributeType, setterType)) {
@@ -861,6 +917,21 @@ private static void createJavaSetter(ClassWriter classWriter, PreparedClassInfo
             // If branch is not taken, stack is None
         }
         if (!Objects.equals(attributeType, setterType)) {
+            if (matchedMapping != null) {
+                setterVisitor.visitVarInsn(Opcodes.ALOAD, 1);
+                setterVisitor.visitInsn(Opcodes.ACONST_NULL);
+                Label skipMapping = new Label();
+                setterVisitor.visitJumpInsn(Opcodes.IF_ACMPEQ, skipMapping);
+                setterVisitor.visitFieldInsn(Opcodes.GETSTATIC, preparedClassInfo.classInternalName,
+                        PYTHON_JAVA_TYPE_MAPPING_PREFIX + matchedMapping.index,
+                        Type.getDescriptor(PythonJavaTypeMapping.class));
+                setterVisitor.visitInsn(Opcodes.SWAP);
+                setterVisitor.visitMethodInsn(Opcodes.INVOKEINTERFACE,
+                        Type.getInternalName(PythonJavaTypeMapping.class), "toPythonObject",
+                        Type.getMethodDescriptor(Type.getType(Object.class), Type.getType(Object.class)),
+                        true);
+                setterVisitor.visitLabel(skipMapping);
+            }
             setterVisitor.visitTypeInsn(Opcodes.CHECKCAST, attributeType.getInternalName());
         }
         setterVisitor.visitFieldInsn(Opcodes.PUTFIELD, preparedClassInfo.classInternalName,

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/PythonCompiledClass.java

@@ -2,7 +2,9 @@
 
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
+import ai.timefold.jpyinterpreter.types.PythonJavaTypeMapping;
 import ai.timefold.jpyinterpreter.types.PythonLikeType;
 import ai.timefold.jpyinterpreter.types.wrappers.CPythonType;
 import ai.timefold.jpyinterpreter.types.wrappers.OpaquePythonReference;
@@ -41,6 +43,11 @@ public class PythonCompiledClass {
      */
     public List<Class<?>> javaInterfaces;
 
+    /**
+     * Mapping from Python types to Java types
+     */
+    public List<PythonJavaTypeMapping<?, ?>> pythonJavaTypeMappings;
+
     /**
      * The binary type of this PythonCompiledClass;
      * typically {@link CPythonType}. Used when methods
@@ -62,6 +69,11 @@ public class PythonCompiledClass {
      */
     public Map<String, OpaquePythonReference> staticAttributeNameToClassInstance;
 
+    /**
+     * Contains static attributes that have get/set descriptors
+     */
+    public Set<String> staticAttributeDescriptorNames;
+
     public String getGeneratedClassBaseName() {
         return getGeneratedClassBaseName(module, qualifiedName);
     }

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/PythonLikeObject.java

@@ -125,8 +125,8 @@ public interface PythonLikeObject {
         return PythonBoolean.valueOf(!Objects.equals(this, other));
     }
 
-    default PythonLikeObject $method$__str__() {
-        return PythonString.valueOf(this.toString());
+    default PythonString $method$__str__() {
+        return PythonString.valueOf(this.getClass().getSimpleName() + "@" + System.identityHashCode(this));
     }
 
     default PythonLikeObject $method$__repr__() {

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/AbstractPythonLikeObject.java

@@ -49,4 +49,9 @@ public AbstractPythonLikeObject(PythonLikeType __type__, Map<String, PythonLikeO
     public void setAttribute(String attributeName, PythonLikeObject value) {
         __dir__.put(attributeName, value);
     }
+
+    @Override
+    public String toString() {
+        return $method$__str__().toString();
+    }
 }

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/Ellipsis.java

@@ -18,6 +18,11 @@ private Ellipsis() {
         super(ELLIPSIS_TYPE);
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         return "NotImplemented";

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/NotImplemented.java

@@ -17,6 +17,11 @@ private NotImplemented() {
         super(NOT_IMPLEMENTED_TYPE);
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         return "NotImplemented";

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/PythonByteArray.java

@@ -1914,6 +1914,11 @@ public PythonString repr() {
         return asString();
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         StringBuilder out = new StringBuilder(valueBuffer.limit());

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/PythonBytes.java

@@ -1686,6 +1686,11 @@ public PythonString repr() {
         return asString();
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         boolean hasSingleQuotes = false;

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/PythonJavaTypeMapping.java

@@ -0,0 +1,11 @@
+package ai.timefold.jpyinterpreter.types;
+
+public interface PythonJavaTypeMapping<PythonType_, JavaType_> {
+    PythonLikeType getPythonType();
+
+    Class<? extends JavaType_> getJavaType();
+
+    PythonType_ toPythonObject(JavaType_ javaObject);
+
+    JavaType_ toJavaObject(PythonType_ pythonObject);
+}

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/PythonLikeType.java

@@ -598,6 +598,11 @@ public List<PythonLikeType> getParentList() {
         return PARENT_TYPES;
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         return "<class " + TYPE_NAME + ">";

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/PythonNone.java

@@ -30,6 +30,11 @@ private PythonNone() {
         super(BuiltinTypes.NONE_TYPE);
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         return "None";

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/PythonString.java

@@ -1477,6 +1477,11 @@ public PythonString asString() {
         return this;
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return this;
+    }
+
     @Override
     public String toString() {
         return value;

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/collections/PythonLikeDict.java

@@ -402,6 +402,11 @@ public int hashCode() {
         return Objects.hash(delegate);
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         return delegate.toString();

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/collections/PythonLikeList.java

@@ -558,6 +558,11 @@ public List<T> subList(int i, int i1) {
         return delegate.subList(i, i1);
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         StringBuilder out = new StringBuilder();

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/collections/PythonLikeTuple.java

@@ -20,6 +20,7 @@
 import ai.timefold.jpyinterpreter.types.PythonLikeComparable;
 import ai.timefold.jpyinterpreter.types.PythonLikeType;
 import ai.timefold.jpyinterpreter.types.PythonSlice;
+import ai.timefold.jpyinterpreter.types.PythonString;
 import ai.timefold.jpyinterpreter.types.errors.TypeError;
 import ai.timefold.jpyinterpreter.types.errors.ValueError;
 import ai.timefold.jpyinterpreter.types.errors.lookup.IndexError;
@@ -444,6 +445,11 @@ public int hashCode() {
         return PythonInteger.valueOf(hashCode());
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         return delegate.toString();

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/datetime/PythonTime.java

@@ -328,8 +328,9 @@ public PythonString isoformat(PythonString formatSpec) {
         return PythonString.valueOf(result);
     }
 
-    public PythonString toPythonString() {
-        return new PythonString(localTime.toString());
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
     }
 
     @Override

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/datetime/PythonTimeDelta.java

@@ -339,6 +339,11 @@ public PythonBoolean isZero() {
         return PythonBoolean.valueOf(duration.isZero());
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         StringBuilder out = new StringBuilder();

jpyinterpreter/src/main/java/ai/timefold/jpyinterpreter/types/numeric/PythonBoolean.java

@@ -123,6 +123,11 @@ public static PythonBoolean valueOf(boolean result) {
         return BuiltinTypes.BOOLEAN_TYPE;
     }
 
+    @Override
+    public PythonString $method$__str__() {
+        return PythonString.valueOf(toString());
+    }
+
     @Override
     public String toString() {
         if (this == TRUE) {