Kapt3: Replace "my/package/Class$Inner" to "my/package/Class/Inner" in kapt3 class builder mode

compiler/backend/src/org/jetbrains/kotlin/codegen/ClassBuilderMode.java

@@ -62,4 +62,12 @@ public class ClassBuilderMode {
             /* bodies = */ false,
             /* metadata = */ true,
             /* sourceRetention = */ true);
+
+    /**
+     * Function signatures + metadata (to support incremental compilation with kapt)
+     */
+    public final static ClassBuilderMode KAPT3 = new ClassBuilderMode(
+            /* bodies = */ false,
+            /* metadata = */ true,
+            /* sourceRetention = */ true);
 }

compiler/backend/src/org/jetbrains/kotlin/codegen/binding/CodegenAnnotatingVisitor.java

@@ -41,6 +41,7 @@ import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor;
 import org.jetbrains.kotlin.fileClasses.FileClasses;
 import org.jetbrains.kotlin.fileClasses.JvmFileClassesProvider;
 import org.jetbrains.kotlin.load.java.descriptors.SamConstructorDescriptor;
+import org.jetbrains.kotlin.load.kotlin.TypeMappingConfiguration;
 import org.jetbrains.kotlin.name.Name;
 import org.jetbrains.kotlin.psi.*;
 import org.jetbrains.kotlin.resolve.BindingContext;
@@ -81,6 +82,7 @@ class CodegenAnnotatingVisitor extends KtVisitorVoid {
     private final GenerationState.GenerateClassFilter filter;
     private final JvmRuntimeTypes runtimeTypes;
     private final JvmFileClassesProvider fileClassesProvider;
+    private final TypeMappingConfiguration<Type> typeMappingConfiguration;
 
     public CodegenAnnotatingVisitor(@NotNull GenerationState state) {
         this.bindingTrace = state.getBindingTrace();
@@ -88,6 +90,7 @@ class CodegenAnnotatingVisitor extends KtVisitorVoid {
         this.filter = state.getGenerateDeclaredClassFilter();
         this.runtimeTypes = state.getJvmRuntimeTypes();
         this.fileClassesProvider = state.getFileClassesProvider();
+        this.typeMappingConfiguration = state.getTypeMapper().getTypeMappingConfiguration();
     }
 
     @NotNull
@@ -232,8 +235,12 @@ class CodegenAnnotatingVisitor extends KtVisitorVoid {
     private String getName(ClassDescriptor classDescriptor) {
         String base = peekFromStack(nameStack);
         Name descriptorName = safeIdentifier(classDescriptor.getName());
-        return DescriptorUtils.isTopLevelDeclaration(classDescriptor) ? base.isEmpty() ? descriptorName
-                        .asString() : base + '/' + descriptorName : base + '$' + descriptorName;
+        if (DescriptorUtils.isTopLevelDeclaration(classDescriptor)) {
+            return base.isEmpty() ? descriptorName.asString() : base + '/' + descriptorName;
+        }
+        else {
+            return typeMappingConfiguration.getInnerClassNameFactory().invoke(base, descriptorName.asString());
+        }
     }
 
     @Override

compiler/backend/src/org/jetbrains/kotlin/codegen/inline/InlineCodegen.java

@@ -325,7 +325,7 @@ public class InlineCodegen extends CallGenerator {
         assert callableDescriptor instanceof DeserializedCallableMemberDescriptor : "Not a deserialized function or proper: " + callableDescriptor;
 
         KotlinTypeMapper.ContainingClassesInfo containingClasses =
-                KotlinTypeMapper.getContainingClassesForDeserializedCallable((DeserializedCallableMemberDescriptor) callableDescriptor);
+                state.getTypeMapper().getContainingClassesForDeserializedCallable((DeserializedCallableMemberDescriptor) callableDescriptor);
 
         final ClassId containerId = containingClasses.getImplClassId();
 

compiler/backend/src/org/jetbrains/kotlin/codegen/state/KotlinTypeMapper.java

@@ -21,6 +21,7 @@ import com.intellij.psi.PsiElement;
 import kotlin.Pair;
 import kotlin.Unit;
 import kotlin.collections.CollectionsKt;
+import kotlin.jvm.functions.Function2;
 import kotlin.jvm.functions.Function3;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -103,12 +104,32 @@ public class KotlinTypeMapper {
     private final boolean isJvm8Target;
 
     private final TypeMappingConfiguration<Type> typeMappingConfiguration = new TypeMappingConfiguration<Type>() {
+        private final Function2<String, String, String> defaultClassNameFactory
+                = TypeMappingConfiguration.Companion.getDEFAULT_INNER_CLASS_NAME_FACTORY();
+
+        private final Function2<String, String, String> innerClassNameFactory = new Function2<String, String, String>() {
+            @Override
+            public String invoke(String outer, String inner) {
+                if (classBuilderMode == ClassBuilderMode.KAPT3) {
+                    return outer + '/' + inner;
+                }
+
+                return defaultClassNameFactory.invoke(outer, inner);
+            }
+        };
+
         @NotNull
         @Override
         public KotlinType commonSupertype(@NotNull Collection<KotlinType> types) {
             return CommonSupertypes.commonSupertype(types);
         }
 
+        @NotNull
+        @Override
+        public Function2<String, String, String> getInnerClassNameFactory() {
+            return innerClassNameFactory;
+        }
+
         @Nullable
         @Override
         public Type getPredefinedTypeForClass(@NotNull ClassDescriptor classDescriptor) {
@@ -139,6 +160,11 @@ public class KotlinTypeMapper {
         this.isJvm8Target = isJvm8Target;
     }
 
+    @NotNull
+    public TypeMappingConfiguration<Type> getTypeMappingConfiguration() {
+        return typeMappingConfiguration;
+    }
+
     @NotNull
     public BindingContext getBindingContext() {
         return bindingContext;
@@ -250,7 +276,7 @@ public class KotlinTypeMapper {
     }
 
     @NotNull
-    public static ContainingClassesInfo getContainingClassesForDeserializedCallable(
+    public ContainingClassesInfo getContainingClassesForDeserializedCallable(
             @NotNull DeserializedCallableMemberDescriptor deserializedDescriptor
     ) {
         DeclarationDescriptor parentDeclaration = deserializedDescriptor.getContainingDeclaration();
@@ -269,14 +295,16 @@ public class KotlinTypeMapper {
     }
 
     @NotNull
-    private static ClassId getContainerClassIdForClassDescriptor(@NotNull ClassDescriptor classDescriptor) {
+    private ClassId getContainerClassIdForClassDescriptor(@NotNull ClassDescriptor classDescriptor) {
         ClassId classId = DescriptorUtilsKt.getClassId(classDescriptor);
         assert classId != null : "Deserialized class should have a ClassId: " + classDescriptor;
 
         if (isInterface(classDescriptor)) {
             FqName relativeClassName = classId.getRelativeClassName();
             //TODO test nested trait fun inlining
-            return new ClassId(classId.getPackageFqName(), Name.identifier(relativeClassName.shortName().asString() + JvmAbi.DEFAULT_IMPLS_SUFFIX));
+            String defaultImplsClassName = typeMappingConfiguration.getInnerClassNameFactory()
+                    .invoke(relativeClassName.shortName().asString(), JvmAbi.DEFAULT_IMPLS_CLASS_NAME);
+            return new ClassId(classId.getPackageFqName(), Name.identifier(defaultImplsClassName));
         }
 
         return classId;
@@ -437,7 +465,9 @@ public class KotlinTypeMapper {
 
     @NotNull
     public Type mapDefaultImpls(@NotNull ClassDescriptor descriptor) {
-        return Type.getObjectType(mapType(descriptor).getInternalName() + JvmAbi.DEFAULT_IMPLS_SUFFIX);
+        String defaultImplsClassName = typeMappingConfiguration.getInnerClassNameFactory().invoke(
+                mapType(descriptor).getInternalName(), JvmAbi.DEFAULT_IMPLS_CLASS_NAME);
+        return Type.getObjectType(defaultImplsClassName);
     }
 
     @NotNull