Non static nested class construction (#297)

Construct the non-static nested classes correctly

jnigen/java/src/main/java/com/github/dart_lang/jnigen/apisummarizer/disasm/TypeUtils.java

@@ -20,7 +20,11 @@
 class TypeUtils {
 
   public static String parentName(Type type) {
-    return type.getClassName().split("\\$")[0];
+    var className = type.getClassName();
+    if (!className.contains("$")) {
+      return null;
+    }
+    return className.split("\\$")[0];
   }
 
   public static String simpleName(Type type) {

jnigen/lib/src/bindings/c_generator.dart

@@ -390,9 +390,12 @@ class _CParamGenerator extends Visitor<Param, String> {
   @override
   String visit(Param node) {
     final paramName =
-        _cTypeKeywords.contains(node.name) ? '${node.name}0' : node.name;
-    final type = node.type.accept(const _CReturnType());
-    if (addReturnType) return '$type $paramName';
+        (_cTypeKeywords.contains(node.name) ? '${node.name}0' : node.name)
+            .replaceAll('\$', '_');
+    if (addReturnType) {
+      final type = node.type.accept(const _CReturnType());
+      return '$type $paramName';
+    }
     return paramName;
   }
 }

jnigen/lib/src/bindings/dart_generator.dart

@@ -333,7 +333,7 @@ class _ClassGenerator extends Visitor<ClassDecl, void> {
         .map((typeParam) => 'this.$typeParam,')
         .join(_newLine(depth: 2));
     final superClass = (node.classDecl.superclass!.type as DeclaredType);
-    final superTypeClassesCall = superClass.classDecl.isObject()
+    final superTypeClassesCall = superClass.classDecl.isObject
         ? ''
         : superClass.params
             .accept(_TypeClassGenerator(resolver))
@@ -1331,7 +1331,7 @@ class _TypeVarLocator extends TypeVisitor<Map<String, List<OutsideInBuffer>>> {
 
   @override
   Map<String, List<OutsideInBuffer>> visitDeclaredType(DeclaredType node) {
-    if (node.classDecl.isObject()) {
+    if (node.classDecl.isObject) {
       return {};
     }
     final offset = node.classDecl.allTypeParams.length - node.params.length;

jnigen/lib/src/bindings/linker.dart

@@ -92,20 +92,7 @@ class _ClassLinker extends Visitor<ClassDecl, void> {
     log.finest('Linking ${node.binaryName}.');
     _linked.add(node);
 
-    node.parent = resolve(node.parentName);
-    node.parent!.accept(this);
-    // Add type params of outer classes to the nested classes
-    final allTypeParams = <TypeParam>[];
-    if (!node.modifiers.contains('static')) {
-      for (final typeParam in node.parent!.allTypeParams) {
-        if (!node.allTypeParams.contains(typeParam)) {
-          // Add only if it's not shadowing another type param.
-          allTypeParams.add(typeParam);
-        }
-      }
-    }
-    allTypeParams.addAll(node.typeParams);
-    node.allTypeParams = allTypeParams;
+    node.parent = node.parentName == null ? null : resolve(node.parentName);
 
     final typeLinker = _TypeLinker(resolve);
     node.superclass ??= TypeUsage.object;

jnigen/lib/src/bindings/renamer.dart

@@ -65,6 +65,7 @@ const Set<String> _keywords = {
   'throw',
   'true',
   'try',
+  'type', // Is used for type classes.
   'typedef',
   'var',
   'void',
@@ -213,8 +214,8 @@ class _MethodRenamer implements Visitor<Method, void> {
       node.finalName = _renameConflict(nameCounts, name);
       node.classDecl.methodNumsAfterRenaming[sig] = nameCounts[name]! - 1;
     }
-    log.fine(
-        'Method ${node.classDecl.binaryName}#${node.name} is named ${node.finalName}');
+    log.fine('Method ${node.classDecl.binaryName}#${node.name}'
+        ' is named ${node.finalName}');
 
     final paramRenamer = _ParamRenamer(config);
     for (final param in node.params) {
@@ -242,8 +243,8 @@ class _FieldRenamer implements Visitor<Field, void> {
       nameCounts,
       node.name,
     );
-    log.fine(
-        'Field ${node.classDecl.binaryName}#${node.name} is named ${node.finalName}');
+    log.fine('Field ${node.classDecl.binaryName}#${node.name}'
+        ' is named ${node.finalName}');
   }
 }
 

jnigen/lib/src/bindings/unnester.dart

@@ -0,0 +1,83 @@
+// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import '../elements/elements.dart';
+import 'visitor.dart';
+
+/// A [Visitor] that processes nested classes.
+///
+/// Nested classes are not supported in Dart. So this "unnests" them into
+/// separate classes.
+class Unnester extends Visitor<Classes, void> {
+  @override
+  void visit(node) {
+    final classProcessor = _ClassUnnester();
+    for (final classDecl in node.decls.values) {
+      classDecl.accept(classProcessor);
+    }
+  }
+}
+
+class _ClassUnnester extends Visitor<ClassDecl, void> {
+  final processed = <ClassDecl>{};
+
+  @override
+  void visit(ClassDecl node) {
+    if (processed.contains(node)) return;
+    processed.add(node);
+    // We need to visit the ancestors first.
+    node.parent?.accept(this);
+
+    // Add type params of outer classes to the nested classes.
+    final allTypeParams = <TypeParam>[];
+    if (!node.isStatic) {
+      allTypeParams.addAll(node.parent?.allTypeParams ?? []);
+    }
+    allTypeParams.addAll(node.typeParams);
+    node.allTypeParams = allTypeParams;
+
+    if (node.isNested && !node.isStatic) {
+      const methodProcessor = _MethodUnnester();
+      for (final method in node.methods) {
+        method.accept(methodProcessor);
+      }
+    }
+  }
+}
+
+class _MethodUnnester extends Visitor<Method, void> {
+  const _MethodUnnester();
+
+  @override
+  void visit(Method node) {
+    assert(!node.classDecl.isStatic);
+    assert(node.classDecl.isNested);
+    if (node.isCtor || node.isStatic) {
+      // Non-static nested classes take an instance of their outer class as the
+      // first parameter. This is not accounted for by the summarizer, so we
+      // manually add it as the first parameter.
+      final parentTypeParamCount = node.classDecl.allTypeParams.length -
+          node.classDecl.typeParams.length;
+      final parentTypeParams = [
+        for (final typeParam
+            in node.classDecl.allTypeParams.take(parentTypeParamCount)) ...[
+          TypeUsage(
+              shorthand: typeParam.name, kind: Kind.typeVariable, typeJson: {})
+            ..type = TypeVar(name: typeParam.name),
+        ]
+      ];
+      final parentType = DeclaredType(
+        binaryName: node.classDecl.parent!.binaryName,
+        params: parentTypeParams,
+      )..classDecl = node.classDecl.parent!;
+      final parentTypeUsage = TypeUsage(
+          shorthand: parentType.binaryName, kind: Kind.declared, typeJson: {})
+        ..type = parentType;
+      final param = Param(name: '\$parent', type: parentTypeUsage);
+      // Make the list modifiable.
+      if (node.params.isEmpty) node.params = [];
+      node.params.insert(0, param);
+    }
+  }
+}

jnigen/lib/src/config/config_types.dart

@@ -401,7 +401,8 @@ class Config {
             ..finalName = decl['name']
             ..typeClassName = decl['type_class']
             ..superCount = decl['super_count']
-            ..allTypeParams = [];
+            ..allTypeParams = []
+            ..parent = null;
           for (final typeParamEntry
               in ((decl['type_params'] as YamlMap?)?.entries) ??
                   <MapEntry<dynamic, dynamic>>[]) {

jnigen/lib/src/elements/elements.dart

@@ -167,7 +167,9 @@ class ClassDecl extends ClassMember implements Element<ClassDecl> {
   @override
   String get name => finalName;
 
-  bool isObject() => superCount == 0;
+  bool get isObject => superCount == 0;
+
+  bool get isNested => parentName != null;
 }
 
 @JsonEnum()
@@ -455,7 +457,7 @@ class Method extends ClassMember implements Element<Method> {
   final List<Annotation> annotations;
   final JavaDocComment? javadoc;
   final List<TypeParam> typeParams;
-  final List<Param> params;
+  List<Param> params;
   final TypeUsage returnType;
 
   /// The [ClassDecl] where this method is defined.

jnigen/lib/src/generate_bindings.dart

@@ -9,6 +9,7 @@ import 'bindings/c_generator.dart';
 import 'bindings/dart_generator.dart';
 import 'bindings/excluder.dart';
 import 'bindings/linker.dart';
+import 'bindings/unnester.dart';
 import 'bindings/renamer.dart';
 import 'elements/elements.dart';
 import 'summary/summary.dart';
@@ -36,6 +37,7 @@ Future<void> generateJniBindings(Config config) async {
 
   classes.accept(Excluder(config));
   await classes.accept(Linker(config));
+  classes.accept(Unnester());
   classes.accept(Renamer(config));
 
   final cBased = config.outputConfig.bindingsType == BindingsType.cBased;

jnigen/test/simple_package_test/c_based/c_bindings/simple_package.c

@@ -1513,20 +1513,21 @@ jclass _c_GrandParent_Parent = NULL;
 
 jmethodID _m_GrandParent_Parent__ctor = NULL;
 FFI_PLUGIN_EXPORT
-JniResult GrandParent_Parent__ctor(jobject parentValue, jobject value) {
+JniResult GrandParent_Parent__ctor(jobject _parent, jobject newValue) {
   load_env();
   load_class_global_ref(
       &_c_GrandParent_Parent,
       "com/github/dart_lang/jnigen/generics/GrandParent$Parent");
   if (_c_GrandParent_Parent == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
   load_method(_c_GrandParent_Parent, &_m_GrandParent_Parent__ctor, "<init>",
-              "(Ljava/lang/Object;Ljava/lang/Object;)V");
+              "(Lcom/github/dart_lang/jnigen/generics/GrandParent;Ljava/lang/"
+              "Object;)V");
   if (_m_GrandParent_Parent__ctor == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
   jobject _result =
       (*jniEnv)->NewObject(jniEnv, _c_GrandParent_Parent,
-                           _m_GrandParent_Parent__ctor, parentValue, value);
+                           _m_GrandParent_Parent__ctor, _parent, newValue);
   return to_global_ref_result(_result);
 }
 
@@ -1596,9 +1597,7 @@ jclass _c_GrandParent_Parent_Child = NULL;
 
 jmethodID _m_GrandParent_Parent_Child__ctor = NULL;
 FFI_PLUGIN_EXPORT
-JniResult GrandParent_Parent_Child__ctor(jobject grandParentValue,
-                                         jobject parentValue,
-                                         jobject value) {
+JniResult GrandParent_Parent_Child__ctor(jobject _parent, jobject newValue) {
   load_env();
   load_class_global_ref(
       &_c_GrandParent_Parent_Child,
@@ -1607,12 +1606,13 @@ JniResult GrandParent_Parent_Child__ctor(jobject grandParentValue,
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
   load_method(_c_GrandParent_Parent_Child, &_m_GrandParent_Parent_Child__ctor,
               "<init>",
-              "(Ljava/lang/Object;Ljava/lang/Object;Ljava/lang/Object;)V");
+              "(Lcom/github/dart_lang/jnigen/generics/GrandParent$Parent;Ljava/"
+              "lang/Object;)V");
   if (_m_GrandParent_Parent_Child__ctor == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
   jobject _result = (*jniEnv)->NewObject(jniEnv, _c_GrandParent_Parent_Child,
                                          _m_GrandParent_Parent_Child__ctor,
-                                         grandParentValue, parentValue, value);
+                                         _parent, newValue);
   return to_global_ref_result(_result);
 }
 
@@ -1773,22 +1773,25 @@ jclass _c_GrandParent_StaticParent_Child = NULL;
 
 jmethodID _m_GrandParent_StaticParent_Child__ctor = NULL;
 FFI_PLUGIN_EXPORT
-JniResult GrandParent_StaticParent_Child__ctor(jobject parentValue,
+JniResult GrandParent_StaticParent_Child__ctor(jobject _parent,
+                                               jobject parentValue,
                                                jobject value) {
   load_env();
   load_class_global_ref(
       &_c_GrandParent_StaticParent_Child,
       "com/github/dart_lang/jnigen/generics/GrandParent$StaticParent$Child");
   if (_c_GrandParent_StaticParent_Child == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
-  load_method(_c_GrandParent_StaticParent_Child,
-              &_m_GrandParent_StaticParent_Child__ctor, "<init>",
-              "(Ljava/lang/Object;Ljava/lang/Object;)V");
+  load_method(
+      _c_GrandParent_StaticParent_Child,
+      &_m_GrandParent_StaticParent_Child__ctor, "<init>",
+      "(Lcom/github/dart_lang/jnigen/generics/GrandParent$StaticParent;Ljava/"
+      "lang/Object;Ljava/lang/Object;)V");
   if (_m_GrandParent_StaticParent_Child__ctor == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
   jobject _result = (*jniEnv)->NewObject(
       jniEnv, _c_GrandParent_StaticParent_Child,
-      _m_GrandParent_StaticParent_Child__ctor, parentValue, value);
+      _m_GrandParent_StaticParent_Child__ctor, _parent, parentValue, value);
   return to_global_ref_result(_result);
 }
 
@@ -1934,18 +1937,19 @@ jclass _c_MyMap_MyEntry = NULL;
 
 jmethodID _m_MyMap_MyEntry__ctor = NULL;
 FFI_PLUGIN_EXPORT
-JniResult MyMap_MyEntry__ctor(jobject key, jobject value) {
+JniResult MyMap_MyEntry__ctor(jobject _parent, jobject key, jobject value) {
   load_env();
   load_class_global_ref(&_c_MyMap_MyEntry,
                         "com/github/dart_lang/jnigen/generics/MyMap$MyEntry");
   if (_c_MyMap_MyEntry == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
   load_method(_c_MyMap_MyEntry, &_m_MyMap_MyEntry__ctor, "<init>",
-              "(Ljava/lang/Object;Ljava/lang/Object;)V");
+              "(Lcom/github/dart_lang/jnigen/generics/MyMap;Ljava/lang/"
+              "Object;Ljava/lang/Object;)V");
   if (_m_MyMap_MyEntry__ctor == NULL)
     return (JniResult){.value = {.j = 0}, .exception = check_exception()};
-  jobject _result = (*jniEnv)->NewObject(jniEnv, _c_MyMap_MyEntry,
-                                         _m_MyMap_MyEntry__ctor, key, value);
+  jobject _result = (*jniEnv)->NewObject(
+      jniEnv, _c_MyMap_MyEntry, _m_MyMap_MyEntry__ctor, _parent, key, value);
   return to_global_ref_result(_result);
 }