feat(annotation): Annotations on superclasses are honored

This patch supports the following scenario:

```
class Base {
  @Ngattr('foo')
  var foo;
}

@ngdirective(selector:'my-directive')
class MyDirective extends Base {
  @Ngattr('bar')
  var bar;
}
```

MyDirective will now have both properties, foo and bar.

Closes #829

Author: mvuksano

lib/core/registry_dynamic.dart

@@ -57,24 +57,29 @@ class DynamicMetadataExtractor implements MetadataExtractor {
 
 
   Map<String, DirectiveAnnotation> fieldMetadataExtractor(Type type) =>
-      _fieldMetadataCache.putIfAbsent(type, () => _fieldMetadataExtractor(type));
+      _fieldMetadataCache.putIfAbsent(type, () => _fieldMetadataExtractor(reflectType(type)));
 
-  Map<String, DirectiveAnnotation> _fieldMetadataExtractor(Type type) {
-    ClassMirror cm = reflectType(type);
-    final fields = <String, DirectiveAnnotation>{};
-    cm.declarations.forEach((Symbol name, DeclarationMirror decl) {
-      if (decl is VariableMirror ||
-      decl is MethodMirror && (decl.isGetter || decl.isSetter)) {
-        var fieldName = MirrorSystem.getName(name);
-        if (decl is MethodMirror && decl.isSetter) {
+  Map<String, DirectiveAnnotation> _fieldMetadataExtractor(ClassMirror cm) {
+    var fields = <String, DirectiveAnnotation>{};
+    if(cm.superclass != null) {
+      fields.addAll(_fieldMetadataExtractor(cm.superclass));
+    } else {
+      fields = {};
+    }
+    Map<Symbol, DeclarationMirror> declarations = cm.declarations;
+    declarations.forEach((symbol, dm) {
+      if(dm is VariableMirror ||
+          dm is MethodMirror && (dm.isGetter || dm.isSetter)) {
+        var fieldName = MirrorSystem.getName(symbol);
+        if (dm is MethodMirror && dm.isSetter) {
           // Remove "=" from the end of the setter.
           fieldName = fieldName.substring(0, fieldName.length - 1);
         }
-        decl.metadata.forEach((InstanceMirror meta) {
+        dm.metadata.forEach((InstanceMirror meta) {
           if (_fieldAnnotations.contains(meta.type)) {
             if (fields.containsKey(fieldName)) {
               throw 'Attribute annotation for $fieldName is defined more '
-              'than once in $type';
+                'than once in ${cm.reflectedType}';
             }
             fields[fieldName] = meta.reflectee as DirectiveAnnotation;
           }

lib/tools/source_metadata_extractor.dart

@@ -1,6 +1,7 @@
 library angular.source_metadata_extractor ;
 
 import 'package:analyzer/src/generated/ast.dart';
+import 'package:analyzer/src/generated/element.dart';
 
 import 'package:angular/tools/source_crawler.dart';
 import 'package:angular/tools/common.dart';
@@ -181,34 +182,51 @@ class DirectiveMetadataCollectingAstVisitor extends RecursiveAstVisitor {
         }
       });
 
-      // Check fields/getters/setter for presense of attr mapping annotations.
-      clazz.members.forEach((ClassMember member) {
-        if (member is FieldDeclaration ||
-            (member is MethodDeclaration &&
-                (member.isSetter || member.isGetter))) {
-          member.metadata.forEach((Annotation ann) {
-            if (_attrAnnotationsToSpec.containsKey(ann.name.name)) {
-              String fieldName;
-              if (member is FieldDeclaration) {
-                fieldName = member.fields.variables.first.name.name;
-              } else { // MethodDeclaration
-                fieldName = (member as MethodDeclaration).name.name;
-              }
-              StringLiteral attNameLiteral = ann.arguments.arguments.first;
-              if (meta.attributeMappings
-                      .containsKey(attNameLiteral.stringValue)) {
-                throw 'Attribute mapping already defined for '
-                    '${clazz.name}.$fieldName';
-              }
-              meta.attributeMappings[attNameLiteral.stringValue] =
-                  _attrAnnotationsToSpec[ann.name.name] + fieldName;
-            }
-          });
-        }
-      });
+      if (meta != null) _walkSuperclassChain(clazz, meta, _extractMappingsFromClass);
     });
+
     return super.visitClassDeclaration(clazz);
   }
+
+  _walkSuperclassChain(ClassDeclaration clazz, DirectiveMetadata meta,
+                       metadataExtractor(ClassDeclaration clazz, DirectiveMetadata meta)) {
+    while (clazz != null) {
+      metadataExtractor(clazz, meta);
+      if (clazz.element != null && clazz.element.supertype != null) {
+        clazz = clazz.element.supertype.element.node;
+      } else {
+        clazz = null;
+      }
+    }
+  }
+
+  _extractMappingsFromClass(ClassDeclaration clazz, DirectiveMetadata meta) {
+    // Check fields/getters/setter for presence of attr mapping annotations.
+    clazz.members.forEach((ClassMember member) {
+      if (member is FieldDeclaration ||
+      (member is MethodDeclaration &&
+      (member.isSetter || member.isGetter))) {
+        member.metadata.forEach((Annotation ann) {
+          if (_attrAnnotationsToSpec.containsKey(ann.name.name)) {
+            String fieldName;
+            if (member is FieldDeclaration) {
+              fieldName = member.fields.variables.first.name.name;
+            } else { // MethodDeclaration
+              fieldName = (member as MethodDeclaration).name.name;
+            }
+            StringLiteral attNameLiteral = ann.arguments.arguments.first;
+            if (meta.attributeMappings
+            .containsKey(attNameLiteral.stringValue)) {
+              throw 'Attribute mapping already defined for '
+              '${clazz.name}.$fieldName';
+            }
+            meta.attributeMappings[attNameLiteral.stringValue] =
+            _attrAnnotationsToSpec[ann.name.name] + fieldName;
+          }
+        });
+      }
+    });
+  }
 }
 
 class DirectiveMetadataCollectingVisitor {

lib/tools/transformer/metadata_extractor.dart

@@ -242,20 +242,31 @@ class AnnotationExtractor {
 
   /// Extracts all of the annotations for the specified class.
   AnnotatedType extractAnnotations(ClassElement cls) {
-    if (resolver.getImportUri(cls.library, from: outputId) == null) {
-      warn('Dropping annotations for ${cls.name} because the '
-          'containing file cannot be imported (must be in a lib folder).', cls);
-      return null;
-    }
-
+    var classElement = cls;
     var visitor = new _AnnotationVisitor(_annotationElements);
-    cls.node.accept(visitor);
+    while (classElement != null) {
+      if (resolver.getImportUri(classElement.library, from: outputId) == null) {
+        warn('Dropping annotations for ${classElement.name} because the '
+            'containing file cannot be imported (must be in a lib folder).', classElement);
+        return null;
+      }
+      if (classElement.node != null) {
+        classElement.node.accept(visitor);
+      }
+
+      if (classElement.supertype != null) {
+        visitor.visitingSupertype = true;
+        classElement = classElement.supertype.element;
+      } else {
+        classElement = null;
+      }
+    }
 
     if (!visitor.hasAnnotations) return null;
 
     var type = new AnnotatedType(cls);
     type.annotations = visitor.classAnnotations
-        .where((annotation) {
+        .where((Annotation annotation) {
           var element = annotation.element;
           if (element != null && !element.isPublic) {
             warn('Annotation $annotation is not public.',
@@ -277,6 +288,7 @@ class AnnotationExtractor {
                  element.enclosingElement.type.isAssignableTo(formatterType.type);
         }).toList();
 
+    if (type.annotations.isEmpty) return null;
 
     var memberAnnotations = {};
     visitor.memberAnnotations.forEach((memberName, annotations) {
@@ -293,8 +305,6 @@ class AnnotationExtractor {
       _foldMemberAnnotations(memberAnnotations, type);
     }
 
-    if (type.annotations.isEmpty) return null;
-
     return type;
   }
 
@@ -309,10 +319,6 @@ class AnnotationExtractor {
       return element.enclosingElement.type.isAssignableTo(
           directiveType.type);
     });
-    if (ngAnnotations.isEmpty) {
-      warn('Found field annotation but no class directives.', type.type);
-      return;
-    }
 
     var mapType = resolver.getType('dart.core.Map').type;
     // Find acceptable constructors- ones which take a param named 'map'
@@ -410,15 +416,17 @@ class _AnnotationVisitor extends GeneralizingAstVisitor {
   final List<Element> allowedMemberAnnotations;
   final List<Annotation> classAnnotations = [];
   final Map<String, List<Annotation>> memberAnnotations = {};
+  var visitingSupertype = false;
 
   _AnnotationVisitor(this.allowedMemberAnnotations);
 
   void visitAnnotation(Annotation annotation) {
     var parent = annotation.parent;
     if (parent is! Declaration) return;
 
-    if (parent.element is ClassElement) {
+    if (parent.element is ClassElement && !visitingSupertype) {
       classAnnotations.add(annotation);
+
     } else if (allowedMemberAnnotations.contains(annotation.element)) {
       if (parent is MethodDeclaration) {
         memberAnnotations.putIfAbsent(parent.name.name, () => [])

perf/pubspec.lock

@@ -30,18 +30,15 @@ packages:
   code_transformers:
     description: code_transformers
     source: hosted
-    version: "0.1.1"
+    version: "0.1.3"
   collection:
     description: collection
     source: hosted
     version: "0.9.1"
   di:
-    description:
-      ref: null
-      resolved-ref: a2de00d84934f4610d1f9e108c39614e66a773f5
-      url: "git://github.com/angular/di.dart.git"
-    source: git
-    version: "0.0.34"
+    description: di
+    source: hosted
+    version: "0.0.37"
   html5lib:
     description: html5lib
     source: hosted
@@ -73,7 +70,7 @@ packages:
   route_hierarchical:
     description: route_hierarchical
     source: hosted
-    version: "0.4.15"
+    version: "0.4.18"
   shadow_dom:
     description: shadow_dom
     source: hosted

test/core/core_directive_spec.dart

@@ -67,6 +67,29 @@ void main() {
         'in Bad2Component');
       });
     });
+
+    describe("Inheritance", () {
+      var element;
+      var nodeAttrs;
+
+      beforeEachModule((Module module) {
+        module..type(Sub)..type(Base);
+      });
+
+      it("should extract attr map from annotated component which inherits other component", (DirectiveMap directives) {
+        var annotations = directives.annotationsFor(Sub);
+        expect(annotations.length).toEqual(1);
+        expect(annotations[0] is Directive).toBeTruthy();
+
+        Directive annotation = annotations[0];
+        expect(annotation.selector).toEqual('[sub]');
+        expect(annotation.map).toEqual({
+          "foo": "=>foo",
+          "bar": "=>bar",
+          "baz": "=>baz"
+        });
+      });
+    });
   });
 }
 
@@ -141,3 +164,18 @@ class Bad2Component {
   @NgOneWay('foo')
   set foo(val) {}
 }
+
+@Decorator(selector: '[sub]')
+class Sub extends Base {
+  @NgOneWay('bar')
+  String bar;
+}
+
+class Base {
+  @NgOneWay('baz')
+  String baz;
+
+  @NgOneWay('foo')
+  String foo;
+}
+

test/core/registry_spec.dart

@@ -61,4 +61,4 @@ class MyAnnotation {
 }
 
 @MyAnnotation('A') @MyAnnotation('B') class A1 {}
-@MyAnnotation('A') class A2 {}
+@MyAnnotation('A') class A2 {}

test/tools/transformer/expression_generator_spec.dart

@@ -91,6 +91,39 @@ main() {
           symbols: []);
     });
 
+    it('should generate expressions for variables found in superclass', () {
+      return generates(phases,
+      inputs: {
+          'a|web/main.dart': '''
+                import 'package:angular/angular.dart';
+
+                @NgComponent(
+                    templateUrl: 'lib/foo.html',
+                    selector: 'my-component')
+                class FooComponent extends BarComponent {
+                  @NgAttr('foo')
+                  var foo;
+                }
+
+                class BarComponent {
+                  @NgAttr('bar')
+                  var bar;
+                }
+
+                main() {}
+                ''',
+          'a|lib/foo.html': '''
+                <div>{{template.foo}}</div>
+                <div>{{template.bar}}</div>''',
+          'a|web/index.html': '''
+                <script src='main.dart' type='application/dart'></script>''',
+          'angular|lib/angular.dart': libAngular,
+      },
+      getters: ['foo', 'bar', 'template'],
+      setters: ['foo', 'bar', 'template'],
+      symbols: []);
+    });
+
     it('should apply additional HTML files', () {
       htmlFiles.add('web/dummy.html');
       htmlFiles.add('/packages/b/bar.html');
@@ -186,4 +219,9 @@ library angular.core.annotation_src;
 class Component {
   const Component({String templateUrl, String selector});
 }
+
+class NgAttr {
+  final _mappingSpec = '@';
+  const NgAttr(String attrName);
+}
 ''';