feat(dart/transform): Detect annotations which extend Injectable or Template.

Create a method that recursively walks imports from an entry point and
determines where classes are registered.

Use this information to determine if a particular annotation implements or
extends Injectable or Template.

modules/angular2/src/transform/common/classdef_parser.dart

@@ -0,0 +1,86 @@
+library angular2.src.transform.common.classdef_parser;
+
+import 'dart:async';
+
+import 'package:analyzer/analyzer.dart';
+import 'package:angular2/src/transform/common/asset_reader.dart';
+import 'package:angular2/src/transform/common/logging.dart';
+import 'package:barback/barback.dart';
+import 'package:code_transformers/assets.dart';
+
+/// Creates a mapping of [AssetId]s to the [ClassDeclaration]s which they
+/// define.
+Future<Map<AssetId, List<ClassDeclaration>>> createTypeMap(
+    AssetReader reader, AssetId id) {
+  return _recurse(reader, id);
+}
+
+Future<Map<AssetId, List<ClassDeclaration>>> _recurse(
+    AssetReader reader, AssetId id,
+    [_ClassDefVisitor visitor, Set<AssetId> seen]) async {
+  if (seen == null) seen = new Set<AssetId>();
+  if (visitor == null) visitor = new _ClassDefVisitor();
+
+  if (seen.contains(id)) return visitor.result;
+  seen.add(id);
+
+  var hasAsset = await reader.hasInput(id);
+  if (!hasAsset) return visitor.result;
+
+  var code = await reader.readAsString(id);
+  visitor.current = id;
+  parseCompilationUnit(code,
+      name: id.path,
+      parseFunctionBodies: false,
+      suppressErrors: true).accept(visitor);
+  var toWait = [];
+  visitor.dependencies[id]
+      .map((node) => stringLiteralToString(node.uri))
+      .where(_isNotDartImport)
+      .forEach((uri) {
+    var nodeId = uriToAssetId(id, uri, logger, null);
+    toWait.add(_recurse(reader, nodeId, visitor, seen));
+  });
+
+  await Future.wait(toWait);
+  return visitor.result;
+}
+
+bool _isNotDartImport(String uri) => !uri.startsWith('dart:');
+
+class _ClassDefVisitor extends Object with RecursiveAstVisitor<Object> {
+  final Map<AssetId, List<ClassDeclaration>> result = {};
+  final Map<AssetId, List<NamespaceDirective>> dependencies = {};
+  List<ClassDeclaration> _currentClass;
+  List<NamespaceDirective> _currentDependencies;
+
+  void set current(AssetId val) {
+    _currentDependencies = dependencies.putIfAbsent(val, () => []);
+    _currentClass = result.putIfAbsent(val, () => []);
+  }
+
+  // TODO(kegluneq): Handle `part` directives.
+  @override
+  Object visitPartDirective(PartDirective node) => null;
+
+  @override
+  Object visitImportDirective(ImportDirective node) {
+    _currentDependencies.add(node);
+    return null;
+  }
+
+  @override
+  Object visitExportDirective(ExportDirective node) {
+    _currentDependencies.add(node);
+    return null;
+  }
+
+  @override
+  Object visitFunctionDeclaration(FunctionDeclaration node) => null;
+
+  @override
+  Object visitClassDeclaration(ClassDeclaration node) {
+    _currentClass.add(node);
+    return null;
+  }
+}

modules/angular2/src/transform/directive_processor/rewriter.dart

@@ -4,6 +4,7 @@ import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/src/generated/java_core.dart';
 import 'package:angular2/src/transform/common/logging.dart';
 import 'package:angular2/src/transform/common/names.dart';
+import 'package:barback/barback.dart' show AssetId;
 import 'package:path/path.dart' as path;
 
 import 'visitors.dart';
@@ -15,11 +16,12 @@ import 'visitors.dart';
 /// If no Angular 2 `Directive`s are found in [code], returns the empty
 /// string unless [forceGenerate] is true, in which case an empty ngDeps
 /// file is created.
-String createNgDeps(String code, String path) {
+String createNgDeps(String code, String path,
+    Map<AssetId, List<ClassDeclaration>> assetClasses) {
   // TODO(kegluneq): Shortcut if we can determine that there are no
   // [Directive]s present, taking into account `export`s.
   var writer = new PrintStringWriter();
-  var visitor = new CreateNgDepsVisitor(writer, path);
+  var visitor = new CreateNgDepsVisitor(writer, path, assetClasses);
   parseCompilationUnit(code, name: path).accept(visitor);
   return '$writer';
 }
@@ -28,7 +30,7 @@ String createNgDeps(String code, String path) {
 /// associated .ng_deps.dart file.
 class CreateNgDepsVisitor extends Object with SimpleAstVisitor<Object> {
   final PrintWriter writer;
-  final _Tester _tester = const _Tester();
+  final _Tester _tester;
   bool _foundNgDirectives = false;
   bool _wroteImport = false;
   final ToSourceVisitor _copyVisitor;
@@ -39,12 +41,14 @@ class CreateNgDepsVisitor extends Object with SimpleAstVisitor<Object> {
   /// The path to the file which we are parsing.
   final String importPath;
 
-  CreateNgDepsVisitor(PrintWriter writer, this.importPath)
+  CreateNgDepsVisitor(PrintWriter writer, this.importPath,
+      Map<AssetId, List<ClassDeclaration>> assetClasses)
       : writer = writer,
         _copyVisitor = new ToSourceVisitor(writer),
         _factoryVisitor = new FactoryTransformVisitor(writer),
         _paramsVisitor = new ParameterTransformVisitor(writer),
-        _metaVisitor = new AnnotationsTransformVisitor(writer);
+        _metaVisitor = new AnnotationsTransformVisitor(writer),
+        _tester = new _Tester(assetClasses);
 
   void _visitNodeListWithSeparator(NodeList<AstNode> list, String separator) {
     if (list == null) return;
@@ -136,7 +140,7 @@ class CreateNgDepsVisitor extends Object with SimpleAstVisitor<Object> {
 
   @override
   Object visitClassDeclaration(ClassDeclaration node) {
-    var shouldProcess = node.metadata.any(_tester._isDirective);
+    var shouldProcess = node.metadata.any(_tester._shouldKeepMeta);
 
     if (shouldProcess) {
       var ctor = _getCtor(node);
@@ -199,15 +203,40 @@ class CreateNgDepsVisitor extends Object with SimpleAstVisitor<Object> {
   Object visitSimpleIdentifier(SimpleIdentifier node) => _nodeToSource(node);
 }
 
-class _Tester {
-  const _Tester();
+const annotationNamesToKeep = const ['Injectable', 'Template'];
 
-  bool _isDirective(Annotation meta) {
-    var metaName = meta.name.toString();
-    return metaName == 'Component' ||
-        metaName == 'Decorator' ||
-        metaName == 'Injectable' ||
-        metaName == 'View' ||
-        metaName == 'Viewport';
+class _Tester {
+  final Map<String, ClassDeclaration> _classesByName;
+
+  _Tester(Map<AssetId, List<ClassDeclaration>> assetClasses)
+      : _classesByName = new Map.fromIterables(assetClasses.values
+              .expand((classes) => classes.map((c) => c.name.toString())),
+          assetClasses.values.expand((list) => list));
+
+  bool _shouldKeepMeta(Annotation meta) =>
+      _shouldKeepClass(_classesByName[meta.name.name]);
+
+  bool _shouldKeepClass(ClassDeclaration next) {
+    while (next != null) {
+      if (annotationNamesToKeep.contains(next.name.name)) return true;
+
+      // Check classes that this class implements.
+      if (next.implementsClause != null) {
+        for (var interface in next.implementsClause.interfaces) {
+          if (_shouldKeepClass(_classesByName[interface.name.name])) {
+            return true;
+          }
+        }
+      }
+
+      // Check the class that this class extends.
+      if (next.extendsClause != null && next.extendsClause.superclass != null) {
+        next = _classesByName[next.extendsClause.superclass.name.name];
+      } else {
+        break;
+      }
+    }
+
+    return false;
   }
 }

modules/angular2/src/transform/directive_processor/transformer.dart

@@ -2,6 +2,8 @@ library angular2.transform.directive_processor.transformer;
 
 import 'dart:async';
 
+import 'package:angular2/src/transform/common/asset_reader.dart';
+import 'package:angular2/src/transform/common/classdef_parser.dart';
 import 'package:angular2/src/transform/common/logging.dart' as log;
 import 'package:angular2/src/transform/common/names.dart';
 import 'package:angular2/src/transform/common/options.dart';
@@ -32,8 +34,10 @@ class DirectiveProcessor extends Transformer {
 
     try {
       var asset = transform.primaryInput;
+      var reader = new AssetReader.fromTransform(transform);
+      var defMap = await createTypeMap(reader, asset.id);
       var assetCode = await asset.readAsString();
-      var ngDepsSrc = createNgDeps(assetCode, asset.id.path);
+      var ngDepsSrc = createNgDeps(assetCode, asset.id.path, defMap);
       if (ngDepsSrc != null && ngDepsSrc.isNotEmpty) {
         var ngDepsAssetId =
             transform.primaryInput.id.changeExtension(DEPS_EXTENSION);