feature(dart/transform): Inject `initReflector` at @AngularEntrypoint

Detect the `@AngularEntrypoint` annotations on methods and/or
functions and add a call to `initReflector` there.

See #4865

modules_dart/payload/hello_world/web/index.dart

@@ -1,9 +1,10 @@
 library hello_world.index;
 
-import "package:angular2/bootstrap.dart" show bootstrap;
+import "package:angular2/bootstrap.dart" show AngularEntrypoint, bootstrap;
 import "package:angular2/angular2.dart"
     show Component, Directive, ElementRef, Injectable, Renderer;
 
+@AngularEntrypoint("Hello World Entrypoint")
 main() {
   bootstrap(HelloCmp);
 }

modules_dart/transform/lib/src/transform/common/annotation_matcher.dart

@@ -22,7 +22,7 @@ const _INJECTABLES = const [
 
 const _DIRECTIVES = const [
   const ClassDescriptor(
-      'Directive', 'package:angular2/src/core/metadatada/directive.dart',
+      'Directive', 'package:angular2/src/core/metadata/directive.dart',
       superClass: 'Injectable'),
   const ClassDescriptor('Directive', 'package:angular2/src/core/metadata.dart',
       superClass: 'Injectable'),
@@ -57,6 +57,19 @@ const _VIEWS = const [
   const ClassDescriptor('View', 'package:angular2/src/core/metadata.dart'),
 ];
 
+const _ENTRYPOINTS = const [
+  const ClassDescriptor('AngularEntrypoint', 'package:angular2/angular2.dart'),
+  const ClassDescriptor('AngularEntrypoint', 'package:angular2/bootstrap.dart'),
+  const ClassDescriptor(
+      'AngularEntrypoint', 'package:angular2/bootstrap_static.dart'),
+  const ClassDescriptor(
+      'AngularEntrypoint', 'package:angular2/platform/browser.dart'),
+  const ClassDescriptor(
+      'AngularEntrypoint', 'package:angular2/platform/browser_static.dart'),
+  const ClassDescriptor(
+      'AngularEntrypoint', 'package:angular2/src/core/angular_entrypoint.dart'),
+];
+
 /// Checks if a given [Annotation] matches any of the given
 /// [ClassDescriptors].
 class AnnotationMatcher extends ClassMatcherBase {
@@ -67,7 +80,8 @@ class AnnotationMatcher extends ClassMatcherBase {
       ..addAll(_COMPONENTS)
       ..addAll(_DIRECTIVES)
       ..addAll(_INJECTABLES)
-      ..addAll(_VIEWS));
+      ..addAll(_VIEWS)
+      ..addAll(_ENTRYPOINTS));
   }
 
   bool _implementsWithWarning(Annotation annotation, AssetId assetId,
@@ -94,4 +108,8 @@ class AnnotationMatcher extends ClassMatcherBase {
   /// Checks if an [Annotation] node implements [View].
   bool isView(Annotation annotation, AssetId assetId) =>
       _implementsWithWarning(annotation, assetId, _VIEWS);
+
+  /// Checks if an [Annotation] node implements [AngularEntrypoint]
+  bool isEntrypoint(Annotation annotation, AssetId assetId) =>
+      _implementsWithWarning(annotation, assetId, _ENTRYPOINTS);
 }

modules_dart/transform/lib/src/transform/reflection_remover/entrypoint_matcher.dart

@@ -0,0 +1,59 @@
+library angular2.transform.reflection_remover.entrypoint_matcher;
+
+import 'package:analyzer/analyzer.dart';
+import 'package:barback/barback.dart';
+
+import 'package:angular2/src/transform/common/annotation_matcher.dart';
+import 'package:angular2/src/transform/common/naive_eval.dart';
+
+/// Determines if a [FunctionDeclaration] or [MethodDeclaration] is an
+/// `AngularEntrypoint`.
+class EntrypointMatcher {
+  final AssetId _assetId;
+  final AnnotationMatcher _annotationMatcher;
+
+  EntrypointMatcher(this._assetId, this._annotationMatcher) {
+    if (_assetId == null) {
+      throw new ArgumentError.notNull('AssetId');
+    }
+    if (_annotationMatcher == null) {
+      throw new ArgumentError.notNull('AnnotationMatcher');
+    }
+  }
+
+  bool isEntrypoint(AnnotatedNode node) {
+    if (node == null ||
+        (node is! FunctionDeclaration && node is! MethodDeclaration)) {
+      return false;
+    }
+    return node.metadata
+        .any((a) => _annotationMatcher.isEntrypoint(a, _assetId));
+  }
+
+  /// Gets the name assigned to the `AngularEntrypoint`.
+  ///
+  /// This method assumes the name is the first argument to `AngularEntrypoint`;
+  String getName(AnnotatedNode node) {
+    final annotation = node.metadata.firstWhere(
+        (a) => _annotationMatcher.isEntrypoint(a, _assetId),
+        orElse: () => null);
+    if (annotation == null) return null;
+    if (annotation.arguments == null ||
+        annotation.arguments.arguments == null ||
+        annotation.arguments.arguments.isEmpty) {
+      return _defaultEntrypointName;
+    }
+    final entryPointName = naiveEval(annotation.arguments.arguments.first);
+    if (entryPointName == NOT_A_CONSTANT) {
+      throw new ArgumentError(
+          'Could not evaluate "${node}" as parameter to @AngularEntrypoint');
+    }
+    if (entryPointName is! String) {
+      throw new ArgumentError('Unexpected type "${entryPointName.runtimeType}" '
+          'as first parameter to @AngularEntrypoint');
+    }
+    return entryPointName;
+  }
+}
+
+const _defaultEntrypointName = "(no name provided)";

modules_dart/transform/lib/src/transform/reflection_remover/remove_reflection_capabilities.dart

@@ -2,11 +2,14 @@ library angular2.transform.reflection_remover.remove_reflection_capabilities;
 
 import 'dart:async';
 import 'package:analyzer/analyzer.dart';
-import 'package:angular2/src/transform/common/asset_reader.dart';
-import 'package:angular2/src/transform/common/mirror_mode.dart';
 import 'package:barback/barback.dart';
 
+import 'package:angular2/src/transform/common/annotation_matcher.dart';
+import 'package:angular2/src/transform/common/asset_reader.dart';
+import 'package:angular2/src/transform/common/mirror_mode.dart';
+
 import 'codegen.dart';
+import 'entrypoint_matcher.dart';
 import 'rewriter.dart';
 
 /// Finds the call to the Angular2 `ReflectionCapabilities` constructor
@@ -15,14 +18,15 @@ import 'rewriter.dart';
 ///
 /// This only searches the code in `reflectionEntryPoint`, not `part`s,
 /// `import`s, `export`s, etc.
-Future<String> removeReflectionCapabilities(
-    AssetReader reader, AssetId reflectionEntryPoint,
+Future<String> removeReflectionCapabilities(AssetReader reader,
+    AssetId reflectionEntryPoint, AnnotationMatcher annotationMatcher,
     {MirrorMode mirrorMode: MirrorMode.none,
     bool writeStaticInit: true}) async {
   var code = await reader.readAsString(reflectionEntryPoint);
 
   var codegen = new Codegen(reflectionEntryPoint);
   return new Rewriter(code, codegen,
+          new EntrypointMatcher(reflectionEntryPoint, annotationMatcher),
           mirrorMode: mirrorMode, writeStaticInit: writeStaticInit)
       .rewrite(parseCompilationUnit(code, name: reflectionEntryPoint.path));
 }

modules_dart/transform/lib/src/transform/reflection_remover/rewriter.dart

@@ -1,31 +1,43 @@
 library angular2.transform.reflection_remover.rewriter;
 
 import 'package:analyzer/src/generated/ast.dart';
+import 'package:path/path.dart' as path;
+
 import 'package:angular2/src/transform/common/logging.dart';
 import 'package:angular2/src/transform/common/mirror_matcher.dart';
 import 'package:angular2/src/transform/common/mirror_mode.dart';
 import 'package:angular2/src/transform/common/names.dart';
-import 'package:path/path.dart' as path;
 
 import 'codegen.dart';
+import 'entrypoint_matcher.dart';
 
 class Rewriter {
   final String _code;
   final Codegen _codegen;
+  final EntrypointMatcher _entrypointMatcher;
   final MirrorMatcher _mirrorMatcher;
   final MirrorMode _mirrorMode;
   final bool _writeStaticInit;
 
-  Rewriter(this._code, this._codegen,
+  Rewriter(this._code, this._codegen, this._entrypointMatcher,
       {MirrorMatcher mirrorMatcher,
       MirrorMode mirrorMode: MirrorMode.none,
       bool writeStaticInit: true})
       : _mirrorMode = mirrorMode,
         _writeStaticInit = writeStaticInit,
         _mirrorMatcher =
-            mirrorMatcher == null ? const MirrorMatcher() : mirrorMatcher;
+            mirrorMatcher == null ? const MirrorMatcher() : mirrorMatcher {
+    if (_codegen == null) {
+      throw new ArgumentError.notNull('Codegen');
+    }
+    if (_entrypointMatcher == null) {
+      throw new ArgumentError.notNull('EntrypointMatcher');
+    }
+  }
 
-  /// Rewrites the provided code removing imports of the
+  /// Rewrites the provided code to remove dart:mirrors.
+  ///
+  /// Specifically, removes imports of the
   /// {@link ReflectionCapabilities} library and instantiations of
   /// {@link ReflectionCapabilities}, as detected by the (potentially) provided
   /// {@link MirrorMatcher}.
@@ -51,7 +63,7 @@ class Rewriter {
 class _RewriterVisitor extends Object with RecursiveAstVisitor<Object> {
   final Rewriter _rewriter;
   final buf = new StringBuffer();
-  final reflectionCapabilityAssignments = [];
+  final reflectionCapabilityAssignments = <AssignmentExpression>[];
 
   int _currentIndex = 0;
   bool _setupAdded = false;
@@ -105,6 +117,45 @@ class _RewriterVisitor extends Object with RecursiveAstVisitor<Object> {
     return super.visitMethodInvocation(node);
   }
 
+  @override
+  Object visitMethodDeclaration(MethodDeclaration node) {
+    if (_rewriter._entrypointMatcher.isEntrypoint(node)) {
+      if (_rewriter._writeStaticInit) {
+        _rewriteEntrypointFunctionBody(node.body);
+      }
+    }
+    return super.visitMethodDeclaration(node);
+  }
+
+  @override
+  Object visitFunctionDeclaration(FunctionDeclaration node) {
+    if (_rewriter._entrypointMatcher.isEntrypoint(node)) {
+      if (_rewriter._writeStaticInit) {
+        _rewriteEntrypointFunctionBody(node.functionExpression.body);
+      }
+    }
+    return super.visitFunctionDeclaration(node);
+  }
+
+  void _rewriteEntrypointFunctionBody(FunctionBody node) {
+    if (node is BlockFunctionBody) {
+      final insertOffset = node.block.leftBracket.end;
+      buf.write(_rewriter._code.substring(_currentIndex, insertOffset));
+      buf.write(_getStaticReflectorInitBlock());
+      _currentIndex = insertOffset;
+    } else if (node is ExpressionFunctionBody) {
+      // TODO(kegluneq): Add support, see issue #5474.
+      throw new ArgumentError(
+          'Arrow syntax is not currently supported as `@AngularEntrypoint`s');
+    } else if (node is NativeFunctionBody) {
+      throw new ArgumentError('Native functions and methods are not supported '
+          'as `@AngularEntrypoint`s');
+    } else if (node is EmptyFunctionBody) {
+      throw new ArgumentError('Empty functions and methods are not supported '
+          'as `@AngularEntrypoint`s');
+    }
+  }
+
   String outputRewrittenCode() {
     if (_currentIndex < _rewriter._code.length) {
       buf.write(_rewriter._code.substring(_currentIndex));

modules_dart/transform/lib/src/transform/reflection_remover/transformer.dart

@@ -52,8 +52,11 @@ class ReflectionRemover extends Transformer implements LazyTransformer {
       }
 
       var transformedCode = await removeReflectionCapabilities(
-          new AssetReader.fromTransform(transform), primaryId,
-          mirrorMode: mirrorMode, writeStaticInit: writeStaticInit);
+          new AssetReader.fromTransform(transform),
+          primaryId,
+          options.annotationMatcher,
+          mirrorMode: mirrorMode,
+          writeStaticInit: writeStaticInit);
       transform.addOutput(new Asset.fromString(primaryId, transformedCode));
     }, log: transform.logger);
   }

modules_dart/transform/test/transform/reflection_remover/abstract_method_annotation_files/index.dart

@@ -0,0 +1,8 @@
+library web_foo;
+
+import 'package:angular2/bootstrap.dart';
+
+abstract class TestBootstrapper {
+  @AngularEntrypoint()
+  void testBootstrap();
+}

modules_dart/transform/test/transform/reflection_remover/all_tests.dart

@@ -1,62 +1,123 @@
 library angular2.test.transform.reflection_remover;
 
 import 'package:analyzer/analyzer.dart';
-import 'package:angular2/src/transform/common/mirror_mode.dart';
-import 'package:angular2/src/transform/reflection_remover/codegen.dart';
-import 'package:angular2/src/transform/reflection_remover/rewriter.dart';
 import 'package:barback/barback.dart';
 import 'package:guinness/guinness.dart';
 
-import 'reflection_remover_files/expected/index.dart' as expected;
-import 'debug_mirrors_files/expected/index.dart' as debug_mirrors;
-import 'log_mirrors_files/expected/index.dart' as log_mirrors;
-import 'verbose_files/expected/index.dart' as verbose_mirrors;
-import 'bootstrap_files/expected/index.dart' as bootstrap_expected;
+import 'package:angular2/src/transform/common/annotation_matcher.dart';
+import 'package:angular2/src/transform/common/mirror_mode.dart';
+import 'package:angular2/src/transform/reflection_remover/codegen.dart';
+import 'package:angular2/src/transform/reflection_remover/entrypoint_matcher.dart';
+import 'package:angular2/src/transform/reflection_remover/rewriter.dart';
+
 import '../common/read_file.dart';
+import 'bootstrap_files/expected/index.dart' as bootstrap_expected;
+import 'debug_mirrors_files/expected/index.dart' as debug_mirrors;
+import 'function_annotation_files/expected/index.dart'
+    as func_annotation_expected;
+import 'log_mirrors_files/expected/index.dart' as log_mirrors;
+import 'method_annotation_files/expected/index.dart'
+    as method_annotation_expected;
+import 'reflection_remover_files/expected/index.dart' as expected;
+import 'verbose_files/expected/index.dart' as verbose_mirrors;
 
 main() => allTests();
 
 void allTests() {
-  var assetId = new AssetId('a', 'web/index.dart');
-  var codegen = new Codegen(assetId);
-  var code = readFile('reflection_remover/index.dart').replaceAll('\r\n', '\n');
-  var bootstrapCode = readFile('reflection_remover/bootstrap_files/index.dart')
-      .replaceAll('\r\n', '\n');
+  var entrypointMatcher, assetId, codegen, code;
+
+  beforeEach(() {
+    assetId = new AssetId('a', 'web/index.dart');
+    codegen = new Codegen(assetId);
+    code = readFile('reflection_remover/index.dart').replaceAll('\r\n', '\n');
+    entrypointMatcher = new EntrypointMatcher(assetId, new AnnotationMatcher());
+  });
 
   it(
       'should remove uses of mirrors & '
       'insert calls to generated code by default.', () {
-    var output =
-        new Rewriter(code, codegen).rewrite(parseCompilationUnit(code));
+    var output = new Rewriter(code, codegen, entrypointMatcher)
+        .rewrite(parseCompilationUnit(code));
     expect(output).toEqual(expected.code);
   });
 
   it(
       'should replace uses of mirrors with the debug implementation & '
       'insert calls to generated code in `MirrorMode.debug`.', () {
-    var output = new Rewriter(code, codegen, mirrorMode: MirrorMode.debug)
-        .rewrite(parseCompilationUnit(code));
+    var output = new Rewriter(code, codegen, entrypointMatcher,
+        mirrorMode: MirrorMode.debug).rewrite(parseCompilationUnit(code));
     expect(output).toEqual(debug_mirrors.code);
   });
 
   it(
       'should replace uses of mirrors with the verbose implementation '
       'in `MirrorMode.verbose`.', () {
-    var output = new Rewriter(code, codegen, mirrorMode: MirrorMode.verbose)
-        .rewrite(parseCompilationUnit(code));
+    var output = new Rewriter(code, codegen, entrypointMatcher,
+        mirrorMode: MirrorMode.verbose).rewrite(parseCompilationUnit(code));
     expect(output).toEqual(verbose_mirrors.code);
   });
 
   it('should not initialize the reflector when `writeStaticInit` is `false`.',
       () {
-    var output = new Rewriter(code, codegen, writeStaticInit: false)
-        .rewrite(parseCompilationUnit(code));
+    var output = new Rewriter(code, codegen, entrypointMatcher,
+        writeStaticInit: false).rewrite(parseCompilationUnit(code));
     expect(output).toEqual(log_mirrors.code);
   });
 
   it('should rewrite bootstrap.', () {
-    var output = new Rewriter(bootstrapCode, codegen, writeStaticInit: true)
-        .rewrite(parseCompilationUnit(bootstrapCode));
+    final bootstrapCode =
+        readFile('reflection_remover/bootstrap_files/index.dart')
+            .replaceAll('\r\n', '\n');
+    var output = new Rewriter(bootstrapCode, codegen, entrypointMatcher,
+        writeStaticInit: true).rewrite(parseCompilationUnit(bootstrapCode));
     expect(output).toEqual(bootstrap_expected.code);
   });
+
+  describe('AngularEntrypoint annotation', () {
+    it('should add a call to `initReflector` at the beginning of the function',
+        () {
+      code = readFile('reflection_remover/function_annotation_files/index.dart')
+          .replaceAll('\r\n', '\n');
+      final output = new Rewriter(code, codegen, entrypointMatcher)
+          .rewrite(parseCompilationUnit(code));
+      expect(output).toEqual(func_annotation_expected.code);
+    });
+
+    it('should `throw` for entrypoints implemented as arrow functions', () {
+      code = readFile('reflection_remover/arrow_annotation_files/index.dart')
+          .replaceAll('\r\n', '\n');
+      expect(() {
+        new Rewriter(code, codegen, entrypointMatcher)
+            .rewrite(parseCompilationUnit(code));
+      }).toThrowWith(anInstanceOf: ArgumentError);
+    });
+
+    it('should `throw` for native functions annotated as entry points', () {
+      code = readFile('reflection_remover/native_annotation_files/index.dart')
+          .replaceAll('\r\n', '\n');
+      expect(() {
+        new Rewriter(code, codegen, entrypointMatcher)
+            .rewrite(parseCompilationUnit(code));
+      }).toThrowWith(anInstanceOf: ArgumentError);
+    });
+
+    it('should `throw` for abstract functions annotated as entry points', () {
+      code = readFile(
+              'reflection_remover/abstract_method_annotation_files/index.dart')
+          .replaceAll('\r\n', '\n');
+      expect(() {
+        new Rewriter(code, codegen, entrypointMatcher)
+            .rewrite(parseCompilationUnit(code));
+      }).toThrowWith(anInstanceOf: ArgumentError);
+    });
+
+    it('should add a call to `initReflector` at the beginning of the method',
+        () {
+      code = readFile('reflection_remover/method_annotation_files/index.dart')
+          .replaceAll('\r\n', '\n');
+      final output = new Rewriter(code, codegen, entrypointMatcher)
+          .rewrite(parseCompilationUnit(code));
+      expect(output).toEqual(method_annotation_expected.code);
+    });
+  });
 }

modules_dart/transform/test/transform/reflection_remover/arrow_annotation_files/index.dart

@@ -0,0 +1,8 @@
+library web_foo;
+
+import 'package:angular2/bootstrap.dart';
+import 'package:angular2/src/core/reflection/reflection.dart';
+import 'package:angular2/src/core/reflection/reflection_capabilities.dart';
+
+@AngularEntrypoint()
+main() => bootstrap(MyComponent);

modules_dart/transform/test/transform/reflection_remover/function_annotation_files/expected/index.dart

@@ -0,0 +1,23 @@
+library angular2.test.transform.reflection_remover.function_annotation_files;
+
+// This file is intentionally formatted as a string to avoid having the
+// automatic transformer prettify it.
+//
+// This file represents transformed user code. Because this code will be
+// linked to output by a source map, we cannot change line numbers from the
+// original code and we therefore add our generated code on the same line as
+// those we are removing.
+
+const code = """
+library web_foo;
+
+import 'package:angular2/bootstrap_static.dart';import 'index.ng_deps.dart' as ngStaticInit;
+import 'package:angular2/src/core/reflection/reflection.dart';
+/*import 'package:angular2/src/core/reflection/reflection_capabilities.dart';*/
+
+@AngularEntrypoint()
+void main() {ngStaticInit.initReflector();
+  ngStaticInit.initReflector();/*reflector.reflectionCapabilities = new ReflectionCapabilities();*/
+  bootstrapStatic(MyComponent);
+}
+""";

modules_dart/transform/test/transform/reflection_remover/function_annotation_files/index.dart

@@ -0,0 +1,11 @@
+library web_foo;
+
+import 'package:angular2/bootstrap.dart';
+import 'package:angular2/src/core/reflection/reflection.dart';
+import 'package:angular2/src/core/reflection/reflection_capabilities.dart';
+
+@AngularEntrypoint()
+void main() {
+  reflector.reflectionCapabilities = new ReflectionCapabilities();
+  bootstrap(MyComponent);
+}

modules_dart/transform/test/transform/reflection_remover/method_annotation_files/expected/index.dart

@@ -0,0 +1,20 @@
+library angular2.test.transform.reflection_remover.method_annotation_files;
+
+// This file is intentionally formatted as a string to avoid having the
+// automatic transformer prettify it.
+//
+// This file represents transformed user code. Because this code will be
+// linked to output by a source map, we cannot change line numbers from the
+// original code and we therefore add our generated code on the same line as
+// those we are removing.
+
+const code = """
+library web_foo;
+
+import 'package:angular2/bootstrap_static.dart';import 'index.ng_deps.dart' as ngStaticInit;
+
+class TestBootstrapper {
+  @AngularEntrypoint("Method entrypoint")
+  void testBootstrap() {ngStaticInit.initReflector();}
+}
+""";

modules_dart/transform/test/transform/reflection_remover/method_annotation_files/index.dart

@@ -0,0 +1,8 @@
+library web_foo;
+
+import 'package:angular2/bootstrap.dart';
+
+class TestBootstrapper {
+  @AngularEntrypoint("Method entrypoint")
+  void testBootstrap() {}
+}

modules_dart/transform/test/transform/reflection_remover/native_annotation_files/index.dart

@@ -0,0 +1,8 @@
+library web_foo;
+
+import 'package:angular2/bootstrap.dart';
+import 'package:angular2/src/core/reflection/reflection.dart';
+import 'package:angular2/src/core/reflection/reflection_capabilities.dart';
+
+@AngularEntrypoint()
+main() native "MainMethod";