feat(dart/transform): Add a parser for `.ng_deps.dart` files and use.

Use the parser in `BindGenerator`
This checkin also removes types from `registerSetters` calls since they
can cause runtime failures (see #886). We will resolve this by
generating change detector classes in the future.

modules/angular2/src/transform/bind_generator/generator.dart

@@ -1,93 +1,53 @@
 library angular2.src.transform.bind_generator.generator;
 
-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:angular2/src/transform/common/visitor_mixin.dart';
+import 'dart:async';
 
-String createNgSetters(String code, String path) {
-  if (_noSettersPresent(code)) return code;
+import 'package:angular2/src/transform/common/asset_reader.dart';
+import 'package:angular2/src/transform/common/parser.dart';
+import 'package:barback/barback.dart';
 
-  var writer = new PrintStringWriter();
-  parseCompilationUnit(
-      code, name: path).accept(new CreateNgSettersVisitor(writer));
-  return writer.toString();
+import 'visitor.dart';
+
+Future<String> createNgSetters(AssetReader reader, AssetId entryPoint) async {
+  var parser = new Parser(reader);
+  NgDeps ngDeps = await parser.parse(entryPoint);
+
+  String code = ngDeps.code;
+  var setters = _generateSetters(_createBindMap(ngDeps));
+
+  if (setters.length == 0) return code;
+  var codeInjectIdx = ngDeps.registeredTypes.last.registerMethod.end;
+  return '${code.substring(0, codeInjectIdx)}'
+      '..registerSetters({${setters.join(', ')}})'
+      '${code.substring(codeInjectIdx)}';
 }
 
-bool _noSettersPresent(String code) => code.indexOf('bind') < 0;
-
-class CreateNgSettersVisitor extends ToSourceVisitor with VisitorMixin {
-  final PrintWriter writer;
-  final _ExtractSettersVisitor extractVisitor = new _ExtractSettersVisitor();
-
-  CreateNgSettersVisitor(PrintWriter writer)
-      : this.writer = writer,
-        super(writer);
-
-  @override
-  Object visitMethodInvocation(MethodInvocation node) {
-    var isRegisterType =
-        node.methodName.toString() == REGISTER_TYPE_METHOD_NAME;
-    // The first argument to a `registerType` call is the type.
-    extractVisitor.currentName = node.argumentList.arguments[0] is Identifier
-        ? node.argumentList.arguments[0]
-        : null;
-    extractVisitor.bindPieces.clear();
-
-    var retVal = super.visitMethodInvocation(node);
-    if (isRegisterType) {
-      if (extractVisitor.bindPieces.isNotEmpty) {
-        writer.print('..${REGISTER_SETTERS_METHOD_NAME}({');
-        writer.print(extractVisitor.bindPieces.join(','));
-        writer.print('})');
-      }
-    }
-    return retVal;
-  }
-
-  @override
-  Object visitMapLiteralEntry(MapLiteralEntry node) {
-    if (node.key is StringLiteral &&
-        stringLiteralToString(node.key) == 'annotations') {
-      node.value.accept(extractVisitor);
-    }
-    return super.visitMapLiteralEntry(node);
-  }
+/// Consumes the map generated by [_createBindMap] to codegen setters.
+List<String> _generateSetters(Map<String, String> bindMap) {
+  var setters = [];
+  // TODO(kegluneq): Include types for receivers. See #886.
+  bindMap.forEach((prop, type) {
+    setters.add('\'$prop\': (o, String v) => o.$prop = v');
+  });
+  return setters;
 }
 
-/// Visitor responsible for crawling the "annotations" value in a
-/// `registerType` call and generating setters from any "bind" values found.
-class _ExtractSettersVisitor extends Object
-    with RecursiveAstVisitor<Object>, VisitorMixin {
-  final List<String> bindPieces = [];
-  Identifier currentName = null;
-
-  void _extractFromMapLiteral(MapLiteral map) {
-    if (currentName == null) {
-      logger.error('Unexpected code path: `currentName` should never be null');
-    }
-    map.entries.forEach((entry) {
-      // TODO(kegluneq): Remove this restriction
-      if (entry.key is SimpleStringLiteral) {
-        var propName = entry.key.value;
-        bindPieces.add('\'${propName}\': ('
-            '${currentName} o, String value) => o.${propName} = value');
+/// Collapses all `bindProperties` in [ngDeps] into a map where the keys are
+/// the bind properties and the values are either the one and only type
+/// binding to that property or the empty string.
+Map<String, String> _createBindMap(NgDeps ngDeps) {
+  var visitor = new ExtractSettersVisitor();
+  var bindMap = {};
+  ngDeps.registeredTypes.forEach((RegisteredType t) {
+    visitor.bindMappings.clear();
+    t.annotations.accept(visitor);
+    visitor.bindMappings.forEach((String prop, _) {
+      if (bindMap.containsKey(prop)) {
+        bindMap[prop] = '';
       } else {
-        logger.error('`bind` currently only supports string literals');
+        bindMap[prop] = '${t.typeName}';
       }
     });
-  }
-
-  @override
-  Object visitNamedExpression(NamedExpression node) {
-    if (node.name.label.toString() == 'bind') {
-      // TODO(kegluneq): Remove this restriction.
-      if (node.expression is MapLiteral) {
-        _extractFromMapLiteral(node.expression);
-      }
-      return null;
-    }
-    return super.visitNamedExpression(node);
-  }
+  });
+  return bindMap;
 }

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

@@ -1,6 +1,7 @@
 library angular2.src.transform.bind_generator.transformer;
 
 import 'dart:async';
+import 'package:angular2/src/transform/common/asset_reader.dart';
 import 'package:angular2/src/transform/common/formatter.dart';
 import 'package:angular2/src/transform/common/logging.dart' as log;
 import 'package:angular2/src/transform/common/names.dart';
@@ -28,11 +29,11 @@ class BindGenerator extends Transformer {
     log.init(transform);
 
     try {
-      var assetCode = await transform.primaryInput.readAsString();
-      var assetPath = transform.primaryInput.id.path;
-      var transformedCode = createNgSetters(assetCode, assetPath);
-      transform.addOutput(new Asset.fromString(transform.primaryInput.id,
-          formatter.format(transformedCode, uri: assetPath)));
+      var id = transform.primaryInput.id;
+      var reader = new AssetReader.fromTransform(transform);
+      var transformedCode = await createNgSetters(reader, id);
+      transform.addOutput(new Asset.fromString(
+          id, formatter.format(transformedCode, uri: id.path)));
     } catch (ex, stackTrace) {
       log.logger.error('Creating ng setters failed.\n'
           'Exception: $ex\n'

modules/angular2/src/transform/bind_generator/visitor.dart

@@ -0,0 +1,39 @@
+library angular2.src.transform.bind_generator.visitor;
+
+import 'package:analyzer/analyzer.dart';
+import 'package:angular2/src/transform/common/logging.dart';
+
+/// Visitor responsible for crawling the "annotations" value in a
+/// `registerType` call and pulling out the properties of any "bind"
+/// values found.
+class ExtractSettersVisitor extends Object with RecursiveAstVisitor<Object> {
+  final Map<String, String> bindMappings = {};
+
+  void _extractFromMapLiteral(MapLiteral map) {
+    map.entries.forEach((entry) {
+      // TODO(kegluneq): Remove this restriction
+      if (entry.key is SimpleStringLiteral &&
+          entry.value is SimpleStringLiteral) {
+        bindMappings[stringLiteralToString(entry.key)] =
+            stringLiteralToString(entry.value);
+      } else {
+        logger.error('`bind` currently only supports string literals '
+            '(${entry})');
+      }
+    });
+  }
+
+  @override
+  Object visitNamedExpression(NamedExpression node) {
+    if ('${node.name.label}' == 'bind') {
+      // TODO(kegluneq): Remove this restriction.
+      if (node.expression is MapLiteral) {
+        _extractFromMapLiteral(node.expression);
+      } else {
+        logger.error('`bind` currently only supports map literals');
+      }
+      return null;
+    }
+    return super.visitNamedExpression(node);
+  }
+}

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

@@ -5,6 +5,8 @@ import 'dart:convert';
 
 import 'package:barback/barback.dart';
 
+/// A class that allows fetching code using [AssetId]s without all the
+/// additional baggage of a [Transform].
 abstract class AssetReader {
   Future<String> readAsString(AssetId id, {Encoding encoding});
   Future<bool> hasInput(AssetId id);

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

@@ -13,16 +13,22 @@ import 'registered_type.dart';
 
 export 'registered_type.dart';
 
+/// A parser that reads `.ng_deps.dart` files (represented by [AssetId]s into
+/// easier to manage [NgDeps] files.
 class Parser {
   final AssetReader _reader;
   final _ParseNgDepsVisitor _visitor = new _ParseNgDepsVisitor();
 
   Parser(AssetReader this._reader);
 
+  /// Parses the `.ng_deps.dart` file represented by `id` and all of the `
+  /// .ng_deps.dart` files that it imports.
   Future<List<NgDeps>> parseRecursive(AssetId id) async {
     return _recurse(id);
   }
 
+  /// Parses only the `.ng_deps.dart` file represented by `id`.
+  /// See also [parseRecursive].
   Future<NgDeps> parse(AssetId id) async {
     if (!(await _reader.hasInput(id))) return null;
     var ngDeps = new NgDeps(await _reader.readAsString(id));
@@ -56,6 +62,7 @@ class Parser {
   }
 }
 
+/// The contents of a `.ng_deps.dart` file.
 class NgDeps {
   final String code;
   final List<ImportDirective> imports = [];

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

@@ -3,13 +3,17 @@ library angular2.src.transform.common.registered_type;
 import 'package:analyzer/analyzer.dart';
 import 'package:angular2/src/transform/common/names.dart';
 
-/// Represents a call to `Reflector#registerType` generated by
-/// `DirectiveProcessor`.
+/// A call to `Reflector#registerType` generated by `DirectiveProcessor`.
 class RegisteredType {
+  /// The type registered by this call.
   final Identifier typeName;
+  /// The actual call to `Reflector#registerType`.
   final MethodInvocation registerMethod;
+  /// The factory method registered.
   final Expression factory;
+  /// The parameters registered.
   final Expression parameters;
+  /// The annotations registered.
   final Expression annotations;
 
   RegisteredType._(this.typeName, this.registerMethod, this.factory,

modules/angular2/test/transform/integration/basic_bind_files/expected/bar.ngDeps.dart

@@ -23,5 +23,5 @@ void setupReflection(reflector) {
             selector: '[tool-tip]', bind: const {'text': 'tool-tip'})
       ]
     })
-    ..registerSetters({'text': (ToolTip o, String value) => o.text = value});
+    ..registerSetters({'text': (o, String v) => o.text = v});
 }