feat(dart/transform): Generate ChangeDetector classes

Use the `ProtoViewDto` created by the render `Compiler` to create a
`ChangeDetectorDefinition`.

From there, generate a subclass of `AbstractChangeDetector` for each
`ChangeDetectorDefinition`.

Run some basic unit tests for the dynamic and JIT change detectors on
pre-generated change detectors.

Author: Tim Blasi

gulpfile.js

@@ -178,6 +178,12 @@ gulp.task('!build/tree.dart', function() {
 // Run a top-level `pub get` for this project.
 gulp.task('pubget.dart', pubget.dir(gulp, gulpPlugins, { dir: '.', command: DART_SDK.PUB }));
 
+// Run `pub get` only on the angular2 dir of CONFIG.dest.dart
+gulp.task('!build/pubget.angular2.dart', pubget.dir(gulp, gulpPlugins, {
+  dir: path.join(CONFIG.dest.dart, 'angular2'),
+  command: DART_SDK.PUB
+}));
+
 // Run `pub get` over CONFIG.dest.dart
 gulp.task('build/pubspec.dart', pubget.subDir(gulp, gulpPlugins, {
   dir: CONFIG.dest.dart,
@@ -588,6 +594,8 @@ gulp.task('build/packages.dart', function(done) {
   runSequence(
     'build/tree.dart',
     // Run after 'build/tree.dart' because broccoli clears the dist/dart folder
+    '!build/pubget.angular2.dart',
+    '!build/change_detect.dart',
     'build/pure-packages.dart',
     'build/format.dart',
     done);
@@ -811,6 +819,34 @@ gulp.task('clean', ['build/clean.tools', 'build/clean.js', 'build/clean.dart', '
 
 gulp.task('build', ['build.js', 'build.dart']);
 
+// ------------
+// change detection codegen
+
+
+gulp.task('build.change_detect.dart', function(done) {
+  return runSequence('build/packages.dart', '!build/pubget.angular2.dart',
+                     '!build/change_detect.dart', done);
+});
+
+gulp.task('!build/change_detect.dart', function(done) {
+  var fs = require('fs');
+  var changeDetectDir = path.join(CONFIG.dest.dart, 'angular2/test/change_detection/');
+  var srcDir = path.join(changeDetectDir, 'generator');
+  var destDir = path.join(changeDetectDir, 'generated');
+
+  var dartStream = fs.createWriteStream(path.join(destDir, 'simple_watch_classes.dart'));
+  var genMain = path.join(srcDir, 'gen_change_detectors.dart');
+  var proc = spawn(DART_SDK.VM, [genMain], { stdio:['ignore', 'pipe', 'inherit'] });
+  proc.on('error', function(code) {
+    done(new Error('Failed while generating change detector classes. Please run manually: ' +
+                   DART_SDK.VM + ' ' + dartArgs.join(' ')));
+  });
+  proc.on('close', function() {
+    dartStream.close();
+    done();
+  });
+  proc.stdout.pipe(dartStream);
+});
 
 // ------------
 // angular material testing rules

modules/angular2/src/change_detection/change_detection_jit_generator.ts

@@ -27,6 +27,10 @@ import {
  * The code generator takes a list of proto records and creates a function/class
  * that "emulates" what the developer would write by hand to implement the same
  * kind of behaviour.
+ *
+ * This code should be kept in sync with the Dart transformer's
+ * `angular2.transform.template_compiler.change_detector_codegen` library. If you make updates
+ * here, please make equivalent changes there.
 */
 var ABSTRACT_CHANGE_DETECTOR = "AbstractChangeDetector";
 var UTIL = "ChangeDetectionUtil";

modules/angular2/src/change_detection/pregen_proto_change_detector.dart

@@ -0,0 +1,65 @@
+library angular2.src.change_detection.pregen_proto_change_detector;
+
+import 'package:angular2/src/change_detection/coalesce.dart';
+import 'package:angular2/src/change_detection/directive_record.dart';
+import 'package:angular2/src/change_detection/interfaces.dart';
+import 'package:angular2/src/change_detection/pipes/pipe_registry.dart';
+import 'package:angular2/src/change_detection/proto_change_detector.dart';
+import 'package:angular2/src/change_detection/proto_record.dart';
+
+export 'dart:core' show List;
+export 'package:angular2/src/change_detection/abstract_change_detector.dart'
+    show AbstractChangeDetector;
+export 'package:angular2/src/change_detection/directive_record.dart'
+    show DirectiveIndex, DirectiveRecord;
+export 'package:angular2/src/change_detection/interfaces.dart'
+    show ChangeDetector, ChangeDetectorDefinition, ProtoChangeDetector;
+export 'package:angular2/src/change_detection/pipes/pipe_registry.dart'
+    show PipeRegistry;
+export 'package:angular2/src/change_detection/proto_record.dart'
+    show ProtoRecord;
+export 'package:angular2/src/change_detection/change_detection_util.dart'
+    show ChangeDetectionUtil;
+export 'package:angular2/src/facade/lang.dart' show looseIdentical;
+
+typedef ChangeDetector InstantiateMethod(dynamic dispatcher,
+    PipeRegistry registry, List<ProtoRecord> protoRecords,
+    List<DirectiveRecord> directiveRecords);
+
+/// Implementation of [ProtoChangeDetector] for use by pre-generated change
+/// detectors in Angular 2 Dart.
+/// Classes generated by the `TemplateCompiler` use this. The `export`s above
+/// allow the generated code to `import` a single library and get all
+/// dependencies.
+class PregenProtoChangeDetector extends ProtoChangeDetector {
+  /// The [ChangeDetectorDefinition#id]. Strictly informational.
+  final String id;
+
+  /// Closure used to generate an actual [ChangeDetector].
+  final InstantiateMethod _instantiateMethod;
+
+  // [ChangeDetector] dependencies.
+  final PipeRegistry _pipeRegistry;
+  final List<ProtoRecord> _protoRecords;
+  final List<DirectiveRecord> _directiveRecords;
+
+  /// Internal ctor.
+  PregenProtoChangeDetector._(this.id, this._instantiateMethod,
+      this._pipeRegistry, this._protoRecords, this._directiveRecords);
+
+  factory PregenProtoChangeDetector(InstantiateMethod instantiateMethod,
+      PipeRegistry registry, ChangeDetectorDefinition def) {
+    // TODO(kegluneq): Pre-generate these (#2067).
+    var recordBuilder = new ProtoRecordBuilder();
+    def.bindingRecords.forEach((b) {
+      recordBuilder.add(b, def.variableNames);
+    });
+    var protoRecords = coalesce(recordBuilder.records);
+    return new PregenProtoChangeDetector._(def.id, instantiateMethod, registry,
+        protoRecords, def.directiveRecords);
+  }
+
+  @override
+  instantiate(dynamic dispatcher) => _instantiateMethod(
+      dispatcher, _pipeRegistry, _protoRecords, _directiveRecords);
+}