Initial support for an explicit plugin list

pkg/analyzer/test/src/task/options_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.test.src.task.options_test;
 
 import 'dart:mirrors';
 
 import 'package:analyzer/analyzer.dart';
 import 'package:analyzer/source/analysis_options_provider.dart';
@@ skipping 109 matching lines @@
 analyzer:
   exclude:
     - foo/bar.dart
     - 'test/**'
 ''');
 
     List<String> excludes = analysisOptions.excludePatterns;
     expect(excludes, unorderedEquals(['foo/bar.dart', 'test/**']));
   }
 
+  test_configure_plugins_list() {
+    configureContext('''
+analyzer:
+  plugins:
+    - angular2
+    - intl
+''');
+
+    List<String> names = analysisOptions.enabledPluginNames;
+    expect(names, ['angular2', 'intl']);
+  }
+
+  test_configure_plugins_map() {
+    configureContext('''
+analyzer:
+  plugins:
+    angular2:
+      enabled: true
+''');
+
+    List<String> names = analysisOptions.enabledPluginNames;
+    expect(names, ['angular2']);
+  }
+
+  test_configure_plugins_string() {
+    configureContext('''
+analyzer:
+  plugins:
+    angular2
+''');
+
+    List<String> names = analysisOptions.enabledPluginNames;
+    expect(names, ['angular2']);
+  }
+
   test_configure_strong_mode() {
     configureContext('''
 analyzer:
   strong-mode: true
 ''');
     expect(analysisOptions.strongMode, true);
   }
 
   test_configure_strong_mode_bad_value() {
     configureContext('''
@@ skipping 419 matching lines @@
     var options = optionsProvider.getOptionsFromString(source);
     var errors = validator.validate(options);
     expect(errors.map((AnalysisError e) => e.errorCode),
         unorderedEquals(expected));
   }
 }
 
 class TestRule extends LintRule {
   TestRule() : super(name: 'fantastic_test_rule');
 }