Create a breadcrumb trail for analyzing of task model extensions.

pkg/analyzer/lib/src/plugin/engine_plugin.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.src.plugin.engine_plugin;
 
 import 'package:analyzer/plugin/task.dart';
 import 'package:analyzer/src/generated/engine.dart'
     show InternalAnalysisContext;
 import 'package:analyzer/src/generated/error.dart' show AnalysisError;
@@ skipping 81 matching lines @@
 
   /**
    * Initialize a newly created plugin.
    */
   EnginePlugin();
 
   /**
    * Return a list containing all of the contributed analysis error result
    * descriptors for Dart sources.
    */
+  @ExtensionPointId('DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID')
   List<TaskDescriptor> get dartErrorsForSource =>
       dartErrorsForSourceExtensionPoint.extensions;
 
   /**
    * Return a list containing all of the contributed analysis error result
    * descriptors for Dart library specific units.
    */
+  @ExtensionPointId('DART_ERRORS_FOR_UNIT_EXTENSION_POINT_ID')
   List<TaskDescriptor> get dartErrorsForUnit =>
       dartErrorsForUnitExtensionPoint.extensions;
 
   /**
    * Return a list containing all of the contributed analysis error result
    * descriptors for HTML sources.
    */
+  @ExtensionPointId('HTML_ERRORS_EXTENSION_POINT_ID')
   List<TaskDescriptor> get htmlErrors => htmlErrorsExtensionPoint.extensions;
 
   /**
    * Return a list containing all of the task descriptors that were contributed.
    */
   List<TaskDescriptor> get taskDescriptors => taskExtensionPoint.extensions;
 
   @override
   String get uniqueIdentifier => UNIQUE_IDENTIFIER;
 
@@ skipping 25 matching lines @@
   @override
   void registerExtensions(RegisterExtension registerExtension) {
     _registerTaskExtensions(registerExtension);
     _registerWorkManagerFactoryExtensions(registerExtension);
     _registerDartErrorsForSource(registerExtension);
     _registerDartErrorsForUnit(registerExtension);
     _registerHtmlErrors(registerExtension);
   }
 
   void _registerDartErrorsForSource(RegisterExtension registerExtension) {
-    String id = DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID;
-    registerExtension(id, PARSE_ERRORS);
-    registerExtension(id, SCAN_ERRORS);
+    registerExtension(DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID, PARSE_ERRORS);
+    registerExtension(DART_ERRORS_FOR_SOURCE_EXTENSION_POINT_ID, SCAN_ERRORS);
   }
 
   void _registerDartErrorsForUnit(RegisterExtension registerExtension) {
-    String id = DART_ERRORS_FOR_UNIT_EXTENSION_POINT_ID;
-    registerExtension(id, LIBRARY_UNIT_ERRORS);
+    registerExtension(
+        DART_ERRORS_FOR_UNIT_EXTENSION_POINT_ID, LIBRARY_UNIT_ERRORS);
   }
 
   void _registerHtmlErrors(RegisterExtension registerExtension) {
-    String id = HTML_ERRORS_EXTENSION_POINT_ID;
-    registerExtension(id, HTML_DOCUMENT_ERRORS);
+    registerExtension(HTML_ERRORS_EXTENSION_POINT_ID, HTML_DOCUMENT_ERRORS);
   }
 
   void _registerTaskExtensions(RegisterExtension registerExtension) {
     String taskId = TASK_EXTENSION_POINT_ID;
     //
     // Register general tasks.
     //
     registerExtension(taskId, GetContentTask.DESCRIPTOR);
     //
     // Register Dart tasks.
@@ skipping 79 matching lines @@
    * a [WorkManagerFactory].
    */
   void _validateWorkManagerFactoryExtension(Object extension) {
     if (extension is! WorkManagerFactory) {
       String id = taskExtensionPoint.uniqueIdentifier;
       throw new ExtensionError(
           'Extensions to $id must be a WorkManagerFactory');
     }
   }
 }
+
+/**
+ * Annotation describing the relationship between a getter in [EnginePlugin]
+ * and the associated identifier (in '../../plugin/task.dart') which can be
+ * passed to the extension manager to populate it.
+ *
+ * This annotation is not used at runtime; it is used to aid in static analysis
+ * of the task model during development.
+ */
+class ExtensionPointId {
+  final String extensionPointId;
+
+  const ExtensionPointId(this.extensionPointId);
+}