Support for searching LabelElements in SearchEngine.

pkg/analysis_server/lib/src/services/search/search_engine_internal.dart

 // Copyright (c) 2014, 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 services.src.search.search_engine;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/services/index/index.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
@@ skipping 63 matching lines @@
         element.kind == ElementKind.TOP_LEVEL_VARIABLE) {
       return _searchReferences_Field(element as PropertyInducingElement);
     } else if (element.kind == ElementKind.FUNCTION) {
       return _searchReferences_Function(element as FunctionElement);
     } else if (element.kind == ElementKind.GETTER ||
         element.kind == ElementKind.SETTER) {
       return _searchReferences_PropertyAccessor(
           element as PropertyAccessorElement);
     } else if (element.kind == ElementKind.IMPORT) {
       return _searchReferences_Import(element as ImportElement);
+    } else if (element.kind == ElementKind.LABEL) {
+      return _searchReferences_Label(element as LabelElement);
     } else if (element.kind == ElementKind.LIBRARY) {
       return _searchReferences_Library(element as LibraryElement);
     } else if (element.kind == ElementKind.LOCAL_VARIABLE) {
       return _searchReferences_LocalVariable(element as LocalVariableElement);
     } else if (element.kind == ElementKind.METHOD) {
       return _searchReferences_Method(element as MethodElement);
     } else if (element.kind == ElementKind.PARAMETER) {
       return _searchReferences_Parameter(element as ParameterElement);
     } else if (element.kind == ElementKind.FUNCTION_TYPE_ALIAS) {
       return _searchReferences_FunctionTypeAlias(
@@ skipping 41 matching lines @@
   }
 
   Future<List<SearchMatch>> _searchReferences_Class(ClassElement clazz) {
     _Requestor requestor = new _Requestor(_index);
     requestor.add(clazz, IndexConstants.IS_REFERENCED_BY, MatchKind.REFERENCE);
     return requestor.merge();
   }
 
   Future<List<SearchMatch>>
       _searchReferences_CompilationUnit(CompilationUnitElement unit) {
-    // TODO(merge?)
     _Requestor requestor = new _Requestor(_index);
     requestor.add(unit, IndexConstants.IS_REFERENCED_BY, MatchKind.REFERENCE);
     return requestor.merge();
   }
 
   Future<List<SearchMatch>>
       _searchReferences_Constructor(ConstructorElement constructor) {
     _Requestor requestor = new _Requestor(_index);
     requestor.add(
         constructor,
@@ skipping 43 matching lines @@
     requestor.add(alias, IndexConstants.IS_REFERENCED_BY, MatchKind.REFERENCE);
     return requestor.merge();
   }
 
   Future<List<SearchMatch>> _searchReferences_Import(ImportElement imp) {
     _Requestor requestor = new _Requestor(_index);
     requestor.add(imp, IndexConstants.IS_REFERENCED_BY, MatchKind.REFERENCE);
     return requestor.merge();
   }
 
+  Future<List<SearchMatch>> _searchReferences_Label(LabelElement variable) {
+    _Requestor requestor = new _Requestor(_index);
+    requestor.add(
+        variable,
+        IndexConstants.IS_REFERENCED_BY,
+        MatchKind.REFERENCE);
+    return requestor.merge();
+  }
+
   Future<List<SearchMatch>> _searchReferences_Library(LibraryElement library) {
     _Requestor requestor = new _Requestor(_index);
     requestor.add(
         library,
         IndexConstants.IS_REFERENCED_BY,
         MatchKind.REFERENCE);
     return requestor.merge();
   }
 
   Future<List<SearchMatch>>
@@ skipping 84 matching lines @@
     });
     futures.add(matchesFuture);
   }
 
   Future<List<SearchMatch>> merge() {
     return Future.wait(futures).then((List<List<SearchMatch>> matchesList) {
       return matchesList.expand((matches) => matches).toList();
     });
   }
 }