Issue 26639. Set source for mock 'dart:async' library.

pkg/analyzer/lib/src/context/context.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.context.context;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart';
@@ skipping 469 matching lines @@
     assert(!driver.isTaskRunning);
 
     Source coreSource = sourceFactory.forUri(DartSdk.DART_CORE);
     if (coreSource == null) {
       throw new AnalysisException("Could not create a source for dart:core");
     }
     LibraryElement coreElement = computeLibraryElement(coreSource);
     if (coreElement == null) {
       throw new AnalysisException("Could not create an element for dart:core");
     }
+
     LibraryElement asyncElement;
     if (analysisOptions.enableAsync) {
       Source asyncSource = sourceFactory.forUri(DartSdk.DART_ASYNC);
       if (asyncSource == null) {
         throw new AnalysisException("Could not create a source for dart:async");
       }
       asyncElement = computeLibraryElement(asyncSource);
       if (asyncElement == null) {
         throw new AnalysisException(
             "Could not create an element for dart:async");
       }
     } else {
-      asyncElement = createMockAsyncLib(coreElement);
+      Source asyncSource = sourceFactory.forUri(DartSdk.DART_ASYNC);
+      asyncElement = createMockAsyncLib(coreElement, asyncSource);
     }
+
     _typeProvider = new TypeProviderImpl(coreElement, asyncElement);
     return _typeProvider;
   }
 
   /**
    * Sets the [TypeProvider] for this context.
    */
   @override
   void set typeProvider(TypeProvider typeProvider) {
     _typeProvider = typeProvider;
@@ skipping 204 matching lines @@
       }
     });
     return cache;
   }
 
   /**
    * Create a minimalistic mock dart:async library
    * to stand in for a real one if one does not exist
    * facilitating creation a type provider without dart:async.
    */
-  LibraryElement createMockAsyncLib(LibraryElement coreLibrary) {
+  LibraryElement createMockAsyncLib(LibraryElement coreLibrary, Source asyncSource) {
     InterfaceType objType = coreLibrary.getType('Object').type;
 
     ClassElement _classElement(String typeName, [List<String> parameterNames]) {
       ClassElementImpl element =
           new ClassElementImpl.forNode(AstFactory.identifier3(typeName));
       element.supertype = objType;
       if (parameterNames != null) {
         int count = parameterNames.length;
         if (count > 0) {
           List<TypeParameterElementImpl> typeParameters =
@@ skipping 14 matching lines @@
       return element;
     }
 
     InterfaceType futureType = _classElement('Future', ['T']).type;
     InterfaceType streamType = _classElement('Stream', ['T']).type;
     CompilationUnitElementImpl asyncUnit =
         new CompilationUnitElementImpl("mock_async.dart");
     asyncUnit.types = <ClassElement>[futureType.element, streamType.element];
     LibraryElementImpl mockLib = new LibraryElementImpl.forNode(
         this, AstFactory.libraryIdentifier2(["dart.async"]));
+    asyncUnit.librarySource = asyncSource;
+    asyncUnit.source = asyncSource;
     mockLib.definingCompilationUnit = asyncUnit;
     mockLib.publicNamespace =
         new NamespaceBuilder().createPublicNamespaceForLibrary(mockLib);
     return mockLib;
   }
 
   @override
   void dispose() {
     _disposed = true;
     for (List<PendingFuture> pendingFutures in _pendingFutureTargets.values) {
@@ skipping 1443 matching lines @@
     }
     DartSdk sdk = factory.dartSdk;
     if (sdk == null) {
       throw new IllegalArgumentException(
           "The source factory for an SDK analysis context must have a DartUriResolver");
     }
     return new AnalysisCache(
         <CachePartition>[AnalysisEngine.instance.partitionManager.forSdk(sdk)]);
   }
 }