Work in progress: front end hot reload API

pkg/analyzer/lib/src/summary/package_bundle_reader.dart

 import 'dart:io' as io;
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/context/context.dart';
 import 'package:analyzer/src/dart/element/element.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/idl.dart';
 import 'package:analyzer/src/summary/resynthesize.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/src/util/fast_uri.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/general.dart';
 import 'package:analyzer/task/model.dart';
-import 'package:path/path.dart' as pathos;
+import 'package:front_end/src/base/source.dart';
 
 /**
  * The [ResultProvider] that provides results from input package summaries.
  */
 class InputPackagesResultProvider extends ResynthesizerResultProvider {
   InputPackagesResultProvider(
       InternalAnalysisContext context, SummaryDataStore dataStore)
       : super(context, dataStore) {
     AnalysisContext sdkContext = context.sourceFactory.dartSdk.context;
     createResynthesizer(sdkContext, sdkContext.typeProvider);
@@ skipping 27 matching lines @@
     }
     return null;
   }
 }
 
 /**
  * A placeholder of a source that is part of a package whose analysis results
  * are served from its summary.  This source uses its URI as [fullName] and has
  * empty contents.
  */
-class InSummarySource extends Source {
-  final Uri uri;
-
+class InSummarySource extends BasicSource {
   /**
    * The summary file where this source was defined.
    */
   final String summaryPath;
 
-  InSummarySource(this.uri, this.summaryPath);
+  InSummarySource(Uri uri, this.summaryPath) : super(uri);
 
   @override
   TimestampedData<String> get contents => new TimestampedData<String>(0, '');
 
   @override
-  String get encoding => uri.toString();
-
-  @override
-  String get fullName => encoding;
-
-  @override
-  int get hashCode => uri.hashCode;
-
-  @override
-  bool get isInSystemLibrary => uri.scheme == DartUriResolver.DART_SCHEME;
-
-  @override
   int get modificationStamp => 0;
 
   @override
-  String get shortName => pathos.basename(fullName);
-
-  @override
   UriKind get uriKind => UriKind.PACKAGE_URI;
 
   @override
-  bool operator ==(Object object) => object is Source && object.uri == uri;
-
-  @override
   bool exists() => true;
 
   @override
   String toString() => uri.toString();
 }
 
 /**
  * The [UriResolver] that knows about sources that are served from their
  * summaries.
  */
@@ skipping 349 matching lines @@
   UnlinkedUnit getUnlinkedSummary(String uri) {
     return _dataStore.unlinkedMap[uri];
   }
 
   @override
   bool hasLibrarySummary(String uri) {
     LinkedLibrary linkedLibrary = _dataStore.linkedMap[uri];
     return linkedLibrary != null;
   }
 }