support part file completions

pkg/analysis_server/lib/src/services/completion/dart_completion_manager.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.completion.dart;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/arglist_computer.dart';
@@ skipping 61 matching lines @@
         context,
         searchEngine,
         source,
         new DartCompletionCache(context, source));
   }
 
   @override
   Future<bool> computeCache() {
     return waitForAnalysis().then((CompilationUnit unit) {
       if (unit != null && !cache.isImportInfoCached(unit)) {
-        return cache.computeImportInfo(unit, searchEngine);
+        return cache.computeImportInfo(unit, searchEngine, true);
       } else {
         return new Future.value(false);
       }
     });
   }
 
   /**
    * Compute suggestions based upon cached information only
    * then send an initial response to the client.
    * Return a list of computers for which [computeFull] should be called
@@ skipping 89 matching lines @@
       controller.close();
     }
   }
 
   /**
    * Return a future that either (a) completes with the resolved compilation
    * unit when analysis is complete, or (b) completes with null if the
    * compilation unit is never going to be resolved.
    */
   Future<CompilationUnit> waitForAnalysis() {
+    List<Source> libraries = context.getLibrariesContaining(source);
+    assert(libraries != null);
+    if (libraries.length == 0) {
+      return new Future.value(null);
+    }
+    Source libSource = libraries[0];
+    assert(libSource != null);
     return context.computeResolvedCompilationUnitAsync(
         source,
-        source).catchError((_) {
+        libSource).catchError((_) {
       // This source file is not scheduled for analysis, so a resolved
       // compilation unit is never going to get computed.
       return null;
     }, test: (e) => e is AnalysisNotScheduledError);
   }
 }
 
 /**
  * The context in which the completion is requested.
  */
@@ skipping 93 matching lines @@
   _ReplacementOffsetBuilder(this.request) {
     request.replacementOffset = request.offset;
     request.replacementLength = 0;
   }
 
   visitSimpleIdentifier(SimpleIdentifier node) {
     request.replacementOffset = node.offset;
     request.replacementLength = node.length;
   }
 }