anchor.diff:    /// Internal implementation of the completion mechanism.
     Future<Map> _completeImpl(Map<String, String> sources,
                               String sourceName, int offset) async {
  -    sources = _rewriteOverlayNamesToPaths(sources);
  +    sources = _getOverlayMapWithPaths(sources);
       String path = _getPathFromName(sourceName);
       await serverConnection._ensureSetup();
       await serverConnection.loadSources(sources);
  
positive.code: 
    Future<EditGetFixesResult> _getFixesImpl(
        Map<String, String> sources, String sourceName, int offset) async {
      sources = _rewriteOverlayNamesToPaths(sources);
      String path = _getPathFromName(sourceName);
  
      await serverConnection._ensureSetup();
  
negative.code:     return formatResult;
    }
  
    Map<String, String> _getOverlayMapWithPaths(Map<String, String> overlay) {
      var newOverlay = {};
      overlay.forEach((k,v) => newOverlay.putIfAbsent(
        _getPathFromName(k), () => v)
  