anchor.diff:      final collection = AnalysisContextCollection(
         includedPaths: root.includedPaths.toList(),
         excludedPaths: root.excludedPaths.toList(),
  -      resourceProvider: PhysicalResourceProvider.INSTANCE,
  +      resourceProvider: _provider,
       );
  +
       var context = collection.contexts[0];
   //    // Set the DeclarationsTracker, only call doWork to build up the available
   //    // suggestions if doComputeCompletionsFromAnalysisServer is true.
  
positive.code:             // First we compute the completions useNewRelevance set to
              // false:
              var suggestions = await _computeCompletionSuggestions(
                  _resolvedUnitResult,
                  expectedCompletion.offset,
                  metricsOldMode,
                  false);
  
negative.code:     help: 'Print additional information about the analysis',
      negatable: false,
    );
    parser.addOption('overlay',
        allowed: [
          OVERLAY_NONE,
          OVERLAY_REMOVE_TOKEN,
          OVERLAY_REMOVE_REST_OF_FILE
        ],
        defaultsTo: OVERLAY_NONE,
        help: 'Before attempting a completion at the location of each token, the '
            'token can be removed, or the rest of the file can be removed to test '
            'code completion with diverse methods. The default mode is to '
            'complete at the start of the token without modifying the file.');
    return parser;
  }
  
  