anchor.diff:    }
   
     Future<ProjectAnalyzer> _createProjectAnalyzer(Project project) {
  -    if (_contextMap[project] != null) {
  -      return new Future.value(_contextMap[project]);
  -    }
  -
       _logger.info('creating analysis context [${project.name}]');
       Stopwatch timer = new Stopwatch()..start();
   
       ProjectAnalyzer context = new ProjectAnalyzer._(this, project);
  -    _contextMap[project] = context;
       _recentContexts.insert(0, context);
   
       if (_recentContexts.length > MAX_CONTEXTS) {
  
positive.code:       _contextCompleters.containsKey(project);
  
    Future<ProjectAnalyzer> getCreateProjectAnalyzer(Project project) {
      ProjectAnalyzer context = _contextMap[project];
      Completer completer = _contextCompleters[project];
  
      if (completer == null) {
  
negative.code:   // our memory consumption.
    static final int MAX_CONTEXTS = 5;
  
    Map<Project, Completer> _contextCompleters = {};
  
    List<ProjectAnalyzer> _recentContexts = [];
  