anchor.diff:        if (packages != null) {
           packageMap = _getPackageMap(packages);
         } else {
  -
           // Fall back to pub list-dir.
   
           PubPackageMapProvider pubPackageMapProvider =
  
positive.code:     for (var package in packages) {
        var packageName = path.basename(package.path);
        var realPath = package.resolveSymbolicLinksSync();
        result[packageName] =
            [PhysicalResourceProvider.INSTANCE.getFolder(realPath)];
      }
      return result;
    }
  
negative.code: typedef ErrorSeverity _BatchRunnerHandler(List<String> args);
  
  class Driver {
    /// The plugins that are defined outside the `analyzer_cli` package.
    List<Plugin> _userDefinedPlugins = <Plugin>[];
  
  