anchor.diff:      } else {
         messages.add(ValidationMessage(_userMessages.intellijLocation(installPath)));
   
  -      final IntelliJPlugins plugins = IntelliJPlugins(pluginsPath, fileSystem: _fileSystem);
  +      final IntelliJPlugins plugins = IntelliJPlugins(pluginsPath!, fileSystem: _fileSystem);
         plugins.validatePackage(
           messages,
           <String>['flutter-intellij', 'flutter-intellij.jar'],
  
positive.code:   final String pluginsPath;
  
    static Iterable<DoctorValidator> installed({
      @required FileSystem fileSystem,
      @required FileSystemUtils fileSystemUtils,
      @required UserMessages userMessages,
    }) {
      final List<DoctorValidator> validators = <DoctorValidator>[];
      if (fileSystemUtils.homeDirPath == null) {
        return validators;
      }
  
  
negative.code:     final String major = split[0];
      final String minor = split[1];
  
      final String? homeDirPath = _homeDirPath;
      if (homeDirPath != null) {
        String pluginsPath = _fileSystem.path.join(
          homeDirPath,
          'Library',
          'Application Support',
          'JetBrains',
          '$id$major.$minor',
          'plugins',
        );
        // Fallback to legacy location from < 2020.
        if (!_fileSystem.isDirectorySync(pluginsPath)) {
          pluginsPath = _fileSystem.path.join(
            homeDirPath,
            'Library',
            'Application Support',
            '$id$major.$minor',
          );
        }
        _pluginsPath = pluginsPath;
      }
  
      return _pluginsPath;
    }
    String? _pluginsPath;
  }
  