anchor.diff:            help: 'Enable support for the proposed async feature.',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('enable-enum',
             help: 'Enable support for the proposed enum feature.',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('enable-conditional-directives',
             help:
                 'deprecated -- Enable support for conditional directives (DEP 40).',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('enable-null-aware-operators',
             help: 'Enable support for null-aware operators (DEP 9).',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('enable-strict-call-checks',
             help: 'Fix issue 21938.',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('enable-new-task-model',
             help: 'deprecated -- Ennable new task model.',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('initializing-formal-access',
             help:
                 'Enable support for allowing access to field formal parameters in a constructor\'s initializer list',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('supermixin',
             help: 'Relax restrictions on mixins (DEP 34).',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('log',
             help: 'Log additional messages and exceptions.',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('enable_type_checks',
             help: 'Check types in constant evaluation.',
             defaultsTo: false,
             negatable: false,
  -          hide: true)
  +          hide: hide)
         ..addFlag('strong',
             help: 'Enable strong static checks (https://goo.gl/DqcBsw)')
         ..addFlag('no-implicit-casts',
  
positive.code:       args = argsFile.readAsLinesSync();
      }
  
      args = args.expand((String arg) => arg.split('=')).toList();
      var parser = new CommandLineParser()
        ..addFlag('batch',
  
negative.code:           help: 'Enable Bazel persistent worker mode.',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        ..addOption('build-analysis-output',
            help:
                'Specifies the path to the file where analysis results should be written.',
            hide: hide)
        ..addFlag('build-mode',
            // TODO(paulberry): add more documentation.
            help: 'Enable build mode.',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        ..addOption('build-summary-input',
            help: 'Path to a summary file that contains information from a '
                'previous analysis run.  May be specified multiple times.',
            allowMultiple: true,
            hide: hide)
        ..addOption('build-summary-output',
            help: 'Specifies the path to the file where the full summary '
                'information should be written.',
            hide: hide)
        ..addOption('build-summary-output-semantic',
            help: 'Specifies the path to the file where the semantic summary '
                'information should be written.',
            hide: hide)
        ..addFlag('build-summary-only',
            help: 'Disable analysis (only generate summaries).',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        ..addFlag('build-summary-only-ast',
            help: 'deprecated -- Generate summaries using ASTs.',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        ..addFlag('build-summary-only-diet',
            help: 'Diet parse function bodies.',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        ..addFlag('build-summary-exclude-informative',
            help: 'Exclude @informative information (docs, offsets, etc).  '
                'Deprecated: please use --build-summary-output-semantic instead.',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        ..addFlag('build-suppress-exit-code',
            help: 'Exit with code 0 even if errors are found.',
            defaultsTo: false,
            negatable: false,
            hide: hide)
        //
        // Hidden flags.
        //
  