anchor.diff:  // Use of this source code is governed by a BSD-style license that can be
   // found in the LICENSE file.
   
  -// @dart = 2.8
  -
   import 'dart:math' as math;
  -
  -import 'package:meta/meta.dart';
   
   import 'logger.dart';
   import 'platform.dart';
  
positive.code:     this.key,
      this.description, {
      this.inParenthesis = '',
      @required Logger logger,
      @required Terminal terminal,
      @required Platform platform,
      @required OutputPreferences outputPreferences,
    }) : _logger = logger,
         _terminal = terminal,
         _platform = platform,
  
negative.code: 
    final OutputPreferences _outputPreferences;
  
    late final CommandHelpOption I = _makeOption(
      'I',
      'Toggle oversized image inversion $image.',
      'debugInvertOversizedImages',
    );
  
    late final CommandHelpOption L = _makeOption(
      'L',
      'Dump layer tree to the console.',
      'debugDumpLayerTree',
    );
  
    late final CommandHelpOption P = _makeOption(
      'P',
      'Toggle performance overlay.',
      'WidgetsApp.showPerformanceOverlay',
    );
  
    late final CommandHelpOption R = _makeOption(
      'R',
      'Hot restart.',
    );
  
    late final CommandHelpOption S = _makeOption(
      'S',
      'Dump accessibility tree in traversal order.',
      'debugDumpSemantics',
    );
  
    late final CommandHelpOption U = _makeOption(
      'U',
      'Dump accessibility tree in inverse hit test order.',
      'debugDumpSemantics',
    );
  
    late final CommandHelpOption a = _makeOption(
      'a',
      'Toggle timeline events for all widget build methods.',
      'debugProfileWidgetBuilds',
    );
  
    late final CommandHelpOption b = _makeOption(
      'b',
      'Toggle the platform brightness setting (dark and light mode).',
      'debugBrightnessOverride',
    );
  
    late final CommandHelpOption c = _makeOption(
      'c',
      'Clear the screen',
    );
  
    late final CommandHelpOption d = _makeOption(
      'd',
      'Detach (terminate "flutter run" but leave application running).',
    );
  
    late final CommandHelpOption g = _makeOption(
      'g',
      'Run source code generators.'
    );
  
    late final CommandHelpOption h = _makeOption(
      'h',
      'Repeat this help message.',
    );
  
    late final CommandHelpOption i = _makeOption(
      'i',
      'Toggle widget inspector.',
      'WidgetsApp.showWidgetInspectorOverride',
    );
  
    late final CommandHelpOption o = _makeOption(
      'o',
      'Simulate different operating systems.',
      'defaultTargetPlatform',
    );
  
    late final CommandHelpOption p = _makeOption(
      'p',
      'Toggle the display of construction lines.',
      'debugPaintSizeEnabled',
    );
  
    late final CommandHelpOption q = _makeOption(
      'q',
      'Quit (terminate the application on the device).',
    );
  
    late final CommandHelpOption r = _makeOption(
      'r',
      'Hot reload. $fire$fire$fire',
    );
  
    late final CommandHelpOption s = _makeOption(
      's',
      'Save a screenshot to flutter.png.',
    );
  
    late final CommandHelpOption t = _makeOption(
      't',
      'Dump rendering tree to the console.',
      'debugDumpRenderTree',
    );
  
    late final CommandHelpOption v = _makeOption(
      'v',
      'Launch DevTools.',
    );
  
    late final CommandHelpOption w = _makeOption(
      'w',
      'Dump widget hierarchy to the console.',
      'debugDumpApp',
    );
  
    late final CommandHelpOption z = _makeOption(
      'z',
      'Toggle elevation checker.',
    );
  
    late final CommandHelpOption k = _makeOption(
      'k',
      'Toggle CanvasKit rendering.',
    );
  
    late final CommandHelpOption M = _makeOption(
      'M',
      'Write SkSL shaders to a unique file in the project directory.',
    );
  