anchor.diff:      for (String testOs in testPlatforms) {
         testUsingContext('AnsiSpinner works for $testOs (1)', () async {
           bool done = false;
  +        mockStopwatch = FakeStopwatch();
           FakeAsync().run((FakeAsync time) {
             final AnsiSpinner ansiSpinner = AnsiSpinner(
               timeout: const Duration(hours: 10),
  
positive.code: 
      void doWhileAsync(FakeAsync time, bool doThis()) {
        do {
          time.elapse(const Duration(milliseconds: 1));
        } while (doThis());
      }
  
negative.code:       }, overrides: <Type, Generator>{
          Platform: () => FakePlatform(operatingSystem: testOs),
          Stdio: () => mockStdio,
          Stopwatch: () => mockStopwatch,
        });
  
        testUsingContext('AnsiSpinner works for $testOs (2)', () async {
  