anchor.diff:  }
   
   /// Indicate that [callback] is expected to be called a [count] number of times
  -/// (by default 1). The unittest framework will wait for the callback to run the
  +/// (by default 1).
  +///
  +/// The unittest framework will wait for the callback to run the
   /// specified [count] times before it continues with the following test.  Using
   /// [expectAsync] will also ensure that errors that occur within [callback] are
   /// tracked and reported. [callback] should take 0 positional arguments (named
   /// arguments are not supported). [id] can be used to provide more
   /// descriptive error messages if the callback is called more often than
  -/// expected. [max] can be used to specify an upper bound on the number of
  +/// expected.
  +///
  +/// [max] can be used to specify an upper bound on the number of
   /// calls; if this is exceeded the test will fail (or be marked as in error if
   /// it was already complete). A value of 0 for [max] (the default) will set
   /// the upper bound to the same value as [count]; i.e. the callback should be
  
positive.code:   _currentContext.testSetup = setupTest;
  }
  
  /// Register a [tearDown] function for a test [group]. This function will
  /// be called after each test in the group is run. Note that if groups
  /// are nested only the most locally scoped [teardownTest] function will be run.
  /// [setUp] and [tearDown] should be called within the [group] before any
  /// calls to [test]. The [teardownTest] function can be asynchronous; in this
  /// case it must return a [Future].
  void tearDown(Function teardownTest) {
    _requireNotRunning();
    _currentContext.testTeardown = teardownTest;
  
negative.code: bool formatStacks = true;
  
  /// A flag that controls whether we try to filter out irrelevant frames from
  /// the stack trace.
  ///
  /// Requires [formatStacks] to be set.
  bool filterStacks = true;
  
  void _requireNotRunning() {
  