anchor.diff:    /// Attempts a fling gesture starting from the given location, moving the
     /// given distance, reaching the given speed.
     ///
  -  /// Exactly 50 pointer events are synthesized.
  -  ///
  -  /// The offset and speed control the interval between each pointer event. For
  -  /// example, if the offset is 200 pixels down, and the speed is 800 pixels per
  -  /// second, the pointer events will be sent for each increment of 4 pixels
  -  /// (200/50), over 250ms (200/800), meaning events will be sent every 1.25ms
  -  /// (250/200).
  -  ///
  -  /// To make tests more realistic, frames may be pumped during this time (using
  -  /// calls to [pump]). If the total duration is longer than `frameInterval`,
  -  /// then one frame is pumped each time that amount of time elapses while
  -  /// sending events, or each time an event is synthesized, whichever is rarer.
  +  /// {@macro flutter.flutter_test.fling}
     ///
     /// A fling is essentially a drag that ends at a particular speed. If you
     /// just want to drag and end without a fling, use [dragFrom].
  -  ///
  -  /// The `initialOffset` argument, if non-zero, causes the pointer to first
  -  /// apply that offset, then pump a delay of `initialOffsetDelay`. This can be
  -  /// used to simulate a drag followed by a fling, including dragging in the
  -  /// opposite direction of the fling (e.g. dragging 200 pixels to the right,
  -  /// then fling to the left over 200 pixels, ending at the exact point that the
  -  /// drag started).
     Future<void> flingFrom(
       Offset startLocation,
       Offset offset,
  
positive.code:   /// If the middle of the widget is not exposed, this might send
    /// events to another object.
    ///
    /// This can pump frames. See [flingFrom] for a discussion of how the
    /// `offset`, `velocity` and `frameInterval` arguments affect this.
    ///
    /// The `speed` is in pixels per second in the direction given by `offset`.
    ///
    /// A fling is essentially a drag that ends at a particular speed. If you
    /// just want to drag and end without a fling, use [drag].
    ///
    /// The `initialOffset` argument, if non-zero, causes the pointer to first
    /// apply that offset, then pump a delay of `initialOffsetDelay`. This can be
  
negative.code:   /// opposite direction of the fling (e.g. dragging 200 pixels to the right,
    /// then fling to the left over 200 pixels, ending at the exact point that the
    /// drag started).
    /// {@endtemplate}
    ///
    /// A fling is essentially a drag that ends at a particular speed. If you
    /// just want to drag and end without a fling, use [drag].
    Future<void> fling(
      Finder finder,
      Offset offset,
  