Treat hover events as normal pointer events, and bring them back to Listener (#63834)

packages/flutter/lib/src/gestures/binding.dart

@@ -270,7 +270,7 @@ mixin GestureBinding on BindingBase implements HitTestable, HitTestDispatcher, H
   void handlePointerEvent(PointerEvent event) {
     assert(!locked);
     HitTestResult? hitTestResult;
-    if (event is PointerDownEvent || event is PointerSignalEvent) {
+    if (event is PointerDownEvent || event is PointerSignalEvent || event is PointerHoverEvent) {
       assert(!_hitTests.containsKey(event.pointer));
       hitTestResult = HitTestResult();
       hitTest(hitTestResult, event.position);
@@ -298,7 +298,6 @@ mixin GestureBinding on BindingBase implements HitTestable, HitTestDispatcher, H
       return true;
     }());
     if (hitTestResult != null ||
-        event is PointerHoverEvent ||
         event is PointerAddedEvent ||
         event is PointerRemovedEvent) {
       assert(event.position != null);
@@ -318,8 +317,8 @@ mixin GestureBinding on BindingBase implements HitTestable, HitTestDispatcher, H
   /// null, the event is also sent to every [HitTestTarget] in the entries of the
   /// given [HitTestResult]. Any exceptions from the handlers are caught.
   ///
-  /// The `hitTestResult` argument may only be null for [PointerHoverEvent]s,
-  /// [PointerAddedEvent]s, or [PointerRemovedEvent]s.
+  /// The `hitTestResult` argument may only be null for [PointerAddedEvent]s or
+  /// [PointerRemovedEvent]s.
   @override // from HitTestDispatcher
   void dispatchEvent(PointerEvent event, HitTestResult? hitTestResult) {
     assert(!locked);
@@ -327,7 +326,7 @@ mixin GestureBinding on BindingBase implements HitTestable, HitTestDispatcher, H
     // [PointerAddedEvent], or [PointerRemovedEvent]. These events are specially
     // routed here; other events will be routed through the `handleEvent` below.
     if (hitTestResult == null) {
-      assert(event is PointerHoverEvent || event is PointerAddedEvent || event is PointerRemovedEvent);
+      assert(event is PointerAddedEvent || event is PointerRemovedEvent);
       try {
         pointerRouter.route(event);
       } catch (exception, stack) {

packages/flutter/lib/src/rendering/binding.dart

@@ -259,7 +259,6 @@ mixin RendererBinding on BindingBase, ServicesBinding, SchedulerBinding, Gesture
   @override // from GestureBinding
   void dispatchEvent(PointerEvent event, HitTestResult? hitTestResult) {
     if (hitTestResult != null ||
-        event is PointerHoverEvent ||
         event is PointerAddedEvent ||
         event is PointerRemovedEvent) {
       assert(event.position != null);

packages/flutter/lib/src/rendering/mouse_tracking.dart

@@ -53,7 +53,6 @@ class MouseTrackerAnnotation with Diagnosticable {
   /// All arguments are optional. The [cursor] must not be null.
   const MouseTrackerAnnotation({
     this.onEnter,
-    this.onHover,
     this.onExit,
     this.cursor = MouseCursor.defer,
   }) : assert(cursor != null);
@@ -72,16 +71,6 @@ class MouseTrackerAnnotation with Diagnosticable {
   ///  * [MouseRegion.onEnter], which uses this callback.
   final PointerEnterEventListener? onEnter;
 
-  /// Triggered when a mouse pointer has moved onto or within the region without
-  /// buttons pressed.
-  ///
-  /// This callback is not triggered by the movement of an annotation.
-  ///
-  /// See also:
-  ///
-  ///  * [MouseRegion.onHover], which uses this callback.
-  final PointerHoverEventListener? onHover;
-
   /// Triggered when a mouse pointer, with or without buttons pressed, has
   /// exited the region.
   ///
@@ -482,8 +471,6 @@ abstract class BaseMouseTracker extends ChangeNotifier {
 mixin _MouseTrackerEventMixin on BaseMouseTracker {
   // Handles device update and dispatches mouse event callbacks.
   static void _handleDeviceUpdateMouseEvents(MouseTrackerUpdateDetails details) {
-    final PointerEvent? previousEvent = details.previousEvent;
-    final PointerEvent? triggeringEvent = details.triggeringEvent;
     final PointerEvent latestEvent = details.latestEvent;
 
     final LinkedHashMap<MouseTrackerAnnotation, Matrix4> lastAnnotations = details.lastAnnotations;
@@ -514,24 +501,6 @@ mixin _MouseTrackerEventMixin on BaseMouseTracker {
       if (annotation.onEnter != null)
         annotation.onEnter!(baseEnterEvent.transformed(nextAnnotations[annotation]));
     }
-
-    // Send hover events to annotations that are in next, in reverse visual
-    // order. The reverse visual order is chosen only because of the simplicity
-    // by keeping the hover events aligned with enter events.
-    if (triggeringEvent is PointerHoverEvent) {
-      final Offset? hoverPositionBeforeUpdate = previousEvent is PointerHoverEvent ? previousEvent.position : null;
-      final bool pointerHasMoved = hoverPositionBeforeUpdate == null || hoverPositionBeforeUpdate != triggeringEvent.position;
-      // If the hover event follows a non-hover event, or has moved since the
-      // last hover, then trigger the hover callback on all annotations.
-      // Otherwise, trigger the hover callback only on annotations that it
-      // newly enters.
-      final Iterable<MouseTrackerAnnotation> hoveringAnnotations = pointerHasMoved ? nextAnnotations.keys.toList().reversed : enteringAnnotations;
-      for (final MouseTrackerAnnotation annotation in hoveringAnnotations) {
-        if (annotation.onHover != null) {
-          annotation.onHover!(triggeringEvent.transformed(nextAnnotations[annotation]));
-        }
-      }
-    }
   }
 
   @protected

packages/flutter/lib/src/rendering/platform_view.dart

@@ -723,13 +723,6 @@ mixin _PlatformViewGestureMixin on RenderBox implements MouseTrackerAnnotation {
   @override
   PointerEnterEventListener? get onEnter => null;
 
-  @override
-  PointerHoverEventListener get onHover => _handleHover;
-  void _handleHover(PointerHoverEvent event) {
-    if (_handlePointerEvent != null)
-      _handlePointerEvent!(event);
-  }
-
   @override
   PointerExitEventListener? get onExit => null;
 
@@ -741,6 +734,9 @@ mixin _PlatformViewGestureMixin on RenderBox implements MouseTrackerAnnotation {
     if (event is PointerDownEvent) {
       _gestureRecognizer!.addPointer(event);
     }
+    if (event is PointerHoverEvent) {
+      _handlePointerEvent?.call(event);
+    }
   }
 
   @override

packages/flutter/lib/src/rendering/proxy_box.dart

@@ -2662,10 +2662,10 @@ typedef PointerSignalEventListener = void Function(PointerSignalEvent event);
 /// Calls callbacks in response to common pointer events.
 ///
 /// It responds to events that can construct gestures, such as when the
-/// pointer is pressed, moved, then released or canceled.
+/// pointer is pointer is pressed and moved, and then released or canceled.
 ///
 /// It does not respond to events that are exclusive to mouse, such as when the
-/// mouse enters, exits or hovers a region without pressing any buttons. For
+/// mouse enters and exits a region without pressing any buttons. For
 /// these events, use [RenderMouseRegion].
 ///
 /// If it has a child, defers to the child for sizing behavior.
@@ -2679,6 +2679,7 @@ class RenderPointerListener extends RenderProxyBoxWithHitTestBehavior {
     this.onPointerDown,
     this.onPointerMove,
     this.onPointerUp,
+    this.onPointerHover,
     this.onPointerCancel,
     this.onPointerSignal,
     HitTestBehavior behavior = HitTestBehavior.deferToChild,
@@ -2697,6 +2698,9 @@ class RenderPointerListener extends RenderProxyBoxWithHitTestBehavior {
   /// contact with the screen.
   PointerUpEventListener? onPointerUp;
 
+  /// Called when a pointer that has not an [onPointerDown] changes position.
+  PointerHoverEventListener? onPointerHover;
+
   /// Called when the input from a pointer that triggered an [onPointerDown] is
   /// no longer directed towards this receiver.
   PointerCancelEventListener? onPointerCancel;
@@ -2712,16 +2716,18 @@ class RenderPointerListener extends RenderProxyBoxWithHitTestBehavior {
   @override
   void handleEvent(PointerEvent event, HitTestEntry entry) {
     assert(debugHandleEvent(event, entry));
-    if (onPointerDown != null && event is PointerDownEvent)
-      return onPointerDown!(event);
-    if (onPointerMove != null && event is PointerMoveEvent)
-      return onPointerMove!(event);
-    if (onPointerUp != null && event is PointerUpEvent)
-      return onPointerUp!(event);
-    if (onPointerCancel != null && event is PointerCancelEvent)
-      return onPointerCancel!(event);
-    if (onPointerSignal != null && event is PointerSignalEvent)
-      return onPointerSignal!(event);
+    if (event is PointerDownEvent)
+      return onPointerDown?.call(event);
+    if (event is PointerMoveEvent)
+      return onPointerMove?.call(event);
+    if (event is PointerUpEvent)
+      return onPointerUp?.call(event);
+    if (event is PointerHoverEvent)
+      return onPointerHover?.call(event);
+    if (event is PointerCancelEvent)
+      return onPointerCancel?.call(event);
+    if (event is PointerSignalEvent)
+      return onPointerSignal?.call(event);
   }
 
   @override
@@ -2733,6 +2739,7 @@ class RenderPointerListener extends RenderProxyBoxWithHitTestBehavior {
         'down': onPointerDown,
         'move': onPointerMove,
         'up': onPointerUp,
+        'hover': onPointerHover,
         'cancel': onPointerCancel,
         'signal': onPointerSignal,
       },
@@ -2821,7 +2828,10 @@ class RenderMouseRegion extends RenderProxyBox implements MouseTrackerAnnotation
   @override
   PointerEnterEventListener? onEnter;
 
-  @override
+  /// Triggered when a pointer has moved onto or within the region without
+  /// buttons pressed.
+  ///
+  /// This callback is not triggered by the movement of the object.
   PointerHoverEventListener? onHover;
 
   @override

packages/flutter/lib/src/services/platform_views.dart

@@ -848,6 +848,10 @@ abstract class AndroidViewController extends PlatformViewController {
   /// for description of the parameters.
   @override
   Future<void> dispatchPointerEvent(PointerEvent event) async {
+    if (event is PointerHoverEvent) {
+      return;
+    }
+
     if (event is PointerDownEvent) {
       _motionEventConverter.handlePointerDownEvent(event);
     }

packages/flutter/lib/src/widgets/basic.dart

@@ -5812,27 +5812,8 @@ class Listener extends StatelessWidget {
     Key? key,
     this.onPointerDown,
     this.onPointerMove,
-    // We have to ignore the lint rule here in order to use deprecated
-    // parameters and keep backward compatibility.
-    // TODO(tongmu): After it goes stable, remove these 3 parameters from Listener
-    // and Listener should no longer need an intermediate class _PointerListener.
-    // https://github.com/flutter/flutter/issues/36085
-    @Deprecated(
-      'Use MouseRegion.onEnter instead. See MouseRegion.opaque for behavioral difference. '
-      'This feature was deprecated after v1.10.14.'
-    )
-    this.onPointerEnter,
-    @Deprecated(
-      'Use MouseRegion.onExit instead. See MouseRegion.opaque for behavioral difference. '
-      'This feature was deprecated after v1.10.14.'
-    )
-    this.onPointerExit,
-    @Deprecated(
-      'Use MouseRegion.onHover instead. See MouseRegion.opaque for behavioral difference. '
-      'This feature was deprecated after v1.10.14.'
-    )
-    this.onPointerHover,
     this.onPointerUp,
+    this.onPointerHover,
     this.onPointerCancel,
     this.onPointerSignal,
     this.behavior = HitTestBehavior.deferToChild,
@@ -5849,15 +5830,9 @@ class Listener extends StatelessWidget {
   /// Called when a pointer that triggered an [onPointerDown] changes position.
   final PointerMoveEventListener? onPointerMove;
 
-  /// Called when a pointer enters the region for this widget.
-  ///
-  /// This is only fired for pointers which report their location when not down
-  /// (e.g. mouse pointers, but not most touch pointers).
-  ///
-  /// If this is a mouse pointer, this will fire when the mouse pointer enters
-  /// the region defined by this widget, or when the widget appears under the
-  /// pointer.
-  final PointerEnterEventListener? onPointerEnter;
+  /// Called when a pointer that triggered an [onPointerDown] is no longer in
+  /// contact with the screen.
+  final PointerUpEventListener? onPointerUp;
 
   /// Called when a pointer that has not triggered an [onPointerDown] changes
   /// position.
@@ -5866,20 +5841,6 @@ class Listener extends StatelessWidget {
   /// (e.g. mouse pointers, but not most touch pointers).
   final PointerHoverEventListener? onPointerHover;
 
-  /// Called when a pointer leaves the region for this widget.
-  ///
-  /// This is only fired for pointers which report their location when not down
-  /// (e.g. mouse pointers, but not most touch pointers).
-  ///
-  /// If this is a mouse pointer, this will fire when the mouse pointer leaves
-  /// the region defined by this widget, or when the widget disappears from
-  /// under the pointer.
-  final PointerExitEventListener? onPointerExit;
-
-  /// Called when a pointer that triggered an [onPointerDown] is no longer in
-  /// contact with the screen.
-  final PointerUpEventListener? onPointerUp;
-
   /// Called when the input from a pointer that triggered an [onPointerDown] is
   /// no longer directed towards this receiver.
   final PointerCancelEventListener? onPointerCancel;
@@ -5904,28 +5865,18 @@ class Listener extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    Widget? result = _child;
-    if (onPointerEnter != null ||
-        onPointerExit != null ||
-        onPointerHover != null) {
-      result = MouseRegion(
-        onEnter: onPointerEnter,
-        onExit: onPointerExit,
-        onHover: onPointerHover,
-        opaque: false,
-        child: result,
-      );
-    }
-    result = _PointerListener(
+    // TODO(dkwingsmt): Remove the extra wrapper, and make `Listener` a
+    // StatelessWidget. https://github.com/flutter/flutter/issues/65586
+    return _PointerListener(
       onPointerDown: onPointerDown,
       onPointerUp: onPointerUp,
       onPointerMove: onPointerMove,
+      onPointerHover: onPointerHover,
       onPointerCancel: onPointerCancel,
       onPointerSignal: onPointerSignal,
       behavior: behavior,
-      child: result,
+      child: _child,
     );
-    return result;
   }
 }
 
@@ -5935,6 +5886,7 @@ class _PointerListener extends SingleChildRenderObjectWidget {
     this.onPointerDown,
     this.onPointerMove,
     this.onPointerUp,
+    this.onPointerHover,
     this.onPointerCancel,
     this.onPointerSignal,
     this.behavior = HitTestBehavior.deferToChild,
@@ -5945,6 +5897,7 @@ class _PointerListener extends SingleChildRenderObjectWidget {
   final PointerDownEventListener? onPointerDown;
   final PointerMoveEventListener? onPointerMove;
   final PointerUpEventListener? onPointerUp;
+  final PointerHoverEventListener? onPointerHover;
   final PointerCancelEventListener? onPointerCancel;
   final PointerSignalEventListener? onPointerSignal;
   final HitTestBehavior behavior;
@@ -5955,6 +5908,7 @@ class _PointerListener extends SingleChildRenderObjectWidget {
       onPointerDown: onPointerDown,
       onPointerMove: onPointerMove,
       onPointerUp: onPointerUp,
+      onPointerHover: onPointerHover,
       onPointerCancel: onPointerCancel,
       onPointerSignal: onPointerSignal,
       behavior: behavior,
@@ -5967,6 +5921,7 @@ class _PointerListener extends SingleChildRenderObjectWidget {
       ..onPointerDown = onPointerDown
       ..onPointerMove = onPointerMove
       ..onPointerUp = onPointerUp
+      ..onPointerHover = onPointerHover
       ..onPointerCancel = onPointerCancel
       ..onPointerSignal = onPointerSignal
       ..behavior = behavior;
@@ -5987,11 +5942,15 @@ class _PointerListener extends SingleChildRenderObjectWidget {
   }
 }
 
-/// A widget that tracks the movement of mice, even when no button is pressed.
+/// A widget that tracks the movement of mice.
 ///
-/// It does not listen to events that can construct gestures, such as when the
-/// pointer is pressed, moved, then released or canceled. For these events,
-/// use [Listener], or more preferably, [GestureDetector].
+/// [MouseRegion] is used
+/// when it is needed to compare the list of objects that a mouse pointer is
+/// hovering over betweeen this frame and the last frame. This means entering
+/// events, exiting events, and mouse cursors.
+///
+/// To listen to general pointer events, use [Listener], or more preferably,
+/// [GestureDetector].
 ///
 /// ## Layout behavior
 ///
@@ -6110,13 +6069,23 @@ class MouseRegion extends StatefulWidget {
   ///    internally implemented.
   final PointerEnterEventListener? onEnter;
 
-  /// Triggered when a mouse pointer has moved onto or within the widget without
+  /// Triggered when a pointer moves into a position within this widget without
   /// buttons pressed.
   ///
-  /// This callback is not triggered by the movement of an annotation.
+  /// Usually this is only fired for pointers which report their location when
+  /// not down (e.g. mouse pointers). Certain devices also fire this event on
+  /// single taps in accessibility mode.
+  ///
+  /// This callback is not triggered by the movement of the widget.
   ///
   /// The time that this callback is triggered is during the callback of a
   /// pointer event, which is always between frames.
+  ///
+  /// See also:
+  ///
+  ///  * [Listener.onPointerHover], which does the same job. Prefer using
+  ///    [Listener.onPointerHover], since hover events are similar to other regular
+  ///    events.
   final PointerHoverEventListener? onHover;
 
   /// Triggered when a mouse pointer has exited this widget when the widget is

packages/flutter/test/gestures/gesture_binding_test.dart

@@ -105,7 +105,10 @@ void main() {
     _binding.callback = events.add;
 
     ui.window.onPointerDataPacket(packet);
-    expect(events.length, 0);
+    expect(events.length, 3);
+    expect(events[0], isA<PointerHoverEvent>());
+    expect(events[1], isA<PointerHoverEvent>());
+    expect(events[2], isA<PointerHoverEvent>());
     expect(pointerRouterEvents.length, 6,
         reason: 'pointerRouterEvents contains: $pointerRouterEvents');
     expect(pointerRouterEvents[0], isA<PointerAddedEvent>());

packages/flutter/test/rendering/mouse_tracking_test.dart

@@ -546,7 +546,7 @@ void main() {
     ui.window.onPointerDataPacket(ui.PointerDataPacket(data: <ui.PointerData>[
       _pointerData(PointerChange.hover, const Offset(0.0, 10.0)),
     ]));
-    expect(logs, <String>['enterA', 'enterB', 'hoverA', 'hoverB']);
+    expect(logs, <String>['enterA', 'enterB', 'hoverB', 'hoverA']);
     logs.clear();
 
     // Moves out of A within one frame.

packages/flutter/test/rendering/mouse_tracking_test_utils.dart

@@ -77,7 +77,6 @@ class TestAnnotationTarget with Diagnosticable implements MouseTrackerAnnotation
   @override
   final PointerEnterEventListener? onEnter;
 
-  @override
   final PointerHoverEventListener? onHover;
 
   @override

packages/flutter/test/rendering/platform_view_test.dart

@@ -87,6 +87,19 @@ void main() {
       expect(fakePlatformViewController.dispatchedPointerEvents, isNotEmpty);
     });
 
+    test('touch hover events are dispatched via PlatformViewController.dispatchPointerEvent', () {
+      layout(platformViewRenderBox);
+      pumpFrame(phase: EnginePhase.flushSemantics);
+
+      ui.window.onPointerDataPacket(ui.PointerDataPacket(data: <ui.PointerData>[
+        _pointerData(ui.PointerChange.add, const Offset(0, 0)),
+        _pointerData(ui.PointerChange.hover, const Offset(10, 10)),
+        _pointerData(ui.PointerChange.remove, const Offset(10, 10)),
+      ]));
+
+      expect(fakePlatformViewController.dispatchedPointerEvents, isNotEmpty);
+    });
+
   }, skip: isBrowser); // TODO(yjbanov): fails on Web with obscured stack trace: https://github.com/flutter/flutter/issues/42770
 }
 

packages/flutter/test/widgets/listener_test.dart

@@ -49,6 +49,34 @@ void main() {
     ]));
   });
 
+  testWidgets('Detects hover events from touch devices', (WidgetTester tester) async {
+    final List<String> log = <String>[];
+
+    await tester.pumpWidget(
+      Center(
+        child: SizedBox(
+          width: 300,
+          height: 300,
+          child: Listener(
+            onPointerHover: (_) {
+              log.add('bottom');
+            },
+            child: const Text('X', textDirection: TextDirection.ltr),
+          ),
+        ),
+      ),
+    );
+
+    final TestGesture gesture = await tester.createGesture();
+    await gesture.addPointer();
+    addTearDown(gesture.removePointer);
+    await gesture.moveTo(tester.getCenter(find.byType(Listener)));
+
+    expect(log, equals(<String>[
+      'bottom',
+    ]));
+  });
+
   group('transformed events', () {
     testWidgets('simple offset for touch/signal', (WidgetTester tester) async {
       final List<PointerEvent> events = <PointerEvent>[];

packages/flutter/test/widgets/mouse_region_test.dart

@@ -125,7 +125,8 @@ void main() {
     PointerExitEvent exit;
     await tester.pumpWidget(Center(
       child: MouseRegion(
-        child: const SizedBox(
+        child: Container(
+          color: const Color.fromARGB(0xff, 0xff, 0x00, 0x00),
           width: 100.0,
           height: 100.0,
         ),
@@ -372,6 +373,37 @@ void main() {
     expect(exit.localPosition, equals(const Offset(50, 50)));
   });
 
+  testWidgets('detects hover from touch devices', (WidgetTester tester) async {
+    PointerEnterEvent enter;
+    PointerHoverEvent move;
+    PointerExitEvent exit;
+    await tester.pumpWidget(Center(
+      child: MouseRegion(
+        child: Container(
+          color: const Color.fromARGB(0xff, 0xff, 0x00, 0x00),
+          width: 100.0,
+          height: 100.0,
+        ),
+        onEnter: (PointerEnterEvent details) => enter = details,
+        onHover: (PointerHoverEvent details) => move = details,
+        onExit: (PointerExitEvent details) => exit = details,
+      ),
+    ));
+    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.touch);
+    await gesture.addPointer(location: Offset.zero);
+    addTearDown(gesture.removePointer);
+    await tester.pump();
+    move = null;
+    enter = null;
+    exit = null;
+    await gesture.moveTo(const Offset(400.0, 300.0));
+    expect(move, isNotNull);
+    expect(move.position, equals(const Offset(400.0, 300.0)));
+    expect(move.localPosition, equals(const Offset(50.0, 50.0)));
+    expect(enter, isNull);
+    expect(exit, isNull);
+  });
+
   testWidgets('Hover works with nested listeners', (WidgetTester tester) async {
     final UniqueKey key1 = UniqueKey();
     final UniqueKey key2 = UniqueKey();
@@ -589,8 +621,12 @@ void main() {
     }
 
     await tester.pumpWidget(hoverableContainer(
-      onEnter: (PointerEnterEvent details) { logs.add('enter1'); },
-      onHover: (PointerHoverEvent details) { logs.add('hover1'); },
+      onEnter: (PointerEnterEvent details) {
+        logs.add('enter1');
+      },
+      onHover: (PointerHoverEvent details) {
+        logs.add('hover1');
+      },
       onExit: (PointerExitEvent details) { logs.add('exit1'); },
     ));
 
@@ -1178,31 +1214,31 @@ void main() {
       // Move to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['enterA', 'enterB', 'enterC', 'hoverA', 'hoverB', 'hoverC']);
+      expect(logs, <String>['enterA', 'enterB', 'enterC', 'hoverC', 'hoverB', 'hoverA']);
       logs.clear();
 
       // Move to the B only area.
       await gesture.moveTo(const Offset(25, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['exitC', 'hoverA', 'hoverB']);
+      expect(logs, <String>['exitC', 'hoverB', 'hoverA']);
       logs.clear();
 
       // Move back to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['enterC', 'hoverA', 'hoverB', 'hoverC']);
+      expect(logs, <String>['enterC', 'hoverC', 'hoverB', 'hoverA']);
       logs.clear();
 
       // Move to the C only area.
       await gesture.moveTo(const Offset(125, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['exitB', 'hoverA', 'hoverC']);
+      expect(logs, <String>['exitB', 'hoverC', 'hoverA']);
       logs.clear();
 
       // Move back to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['enterB', 'hoverA', 'hoverB', 'hoverC']);
+      expect(logs, <String>['enterB', 'hoverC', 'hoverB', 'hoverA']);
       logs.clear();
 
       // Move out.
@@ -1226,31 +1262,31 @@ void main() {
       // Move to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['enterA', 'enterC', 'hoverA', 'hoverC']);
+      expect(logs, <String>['enterA', 'enterC', 'hoverC', 'hoverA']);
       logs.clear();
 
       // Move to the B only area.
       await gesture.moveTo(const Offset(25, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['exitC', 'enterB', 'hoverA', 'hoverB']);
+      expect(logs, <String>['exitC', 'enterB', 'hoverB', 'hoverA']);
       logs.clear();
 
       // Move back to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['exitB', 'enterC', 'hoverA', 'hoverC']);
+      expect(logs, <String>['exitB', 'enterC', 'hoverC', 'hoverA']);
       logs.clear();
 
       // Move to the C only area.
       await gesture.moveTo(const Offset(125, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['hoverA', 'hoverC']);
+      expect(logs, <String>['hoverC', 'hoverA']);
       logs.clear();
 
       // Move back to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['hoverA', 'hoverC']);
+      expect(logs, <String>['hoverC', 'hoverA']);
       logs.clear();
 
       // Move out.
@@ -1274,7 +1310,7 @@ void main() {
       // Move to the overlapping area.
       await gesture.moveTo(const Offset(75, 75));
       await tester.pumpAndSettle();
-      expect(logs, <String>['enterA', 'enterC', 'hoverA', 'hoverC']);
+      expect(logs, <String>['enterA', 'enterC', 'hoverC', 'hoverA']);
       logs.clear();
 
       // Move out.

packages/flutter_test/lib/src/test_pointer.dart

@@ -25,11 +25,7 @@ class TestPointer {
     this.kind = PointerDeviceKind.touch,
     int? device,
     int buttons = kPrimaryButton,
-  ])
-      : assert(kind != null),
-        assert(pointer != null),
-        assert(buttons != null),
-        _buttons = buttons {
+  ]) : _buttons = buttons {
     switch (kind) {
       case PointerDeviceKind.mouse:
         _device = device ?? 1;
@@ -211,7 +207,6 @@ class TestPointer {
     Duration timeStamp = Duration.zero,
     Offset? location,
   }) {
-    assert(timeStamp != null);
     _location = location ?? _location;
     return PointerAddedEvent(
       timeStamp: timeStamp,
@@ -230,7 +225,6 @@ class TestPointer {
     Duration timeStamp = Duration.zero,
     Offset? location,
   }) {
-    assert(timeStamp != null);
     _location = location ?? _location;
     return PointerRemovedEvent(
       timeStamp: timeStamp,
@@ -251,13 +245,10 @@ class TestPointer {
     Offset newLocation, {
     Duration timeStamp = Duration.zero,
   }) {
-    assert(newLocation != null);
-    assert(timeStamp != null);
     assert(
         !isDown,
         'Hover events can only be generated when the pointer is up. To '
         'simulate movement when the pointer is down, use move() instead.');
-    assert(kind != PointerDeviceKind.touch, "Touch pointers can't generate hover events");
     final Offset delta = location != null ? newLocation - location! : Offset.zero;
     _location = newLocation;
     return PointerHoverEvent(
@@ -278,8 +269,6 @@ class TestPointer {
     Offset scrollDelta, {
     Duration timeStamp = Duration.zero,
   }) {
-    assert(scrollDelta != null);
-    assert(timeStamp != null);
     assert(kind != PointerDeviceKind.touch, "Touch pointers can't generate pointer signal events");
     assert(location != null);
     return PointerScrollEvent(
@@ -327,11 +316,7 @@ class TestGesture {
     PointerDeviceKind kind = PointerDeviceKind.touch,
     int? device,
     int buttons = kPrimaryButton,
-  }) : assert(dispatcher != null),
-       assert(pointer != null),
-       assert(kind != null),
-       assert(buttons != null),
-       _dispatcher = dispatcher,
+  }) : _dispatcher = dispatcher,
        _pointer = TestPointer(pointer, kind, device, buttons);
 
   /// Dispatch a pointer down event at the given `downLocation`, caching the
@@ -380,8 +365,7 @@ class TestGesture {
   /// Send a move event moving the pointer by the given offset.
   ///
   /// If the pointer is down, then a move event is dispatched. If the pointer is
-  /// up, then a hover event is dispatched. Touch devices are not able to send
-  /// hover events.
+  /// up, then a hover event is dispatched.
   Future<void> moveBy(Offset offset, { Duration timeStamp = Duration.zero }) {
     assert(_pointer.location != null);
     return moveTo(_pointer.location! + offset, timeStamp: timeStamp);
@@ -390,15 +374,12 @@ class TestGesture {
   /// Send a move event moving the pointer to the given location.
   ///
   /// If the pointer is down, then a move event is dispatched. If the pointer is
-  /// up, then a hover event is dispatched. Touch devices are not able to send
-  /// hover events.
+  /// up, then a hover event is dispatched.
   Future<void> moveTo(Offset location, { Duration timeStamp = Duration.zero }) {
     return TestAsyncUtils.guard<void>(() {
       if (_pointer._isDown) {
         return _dispatcher(_pointer.move(location, timeStamp: timeStamp));
       } else {
-        assert(_pointer.kind != PointerDeviceKind.touch,
-            'Touch device move events can only be sent if the pointer is down.');
         return _dispatcher(_pointer.hover(location, timeStamp: timeStamp));
       }
     });