Add mouseCursor to Tooltip (#159922)

Part of flutter/flutter#58192

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---------

Co-authored-by: Bruno Leroux <bruno.leroux@gmail.com>

Author: ValentinVignal

packages/flutter/lib/src/material/tooltip.dart

@@ -46,6 +46,7 @@ class _ExclusiveMouseRegion extends MouseRegion {
   const _ExclusiveMouseRegion({
     super.onEnter,
     super.onExit,
+    super.cursor,
     super.child,
   });
 
@@ -54,6 +55,7 @@ class _ExclusiveMouseRegion extends MouseRegion {
     return _RenderExclusiveMouseRegion(
       onEnter: onEnter,
       onExit: onExit,
+      cursor: cursor,
     );
   }
 }
@@ -62,6 +64,7 @@ class _RenderExclusiveMouseRegion extends RenderMouseRegion {
   _RenderExclusiveMouseRegion({
     super.onEnter,
     super.onExit,
+    super.cursor,
   });
 
   static bool isOutermostMouseRegion = true;
@@ -195,6 +198,7 @@ class Tooltip extends StatefulWidget {
     this.triggerMode,
     this.enableFeedback,
     this.onTriggered,
+    this.mouseCursor,
     this.child,
   }) :  assert((message == null) != (richMessage == null), 'Either `message` or `richMessage` must be specified'),
         assert(
@@ -363,6 +367,12 @@ class Tooltip extends StatefulWidget {
   /// or after a long press when [triggerMode] is [TooltipTriggerMode.longPress].
   final TooltipTriggeredCallback? onTriggered;
 
+  /// The cursor for a mouse pointer when it enters or is hovering over the
+  /// widget.
+  ///
+  /// If this property is null, [MouseCursor.defer] will be used.
+  final MouseCursor? mouseCursor;
+
   static final List<TooltipState> _openedTooltips = <TooltipState>[];
 
   /// Dismiss all of the tooltips that are currently shown on the screen,
@@ -839,6 +849,7 @@ class TooltipState extends State<Tooltip> with SingleTickerProviderStateMixin {
       result = _ExclusiveMouseRegion(
         onEnter: _handleMouseEnter,
         onExit: _handleMouseExit,
+        cursor: widget.mouseCursor ?? MouseCursor.defer,
         child: Listener(
           onPointerDown: _handlePointerDown,
           behavior: HitTestBehavior.opaque,

packages/flutter/test/material/tooltip_test.dart

@@ -3091,6 +3091,38 @@ void main() {
 
     expect(selectedText, isNot(contains('A')));
   });
+
+  testWidgets('Tooltip mouse cursor behavior', (WidgetTester tester) async {
+    const SystemMouseCursor customCursor = SystemMouseCursors.grab;
+
+    await tester.pumpWidget(
+      const MaterialApp(
+        home: Center(
+          child: Tooltip(
+            message: tooltipText,
+            mouseCursor: customCursor,
+            child: SizedBox.square(dimension: 50),
+          ),
+        ),
+      ),
+    );
+
+    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse, pointer: 1);
+    await gesture.addPointer(location: const Offset(10, 10));
+    await tester.pump();
+    expect(
+      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
+      SystemMouseCursors.basic,
+    );
+
+    final Offset chip = tester.getCenter(find.byType(Tooltip));
+    await gesture.moveTo(chip);
+    await tester.pump();
+    expect(
+      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
+      customCursor,
+    );
+  });
 }
 
 Future<void> setWidgetForTooltipMode(