`CupertinoSwitch`: Add clickable cursor for web (#99554)

packages/flutter/lib/src/cupertino/switch.dart

@@ -298,19 +298,22 @@ class _CupertinoSwitchState extends State<CupertinoSwitch> with TickerProviderSt
   Widget build(BuildContext context) {
     if (needsPositionAnimation)
       _resumePositionAnimation();
-    return Opacity(
-      opacity: widget.onChanged == null ? _kCupertinoSwitchDisabledOpacity : 1.0,
-      child: _CupertinoSwitchRenderObjectWidget(
-        value: widget.value,
-        activeColor: CupertinoDynamicColor.resolve(
-          widget.activeColor ?? CupertinoColors.systemGreen,
-          context,
+    return MouseRegion(
+      cursor: isInteractive && kIsWeb ? SystemMouseCursors.click : MouseCursor.defer,
+      child: Opacity(
+        opacity: widget.onChanged == null ? _kCupertinoSwitchDisabledOpacity : 1.0,
+        child: _CupertinoSwitchRenderObjectWidget(
+          value: widget.value,
+          activeColor: CupertinoDynamicColor.resolve(
+            widget.activeColor ?? CupertinoColors.systemGreen,
+            context,
+          ),
+          trackColor: CupertinoDynamicColor.resolve(widget.trackColor ?? CupertinoColors.secondarySystemFill, context),
+          thumbColor: CupertinoDynamicColor.resolve(widget.thumbColor ?? CupertinoColors.white, context),
+          onChanged: widget.onChanged,
+          textDirection: Directionality.of(context),
+          state: this,
         ),
-        trackColor: CupertinoDynamicColor.resolve(widget.trackColor ?? CupertinoColors.secondarySystemFill, context),
-        thumbColor: CupertinoDynamicColor.resolve(widget.thumbColor ?? CupertinoColors.white, context),
-        onChanged: widget.onChanged,
-        textDirection: Directionality.of(context),
-        state: this,
       ),
     );
   }

packages/flutter/test/cupertino/switch_test.dart

@@ -7,8 +7,10 @@
 @Tags(<String>['reduced-test-set'])
 
 import 'package:flutter/cupertino.dart';
+import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
 
@@ -761,4 +763,61 @@ void main() {
       matchesGoldenFile('switch.tap.on.dark.png'),
     );
   });
+
+  testWidgets('Hovering over Cupertino switch updates cursor to clickable on Web', (WidgetTester tester) async {
+    const bool value = false;
+    // Disabled CupertinoSwitch does not update cursor on Web.
+    await tester.pumpWidget(
+      Directionality(
+        textDirection: TextDirection.ltr,
+        child: StatefulBuilder(
+          builder: (BuildContext context, StateSetter setState) {
+            return const Center(
+              child: CupertinoSwitch(
+                value: value,
+                dragStartBehavior: DragStartBehavior.down,
+                onChanged: null,
+              ),
+            );
+          },
+        ),
+      ),
+    );
+
+    final TestGesture gesture = await tester.createGesture(kind: PointerDeviceKind.mouse, pointer: 1);
+    final Offset cupertinoSwitch = tester.getCenter(find.byType(CupertinoSwitch));
+    await gesture.addPointer(location: cupertinoSwitch);
+    await tester.pumpAndSettle();
+    expect(RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1), SystemMouseCursors.basic);
+
+    // Enabled CupertinoSwitch updates cursor when hovering on Web.
+    await tester.pumpWidget(
+      Directionality(
+        textDirection: TextDirection.ltr,
+        child: StatefulBuilder(
+          builder: (BuildContext context, StateSetter setState) {
+            return Center(
+              child: CupertinoSwitch(
+                value: value,
+                dragStartBehavior: DragStartBehavior.down,
+                onChanged: (bool newValue) { },
+              ),
+            );
+          },
+        ),
+      ),
+    );
+
+    await gesture.moveTo(const Offset(10, 10));
+    await tester.pumpAndSettle();
+    expect(RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1), SystemMouseCursors.basic);
+
+    await gesture.moveTo(cupertinoSwitch);
+    addTearDown(gesture.removePointer);
+    await tester.pumpAndSettle();
+    expect(
+      RendererBinding.instance.mouseTracker.debugDeviceActiveCursor(1),
+      kIsWeb ? SystemMouseCursors.click : SystemMouseCursors.basic,
+    );
+  });
 }