Clear _scribbleCacheKey when connection closes (#122145)

Clear _scribbleCacheKey when connection closes

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

@@ -3165,6 +3165,7 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
       _textInputConnection!.close();
       _textInputConnection = null;
       _lastKnownRemoteTextEditingValue = null;
+      _scribbleCacheKey = null;
       removeTextPlaceholder();
     }
   }

packages/flutter/test/widgets/editable_text_test.dart

@@ -852,6 +852,87 @@ void main() {
     expect(focusNode.hasFocus, isFalse);
   });
 
+  testWidgets('selection rects re-sent when refocused', (WidgetTester tester) async {
+    final List<List<SelectionRect>> log = <List<SelectionRect>>[];
+    SystemChannels.textInput.setMockMethodCallHandler((MethodCall methodCall) async {
+      if (methodCall.method == 'TextInput.setSelectionRects') {
+        final List<dynamic> args = methodCall.arguments as List<dynamic>;
+        final List<SelectionRect> selectionRects = <SelectionRect>[];
+        for (final dynamic rect in args) {
+          selectionRects.add(SelectionRect(
+            position: (rect as List<dynamic>)[4] as int,
+            bounds: Rect.fromLTWH(rect[0] as double, rect[1] as double, rect[2] as double, rect[3] as double),
+          ));
+        }
+        log.add(selectionRects);
+      }
+    });
+
+    final TextEditingController controller = TextEditingController();
+    final ScrollController scrollController = ScrollController();
+    controller.text = 'Text1';
+
+    Future<void> pumpEditableText({ double? width, double? height, TextAlign textAlign = TextAlign.start }) async {
+      await tester.pumpWidget(
+        MediaQuery(
+          data: const MediaQueryData(),
+          child: Directionality(
+            textDirection: TextDirection.ltr,
+            child: Center(
+              child: SizedBox(
+                width: width,
+                height: height,
+                child: EditableText(
+                  controller: controller,
+                  textAlign: textAlign,
+                  scrollController: scrollController,
+                  maxLines: null,
+                  focusNode: focusNode,
+                  cursorWidth: 0,
+                  style: Typography.material2018().black.titleMedium!,
+                  cursorColor: Colors.blue,
+                  backgroundCursorColor: Colors.grey,
+                ),
+              ),
+            ),
+          ),
+        ),
+      );
+    }
+
+    const List<SelectionRect> expectedRects = <SelectionRect>[
+      SelectionRect(position: 0, bounds: Rect.fromLTRB(0.0, 0.0, 14.0, 14.0)),
+      SelectionRect(position: 1, bounds: Rect.fromLTRB(14.0, 0.0, 28.0, 14.0)),
+      SelectionRect(position: 2, bounds: Rect.fromLTRB(28.0, 0.0, 42.0, 14.0)),
+      SelectionRect(position: 3, bounds: Rect.fromLTRB(42.0, 0.0, 56.0, 14.0)),
+      SelectionRect(position: 4, bounds: Rect.fromLTRB(56.0, 0.0, 70.0, 14.0))
+    ];
+
+    await pumpEditableText();
+    expect(log, isEmpty);
+
+    await tester.showKeyboard(find.byType(EditableText));
+    // First update.
+    expect(log.single, expectedRects);
+    log.clear();
+
+    await tester.pumpAndSettle();
+    expect(log, isEmpty);
+
+    focusNode.unfocus();
+    await tester.pumpAndSettle();
+    expect(log, isEmpty);
+
+    focusNode.requestFocus();
+    //await tester.showKeyboard(find.byType(EditableText));
+    await tester.pumpAndSettle();
+    // Should re-receive the same rects.
+    expect(log.single, expectedRects);
+    log.clear();
+
+    // On web, we should rely on the browser's implementation of Scribble, so we will not send selection rects.
+  }, skip: kIsWeb, variant: const TargetPlatformVariant(<TargetPlatform>{ TargetPlatform.iOS })); // [intended]
+
   testWidgets('EditableText does not derive selection color from DefaultSelectionStyle', (WidgetTester tester) async {
     // Regression test for https://github.com/flutter/flutter/issues/103341.
     const TextEditingValue value = TextEditingValue(