From d57ea48ca1b7f60f549e7ade4b0d698509ca659a Mon Sep 17 00:00:00 2001
From: LongCatIsLooong <31859944+LongCatIsLooong@users.noreply.github.com>
Date: Wed, 22 May 2024 14:25:31 -0700
Subject: [PATCH] Remove an assert with false positives (#148795)

Fixes https://github.com/flutter/flutter/issues/110343.

This is not an important piece of guardrail and the iOS embedder only expects best-effort results anyways.
---
 .../lib/src/widgets/editable_text.dart        |  1 -
 .../test/widgets/editable_text_test.dart      | 31 +++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)

diff --git a/packages/flutter/lib/src/widgets/editable_text.dart b/packages/flutter/lib/src/widgets/editable_text.dart
index 069230666e9f..08487b5d2af0 100644
--- a/packages/flutter/lib/src/widgets/editable_text.dart
+++ b/packages/flutter/lib/src/widgets/editable_text.dart
@@ -4494,7 +4494,6 @@ class EditableTextState extends State<EditableText> with AutomaticKeepAliveClien
     Rect? composingRect = renderEditable.getRectForComposingRange(composingRange);
     // Send the caret location instead if there's no marked text yet.
     if (composingRect == null) {
-      assert(!composingRange.isValid || composingRange.isCollapsed);
       final int offset = composingRange.isValid ? composingRange.start : 0;
       composingRect = renderEditable.getLocalRectForCaret(TextPosition(offset: offset));
     }
diff --git a/packages/flutter/test/widgets/editable_text_test.dart b/packages/flutter/test/widgets/editable_text_test.dart
index 8c031c4a17ff..ab260f8a3cf6 100644
--- a/packages/flutter/test/widgets/editable_text_test.dart
+++ b/packages/flutter/test/widgets/editable_text_test.dart
@@ -17548,6 +17548,37 @@ void main() {
       const TextSelection.collapsed(offset: 17, affinity: TextAffinity.upstream),
     );
   });
+
+  testWidgets('Composing region can truncate grapheme', (WidgetTester tester) async {
+    await tester.pumpWidget(
+      MediaQuery(
+        data: const MediaQueryData(),
+        child: Directionality(
+          textDirection: TextDirection.ltr,
+          child: EditableText(
+            autofocus: true,
+            backgroundCursorColor: Colors.grey,
+            controller: controller,
+            focusNode: focusNode,
+            style: textStyle,
+            cursorColor: cursorColor,
+          ),
+        ),
+      ),
+    );
+
+    await tester.pumpAndSettle();
+    assert(focusNode.hasFocus);
+
+    controller.value = const TextEditingValue(
+      text: 'Á',
+      selection: TextSelection(baseOffset: 1, extentOffset: 2),
+      composing: TextSelection(baseOffset: 1, extentOffset: 2),
+    );
+    await tester.pumpAndSettle();
+
+    expect(tester.takeException(), isNull);
+  });
 }
 
 class UnsettableController extends TextEditingController {