Fix emoji insertion corruption by using grapheme-aware text operations#183112
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Istiak-Ahmed78 wants to merge 6 commits intoflutter:masterfrom
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Fix emoji insertion corruption by using grapheme-aware text operations#183112Istiak-Ahmed78 wants to merge 6 commits intoflutter:masterfrom
Istiak-Ahmed78 wants to merge 6 commits intoflutter:masterfrom
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- Update TextEditingValue.replaced() to use grapheme cluster boundaries instead of UTF-16 code unit positions to prevent splitting surrogate pairs - Add TextInput._validateAndCorrectTextEditingValue() to detect and fix broken surrogate pairs received from the Android IME - Intercept platform text updates in _handleTextInputInvocation() to apply corrections before updating the text input client Fixes flutter#181759
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This pull request introduces a grapheme-aware text replacement logic and a correction mechanism for broken surrogate pairs from the Android IME, which effectively fixes the emoji insertion issue. The changes are well-tested. My review includes a couple of suggestions: one to improve the performance of the grapheme boundary calculation in TextEditingValue.replaced, and another to fix a potential bug in the logic for identifying the inserted character in _validateAndCorrectTextEditingValue.
…/Istiak-Ahmed78/flutter into fix/emoji-surrogate-pair-android
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Mar 2, 2026
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All suggestions are applied. Ready to be merged
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Fixes a bug where inserting emojis between existing emojis in an RTL
TextFieldon Android would break the text and render?characters. The root cause was that the Android IME sends text updates using UTF-16 code unit positions, which can split surrogate pairs when the cursor is placed between emoji characters.Changes made:
TextEditingValue.replaced()— Updated to use grapheme cluster boundaries instead of raw UTF-16 code unit positions, preventing surrogate pair splits during text replacement.TextInput._validateAndCorrectTextEditingValue()— New method that detects and fixes broken surrogate pairs received from the Android IME before they reach the text input client._handleTextInputInvocation()— Now intercepts platform text updates and applies the correction above before forwarding to the text input client.Before / After:
?and breaks text543327209-706052f5-2309-4bdf-a44b-6ab05848f8a7.mp4
IMG_20260302_154756_666.mp4
Fixes #181759
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