Fix NSRangeException crash in TextInput delegate adapters#55950
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lukeharvey wants to merge 1 commit intofacebook:mainfrom
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Fix NSRangeException crash in TextInput delegate adapters#55950lukeharvey wants to merge 1 commit intofacebook:mainfrom
lukeharvey wants to merge 1 commit intofacebook:mainfrom
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Summary:
The existing range guard in the UITextView delegate (added in #24084) only checks range.location + range.length > text.length. It doesn't handle range.location > text.length, which causes an unsigned integer underflow in the clamped length, still crashing with NSRangeException. See #45050 for another report of this.
The UITextField delegate has no range validation at all.
This PR adds a range.location > textLength early return to both delegate adapters, ahead of the existing length clamping.
Changelog:
[IOS] [FIXED] - Fix NSRangeException crash in RCTBackedTextInputDelegateAdapter when text range is out of bounds
Test Plan:
This is a race condition between iOS computing the text range and React Native updating the backing text (e.g. controlled TextInput state updates, maxLength truncation, autocorrect). It's difficult to reproduce deterministically but shows up in production crash logs. The fix is straightforward defensive bounds checking before calling replaceCharactersInRange:.