Crash on macOS 15.x when rendering rename-only diff in Diff view (NSAttributedString range exception) #2740
Description
Environment
- App: GitUp 1.4.3 (1052)
- OS: macOS 15.7.3 (24G419)
- Architecture: x86_64 (Intel)
- Hardware: MacBookPro16,2
Summary
GitUp intermittently crashes on macOS 15.x when performing a rename-only operation and GitUp attempts to render the diff.
The crash occurs on the main thread while rendering the Diff view and is caused by an uncaught Objective-C exception inside NSConcreteMutableAttributedString.
This is not a Git repository corruption issue and does not occur when using git directly in the terminal.
Crash signature
The crash is consistent across multiple reports and always shows the same backtrace:
- Foundation -[NSMutableRLEArray replaceObjectsInRange:withObject:length:] -[NSConcreteMutableAttributedString setAttributes:range:]
- GitUpKit -[GIDiffContentsViewController tableView:viewForTableColumn:row:]
- AppKit -[NSApplication _crashOnException:]
The process terminates with EXC_BAD_INSTRUCTION (SIGILL) after AppKit forcefully aborts due to the uncaught exception.
Key observations
- The operation is a rename-only change (no content changes).
- The rename frequently involves files under a dot-prefixed directory (e.g. .Inbox), but the directory name itself is not required to trigger the crash.
- The issue does not occur every time. It appears to depend on the Diff view state and timing.
- The crash happens when GitUp refreshes or renders the Diff view after the rename.
- The same rename operation works reliably using git mv + git commit in the terminal.
This suggests a UI rendering issue rather than a Git data issue.