Release Notes - xcsift v1.0.8

🚀 Performance & Bug Fixes

Fixed: Stdin Hanging on Large Files

Previously, xcsift would hang indefinitely when processing large build output files (2+ MB) piped through stdin. This release completely fixes this issue with two key improvements:

Stdin Reading Fix:

• Replaced custom polling-based stdin reading logic with proper FileHandle.readToEnd() API
• Now correctly handles EOF signals when reading from pipes
• Supports both modern macOS (10.15.4+) and older systems with appropriate fallbacks

Parser Performance Optimization:

• Added fast-path string filtering before regex matching to avoid catastrophic backtracking
• Optimized line splitting using split(separator:) instead of components(separatedBy:)
• Filters out irrelevant lines (empty, too long, or without error/test keywords) before expensive regex operations
• Parser now handles large files (8000+ lines, 2.6MB) in ~0.6 seconds instead of hanging indefinitely

Testing

• Added comprehensive unit test with real-world 2.6MB build output fixture (8101 lines)
• Test validates both correctness and performance (regression test for the hang fix)
• All existing tests continue to pass

Technical Details

The hang was caused by two issues:

1. Custom stdin reading used availableData with sleep delays, which didn't properly detect EOF on piped input
2. Regex patterns with OneOrMore(.any, .reluctant) caused catastrophic backtracking on lines that didn't match

Both issues are now resolved, making xcsift production-ready for processing large Xcode build outputs.

Installation

Homebrew

brew upgrade ldomaradzki/xcsift/xcsift

Manual

git clone https://github.com/ldomaradzki/xcsift.git
cd xcsift
swift build -c release
cp .build/release/xcsift /usr/local/bin/

Full Changelog

• Fixed: Stdin reading hangs on large files when piped through cat or similar commands
• Fixed: Parser performance issues with large build outputs
• Added: Real-world 2.6MB build output fixture for testing
• Improved: Line parsing performance with fast-path filtering
• Improved: Stdin reading using proper EOF-aware APIs

Full Diff: v1.0.7...v1.0.8