fix: Fix critical deadlock and hanging issues in async processors - #311
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## Changes Made: ### 1. Fixed cancellation handling in EnumerableExtensions - Added proper CancellationToken support to ToIAsyncEnumerable method - While loop now properly responds to cancellation requests - Prevents infinite hanging when tasks don't complete ### 2. Fixed semaphore release bug in ParallelExtensions - Only releases semaphore if it was successfully acquired - Prevents SemaphoreFullException when cancellation occurs during WaitAsync - Tracks acquisition state properly in both ProcessAsync overloads ### 3. Removed unnecessary Task.Run wrapping - Eliminated redundant Task.Run in rate-limited processors - Removed Task.Run wrapping for already-async operations in ParallelExtensions - Fixed Task.Run + Task.Yield redundancy (just using Task.Yield where needed) ### 4. Improved unbounded processor implementations - AsyncEnumerableUnboundedParallelProcessor now truly unbounded (no artificial limits) - Trusts .NET ThreadPool to manage resources appropriately - Enhanced documentation warnings about resource risks - Maintains backward compatibility ### 5. Performance improvements - Removed wasteful counting/enumeration operations - Eliminated double context switching from Task.Run + Task.Yield - Let runtime handle thread pool scheduling optimally These fixes address the critical issues identified in the deadlock analysis while maintaining the library's performance characteristics and backward compatibility. 🤖 Generated with [Claude Code](https://claude.ai/code) Co-Authored-By: Claude <noreply@anthropic.com>
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Changes Made:
1. Fixed cancellation handling in EnumerableExtensions
2. Fixed semaphore release bug in ParallelExtensions
3. Removed unnecessary Task.Run wrapping
4. Improved unbounded processor implementations
5. Performance improvements
These fixes address the critical issues identified in the deadlock analysis while maintaining the library's performance characteristics and backward compatibility.
🤖 Generated with Claude Code