fix: non-blocking ShellExecutor — deadlock-safe, with tests#11
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…implementation Three bugs fixed: 1. `waitUntilExit()` blocked Swift's cooperative thread pool — replaced with `withCheckedThrowingContinuation` + `terminationHandler` so no thread is held while waiting for the subprocess. 2. Timeout error was silently swallowed — the throw inside the old timeout `Task` never escaped to the caller. Now both the termination handler and the timeout race via `OSAllocatedUnfairLock<Bool>`; first one wins and resumes the continuation correctly. 3. Pipe buffer deadlock — `readDataToEndOfFile()` after `waitUntilExit()` deadlocks if output exceeds ~64 KB. Fixed with `readabilityHandler` draining into `OSAllocatedUnfairLock<Data>` buffers as data arrives. Also converts `actor ShellExecutor` to `final class` so concurrent `execute()` calls across multiple users can run in true parallel rather than serializing through the actor. Co-Authored-By: Buqian Zheng <zhengbuqian@gmail.com>
…tterns, add ShellExecutor tests - Cancel the timeout Task via OSAllocatedUnfairLock<Task?> when terminationHandler fires so it doesn't linger for the full timeout duration after fast commands - Extract networkErrorPatterns to a static constant; was duplicated between execute() and checkGHAuthenticated(), with "failed to connect" missing from the latter - Make parseHosts internal (was private) so @testable import can reach it - Add ShellExecutorTests: 6 parseHosts unit tests + 1 timeout integration test - Fix pre-existing Swift 6 build errors in PRMonitorViewModelTests: add @mainactor to ParsePRURLTests, OtherPRsServiceTests, PRTypeDisplayTitleTests, and CustomNamesServiceTests (all test @MainActor-inferred types) Co-Authored-By: Buqian Zheng <zhengbuqian@users.noreply.github.com> Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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Summary
Ports the
ShellExecutorrewrite from PR #8 (credit: @zhengbuqian) with additional fixes and test coverage identified during review.What the original rewrite fixed (from #8):
waitUntilExit()blocked Swift's cooperative thread pool → replaced withterminationHandler+withCheckedThrowingContinuationreadabilityHandlerstreams data incrementally viaOSAllocatedUnfairLock<Data>actor ShellExecutorserialized concurrent task-group calls → converted tofinal classfor true parallelismAdditional fixes in this PR:
Taskwas never cancelled after normal process exit — leaked for the full timeout duration (30s by default). Fixed viaOSAllocatedUnfairLock<Task<Void, Never>?>soterminationHandlercancels it immediately.networkErrorPatternswas duplicated betweenexecute()andcheckGHAuthenticated(), and"failed to connect"was missing from the latter copy. Extracted to a singlestatic let.PRMonitorViewModelTests: four test structs were calling@MainActor-inferred types from non-isolated contexts. Added@MainActortoParsePRURLTests,OtherPRsServiceTests,PRTypeDisplayTitleTests, andCustomNamesServiceTests.Test plan
ShellExecutorTestssuite: 6parseHostsunit tests + 1 timeout integration test (sleep 10with 0.1s timeout assertsexecutionFailed("…timed out…"))Attribution
Core
ShellExecutorrewrite originally authored by @zhengbuqian in #8.🤖 Generated with Claude Code