Fix re-entrant resolve deadlock (issue #4)#6
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Calling `pod.resolve()` from within a provider builder that holds a reference to the same `SwiftiePod` instance (e.g. via a global `Log` shim) caused a deadlock: the outer `resolve` held `dispatchQueue` via `sync`, and the inner resolve attempted another `sync` on the same serial queue. Fix: use `DispatchSpecificKey` to mark the queue context. Before calling `dispatchQueue.sync`, check whether the current execution context is already on the queue. If so, invoke the resolver directly — the serial queue guarantees exclusive access, so this is safe. Also adds `ReentrantResolveTests.swift` with three tests that cover the safe path (using the passed-in resolver), the direct re-entrant path from the issue reproduction, and the real-world Log-shim scenario. https://claude.ai/code/session_017ztecAXmWm6cLm5rmPuAX2
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Calling
pod.resolve()from within a provider builder that holds areference to the same
SwiftiePodinstance (e.g. via a globalLogshim) caused a deadlock: the outer
resolvehelddispatchQueueviasync, and the inner resolve attempted anothersyncon the sameserial queue.
Fix: use
DispatchSpecificKeyto mark the queue context. Beforecalling
dispatchQueue.sync, check whether the current executioncontext is already on the queue. If so, invoke the resolver directly
— the serial queue guarantees exclusive access, so this is safe.
Also adds
ReentrantResolveTests.swiftwith three tests that coverthe safe path (using the passed-in resolver), the direct re-entrant
path from the issue reproduction, and the real-world Log-shim scenario.