Fix race condition in dependency archive creation#76
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archiveDependencyTargets deleted libDep.a before recreating it with ar. When two CLI tests ran concurrently (snapshot + variants suites), the delete-then-recreate window allowed a concurrent compileCombined call to see the archive as missing, causing "ld: library 'LocalDep' not found". Fix: write to a temp file and atomically rename via replaceItemAt, so the archive is never absent from the linker's perspective. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Address review feedback: - UUID-based temp filename prevents collisions between concurrent callers - replaceItemAt errors are propagated, with moveItem fallback for first build - Removes stale-temp cleanup that could delete another caller's file Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Fixes intermittent CI failure:
ld: library 'LocalDep' not foundduring CLI integration tests.Root Cause
archiveDependencyTargetsdeletedlibDep.abefore recreating it withar rcs. TheCLI snapshot commandandCLI variants commandtest suites run in parallel — when a snapshot test calleddetectAndBuild(which re-archives dependencies) while the variants test was between its first and secondcompileCombinedcalls, the linker saw the archive as missing during the delete-to-recreate window.The race was exposed by #74's progress reporting, which adds small
awaitpauses between operations, widening the timing window.Fix
Write to a temp file (
libDep.a.tmp) and atomically rename viaFileManager.replaceItemAt, so the archive is never absent from the linker's perspective.Test plan
swift buildsucceedspreviewsmcp variants --variant light --variant darkproduces both images🤖 Generated with Claude Code