Fix flaky testCardArtImage_returnsNilWhenImageNotCached test 🪿✨ - #6872
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Fix flaky testCardArtImage_returnsNilWhenImageNotCached test 🪿✨#6872joyceqin-stripe wants to merge 1 commit into
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When DownloadManager is initialized with isTesting: false (the default), it overrides the provided URLSessionConfiguration's urlCache with a disk-backed URLCache at a fixed path. This caused test ordering flakiness: testCardArtImage_returnsImageWhenCached seeds the disk cache, and a subsequent testCardArtImage_returnsNilWhenImageNotCached may read that stale disk data before removeAllCachedResponses() fully completes. Pass isTesting: true so the DownloadManager uses the explicit memory-only URLCache (diskCapacity: 0) the test sets up, eliminating the disk I/O race condition. Committed-By-Agent: goose
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August 7, 2026 19:57
joyceqin-stripe
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Minion run
Summary
Pass
isTesting: truewhen constructingDownloadManagerinSTPPaymentMethodCardArtImageTest.setUp()so the manager uses the test's explicit memory-onlyURLCacheinstead of a disk-backed one.Motivation
testCardArtImage_returnsNilWhenImageNotCachedwas flaky becauseDownloadManager.init(withisTesting: false, the default) unconditionally replaces the providedURLSessionConfiguration'surlCachewith a disk-backedURLCacheat a fixedSTPCachepath — discarding the memory-only cache the test configured. WhentestCardArtImage_returnsImageWhenCachedran first, it seeded image data to that shared disk cache. A subsequent run oftestCardArtImage_returnsNilWhenImageNotCachedwould create a newURLCachepointing to the same path, andURLCache.removeAllCachedResponses()(called inresetCache()) does not guarantee synchronous disk removal, sopromoteFromDiskCachecould still find and return the stale image — causing theXCTAssertNilto fail.Passing
isTesting: trueskips the disk cache setup entirely. TheDownloadManagerthen uses theURLCache(memoryCapacity: 5_000_000, diskCapacity: 0)already set on the config, eliminating the disk I/O race.Testing
Existing tests in
STPPaymentMethodCardArtImageTestcover the fix —testCardArtImage_returnsNilWhenImageNotCached(previously flaky) andtestCardArtImage_returnsImageWhenCached(verifies the positive case still works with the memory cache seeded viaseedURLCache).No tests were newly ignored.
Changelog
No user-facing change.