test: Add GC lifecycle test for identity-cached wrappers#731
Merged
kateinoigakukun merged 1 commit intomainfrom Apr 28, 2026
Merged
test: Add GC lifecycle test for identity-cached wrappers#731kateinoigakukun merged 1 commit intomainfrom
kateinoigakukun merged 1 commit intomainfrom
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Verify that WeakRef-based identity cache does not prevent garbage collection. Creates an identity-mode object, crosses it 5 times (filling identity cache), drops all references, triggers GC + event loop ticks, and asserts the Swift object is deallocated and deinit fires exactly once.
kateinoigakukun
approved these changes
Apr 28, 2026
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Overview
Add a test verifying that the
WeakRef-based identity cache (introduced in #723) does not prevent garbage collection of Swift heap objects.The existing GC lifecycle test (
testJSWrapperIsDeallocatedAfterFinalizationinSwiftClassSupportTests) covers non-identity classes. This adds an equivalent for@JS(identityMode: true)classes where the identity cache holds aWeakRefto the wrapper.What it tests
Creates a
RetainLeakSubject(identity-mode class), crosses it to JS 5 times (filling the identity cache with aWeakRefentry), drops all Swift-side references, triggers GC + event loop ticks, and verifies:weakSubject == nil)deinitfires exactly onceThis covers the scenario where only JavaScript holds a reference to an identity-cached Swift object via
WeakRef, then that reference becomes unreachable.What changed
IdentityModeTests.swift— AddedtestIdentityCachedWrapperIsReclaimedByGCasync test. Added@JSFunction gc()import (same pattern asSwiftClassSupportTests).Generated/BridgeJS.swift+Generated/JavaScript/BridgeJS.json— Regenerated to includegcimport binding.