// META: script=/common/gc.js // META: script=resources/maybe-garbage-collect.js // ├──> maybeGarbageCollectAndCleanupAsync // └──> resolveGarbageCollection /*--- esid: sec-finalization-registry.prototype.cleanupSome info: | FinalizationRegistry.prototype.cleanupSome ( [ callback ] ) 1. Let finalizationRegistry be the this value. 2. If Type(finalizationRegistry) is not Object, throw a TypeError exception. 3. If finalizationRegistry does not have a [[Cells]] internal slot, throw a TypeError exception. 4. If callback is not undefined and IsCallable(callback) is false, throw a TypeError exception. 5. Perform ? CleanupFinalizationRegistry(finalizationRegistry, callback). 6. Return undefined. ---*/ let holdingsList = []; function cb(holding) { holdingsList.push(holding); }; let finalizationRegistry = new FinalizationRegistry(function() {}); let referenced = {}; function emptyCells() { let target = {}; finalizationRegistry.register(target, 'target!'); finalizationRegistry.register(referenced, 'referenced'); let prom = maybeGarbageCollectAndCleanupAsync(target); target = null; return prom; } promise_test(() => { return (async () => { assert_implements( typeof FinalizationRegistry.prototype.cleanupSome === 'function', 'FinalizationRegistry.prototype.cleanupSome is not implemented.' ); await emptyCells(); finalizationRegistry.cleanupSome(cb); assert_equals(holdingsList.length, 1); assert_equals(holdingsList[0], 'target!'); assert_equals(typeof referenced, 'object', 'referenced preserved'); })().catch(resolveGarbageCollection); }, 'cleanupCallback has only one optional chance to be called for a GC that cleans up a registered target.');