1 files changed, 41 insertions, 0 deletions
diff --git a/deps/v8/test/mjsunit/harmony/weakrefs/unregister-inside-cleanup1.js b/deps/v8/test/mjsunit/harmony/weakrefs/unregister-inside-cleanup1.js
new file mode 100644
index 0000000000..aa9eab20ff
--- /dev/null
+++ b/deps/v8/test/mjsunit/harmony/weakrefs/unregister-inside-cleanup1.js
@@ -0,0 +1,41 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --harmony-weak-refs --expose-gc --noincremental-marking
+
+let cleanup_call_count = 0;
+let cleanup_holdings_count = 0;
+let cleanup = function(iter) {
+  // Unregister before we've iterated through the holdings.
+  fg.unregister(key);
+
+  for (wc of iter) {
+    ++cleanup_holdings_count;
+  }
+  ++cleanup_call_count;
+}
+
+let fg = new FinalizationGroup(cleanup);
+let key = {"k": "the key"};
+// Create an object and register it in the FinalizationGroup. The object needs
+// to be inside a closure so that we can reliably kill them!
+
+(function() {
+  let object = {};
+  fg.register(object, "holdings", key);
+
+  // object goes out of scope.
+})();
+
+// This GC will discover unretained targets and schedule cleanup.
+gc();
+assertEquals(0, cleanup_call_count);
+
+// Assert that the cleanup function was called, but didn't iterate any holdings.
+let timeout_func = function() {
+  assertEquals(1, cleanup_call_count);
+  assertEquals(0, cleanup_holdings_count);
+}
+
+setTimeout(timeout_func, 0);