1 files changed, 49 insertions, 0 deletions
diff --git a/deps/v8/test/mjsunit/harmony/weakrefs/iterating-weak-cells.js b/deps/v8/test/mjsunit/harmony/weakrefs/iterating-weak-cells.js
new file mode 100644
index 0000000000..9fef051122
--- /dev/null
+++ b/deps/v8/test/mjsunit/harmony/weakrefs/iterating-weak-cells.js
@@ -0,0 +1,49 @@
+// 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_called = false;
+let cleanup = function(iter) {
+  assertFalse(cleanup_called);
+  let cells = [];
+  for (wc of iter) {
+    cells.push(wc);
+  }
+  assertEquals(cells.length, 2);
+  if (cells[0] == wc1) {
+    assertEquals(cells[0].holdings, 1);
+    assertEquals(cells[1], wc2);
+    assertEquals(cells[1].holdings, 2);
+  } else {
+    assertEquals(cells[0], wc2);
+    assertEquals(cells[0].holdings, 2);
+    assertEquals(cells[1], wc1);
+    assertEquals(cells[1].holdings, 1);
+  }
+  cleanup_called = true;
+}
+
+let wf = new WeakFactory(cleanup);
+let o1 = {};
+let o2 = {};
+let wc1 = wf.makeCell(o1, 1);
+let wc2 = wf.makeCell(o2, 2);
+
+gc();
+assertFalse(cleanup_called);
+
+// Drop the last references to o1 and o2.
+o1 = null;
+o2 = null;
+// GC will clear the WeakCells; the cleanup function will be called the next time
+// we enter the event loop.
+gc();
+assertFalse(cleanup_called);
+
+let timeout_func = function() {
+  assertTrue(cleanup_called);
+}
+
+setTimeout(timeout_func, 0);