1 files changed, 22 insertions, 0 deletions
diff --git a/js/src/builtin/WeakSet.js b/js/src/builtin/WeakSet.js
new file mode 100644
index 0000000000..adf067863a
--- /dev/null
+++ b/js/src/builtin/WeakSet.js
@@ -0,0 +1,22 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// ES2017 draft rev 0e10c9f29fca1385980c08a7d5e7bb3eb775e2e4
+// 23.4.1.1 WeakSet, steps 6-8
+function WeakSetConstructorInit(iterable) {
+  var set = this;
+
+  // Step 6.a.
+  var adder = set.add;
+
+  // Step 6.b.
+  if (!IsCallable(adder)) {
+    ThrowTypeError(JSMSG_NOT_FUNCTION, typeof adder);
+  }
+
+  // Steps 6.c-8.
+  for (var nextValue of allowContentIter(iterable)) {
+    callContentFunction(adder, set, nextValue);
+  }
+}