1 files changed, 108 insertions, 0 deletions
diff --git a/js/src/builtin/WeakSet.js b/js/src/builtin/WeakSet.js
new file mode 100644
index 000000000..eb7c2378f
--- /dev/null
+++ b/js/src/builtin/WeakSet.js
@@ -0,0 +1,108 @@
+/* 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);
+
+    // Step 6.c.
+    var iterFn = iterable[std_iterator];
+    if (!IsCallable(iterFn))
+        ThrowTypeError(JSMSG_NOT_ITERABLE, DecompileArg(0, iterable));
+
+    var iter = callContentFunction(iterFn, iterable);
+    if (!IsObject(iter))
+        ThrowTypeError(JSMSG_NOT_NONNULL_OBJECT, typeof iter);
+
+    // Step 7 (not applicable).
+
+    // Step 8.
+    while (true) {
+        // Step 8.a.
+        var next = callContentFunction(iter.next, iter);
+        if (!IsObject(next))
+            ThrowTypeError(JSMSG_NOT_NONNULL_OBJECT, typeof next);
+
+        // Step 8.b.
+        if (next.done)
+            return;
+
+        // Step 8.c.
+        var nextValue = next.value;
+
+        // Steps 8.d-e.
+        callContentFunction(adder, set, nextValue);
+    }
+}
+
+// 23.4.3.1
+function WeakSet_add(value) {
+    // Steps 1-3.
+    var S = this;
+    if (!IsObject(S) || !IsWeakSet(S))
+        return callFunction(CallWeakSetMethodIfWrapped, this, value, "WeakSet_add");
+
+    // Step 4.,6.
+    let entries = UnsafeGetReservedSlot(this, WEAKSET_MAP_SLOT);
+    if (!entries)
+        ThrowTypeError(JSMSG_INCOMPATIBLE_PROTO, "WeakSet", "add", typeof S);
+
+    // Step 5.
+    if (!IsObject(value))
+        ThrowTypeError(JSMSG_NOT_NONNULL_OBJECT, DecompileArg(0, value));
+
+    // Steps 7-8.
+    callFunction(std_WeakMap_set, entries, value, true);
+
+    // Step 8.
+    return S;
+}
+
+// 23.4.3.3
+function WeakSet_delete(value) {
+    // Steps 1-3.
+    var S = this;
+    if (!IsObject(S) || !IsWeakSet(S))
+        return callFunction(CallWeakSetMethodIfWrapped, this, value, "WeakSet_delete");
+
+    // Step 4.,6.
+    let entries = UnsafeGetReservedSlot(this, WEAKSET_MAP_SLOT);
+    if (!entries)
+        ThrowTypeError(JSMSG_INCOMPATIBLE_PROTO, "WeakSet", "delete", typeof S);
+
+    // Step 5.
+    if (!IsObject(value))
+        return false;
+
+    // Steps 7-8.
+    return callFunction(std_WeakMap_delete, entries, value);
+}
+
+// 23.4.3.4
+function WeakSet_has(value) {
+    // Steps 1-3.
+    var S = this;
+    if (!IsObject(S) || !IsWeakSet(S))
+        return callFunction(CallWeakSetMethodIfWrapped, this, value, "WeakSet_has");
+
+    // Step 4-5.
+    let entries = UnsafeGetReservedSlot(this, WEAKSET_MAP_SLOT);
+    if (!entries)
+        ThrowTypeError(JSMSG_INCOMPATIBLE_PROTO, "WeakSet", "has", typeof S);
+
+    // Step 6.
+    if (!IsObject(value))
+        return false;
+
+    // Steps 7-8.
+    return callFunction(std_WeakMap_has, entries, value);
+}