1 files changed, 21 insertions, 0 deletions
diff --git a/js/src/tests/non262/WeakMap/symbols.js b/js/src/tests/non262/WeakMap/symbols.js
new file mode 100644
index 0000000000..92d8412f47
--- /dev/null
+++ b/js/src/tests/non262/WeakMap/symbols.js
@@ -0,0 +1,21 @@
+// |reftest| shell-option(--enable-symbols-as-weakmap-keys) skip-if(!xulRuntime.shell||!(this.hasOwnProperty('getBuildConfiguration')&&!getBuildConfiguration('release_or_beta'))) -- requires shell-options
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/ */
+
+var m = new WeakMap;
+var sym = Symbol();
+m.set(sym, 0);
+assertEq(m.get(sym), 0);
+
+// sym1 will be registered in global Symbol registry hence cannot be used as a
+// key in WeakMap.
+var sym1 = Symbol.for("testKey");
+assertThrowsInstanceOf(() => m.set(sym1, 1), TypeError);
+
+// Well-known symbols can be used as weakmap keys.
+var sym2 = Symbol.hasInstance;
+m.set(sym2, 2);
+assertEq(m.get(sym2), 2);
+
+if (typeof reportCompare === "function")
+  reportCompare(0, 0);