1 files changed, 61 insertions, 0 deletions
diff --git a/js/src/tests/non262/Array/unscopables.js b/js/src/tests/non262/Array/unscopables.js
new file mode 100644
index 0000000000..9827245445
--- /dev/null
+++ b/js/src/tests/non262/Array/unscopables.js
@@ -0,0 +1,61 @@
+if (typeof getBuildConfiguration === "undefined") {
+  var getBuildConfiguration = SpecialPowers.Cu.getJSTestingFunctions().getBuildConfiguration;
+}
+
+var isNightly = !getBuildConfiguration().release_or_beta;
+
+let Array_unscopables = Array.prototype[Symbol.unscopables];
+
+let desc = Reflect.getOwnPropertyDescriptor(Array.prototype, Symbol.unscopables);
+assertDeepEq(desc, {
+    value: Array_unscopables,
+    writable: false,
+    enumerable: false,
+    configurable: true
+});
+
+assertEq(Reflect.getPrototypeOf(Array_unscopables), null);
+
+let desc2 = Object.getOwnPropertyDescriptor(Array_unscopables, "values");
+assertDeepEq(desc2, {
+    value: true,
+    writable: true,
+    enumerable: true,
+    configurable: true
+});
+
+let keys = Reflect.ownKeys(Array_unscopables);
+
+assertDeepEq(keys, [
+    ...(isNightly ? ["at"] : []),
+    ...[
+    "copyWithin",
+    "entries",
+    "fill",
+    "find",
+    "findIndex",
+    "flat",
+    "flatMap",
+    "includes",
+    "keys",
+    "values"
+]]);
+
+for (let key of keys)
+    assertEq(Array_unscopables[key], true);
+
+// Test that it actually works
+assertThrowsInstanceOf(() => {
+    with ([]) {
+        return entries;
+    }
+}, ReferenceError);
+
+{
+    let fill = 33;
+    with (Array.prototype) {
+        assertEq(fill, 33);
+    }
+}
+
+reportCompare(0, 0);