1 files changed, 50 insertions, 0 deletions
diff --git a/js/src/tests/non262/AsyncIterator/prototype/lazy-methods-throw-next-not-object.js b/js/src/tests/non262/AsyncIterator/prototype/lazy-methods-throw-next-not-object.js
new file mode 100644
index 0000000000..bb38a67000
--- /dev/null
+++ b/js/src/tests/non262/AsyncIterator/prototype/lazy-methods-throw-next-not-object.js
@@ -0,0 +1,50 @@
+// |reftest| skip-if(!this.hasOwnProperty('AsyncIterator'))
+
+//
+//
+/*---
+esid: pending
+description: Lazy %AsyncIterator.prototype% methods throw if `next` call returns a non-object.
+info: >
+  Iterator Helpers proposal 2.1.6
+features: [iterator-helpers]
+---*/
+
+class TestAsyncIterator extends AsyncIterator {
+  async next(value) {
+    return value;
+  }
+
+  closed = false;
+  async return() {
+    this.closed = true;
+    return {done: true};
+  }
+}
+
+async function* gen(x) { yield x; }
+const methods = [
+  iter => iter.map(x => x),
+  iter => iter.filter(x => x),
+  iter => iter.take(1),
+  iter => iter.drop(0),
+  iter => iter.asIndexedPairs(),
+  iter => iter.flatMap(gen),
+];
+
+for (const method of methods) {
+  for (const value of [undefined, null, 0, false, '', Symbol('')]) {
+    const iterator = new TestAsyncIterator();
+    assertEq(iterator.closed, false);
+    method(iterator).next(value).then(
+      _ => assertEq(true, false, 'Expected reject'),
+      err => {
+        assertEq(err instanceof TypeError, true);
+        assertEq(iterator.closed, false);
+      },
+    );
+  }
+}
+
+if (typeof reportCompare == 'function')
+  reportCompare(0, 0);