1 files changed, 31 insertions, 0 deletions
diff --git a/js/src/tests/non262/AsyncIterator/prototype/lazy-methods-throw-eagerly-on-non-iterator.js b/js/src/tests/non262/AsyncIterator/prototype/lazy-methods-throw-eagerly-on-non-iterator.js
new file mode 100644
index 0000000000..1a61f5001a
--- /dev/null
+++ b/js/src/tests/non262/AsyncIterator/prototype/lazy-methods-throw-eagerly-on-non-iterator.js
@@ -0,0 +1,31 @@
+// |reftest| skip-if(!this.hasOwnProperty('AsyncIterator'))
+
+//
+//
+/*---
+esid: pending
+description: Lazy %AsyncIterator.prototype% methods throw eagerly when called on non-iterators.
+info: >
+  AsyncIterator Helpers proposal 1.1.1
+features: [iterator-helpers]
+---*/
+
+async function* gen(x) { yield x; }
+
+const methods = [
+  iter => AsyncIterator.prototype.map.bind(iter, x => x),
+  iter => AsyncIterator.prototype.filter.bind(iter, x => x),
+  iter => AsyncIterator.prototype.take.bind(iter, 1),
+  iter => AsyncIterator.prototype.drop.bind(iter, 0),
+  iter => AsyncIterator.prototype.asIndexedPairs.bind(iter),
+  iter => AsyncIterator.prototype.flatMap.bind(iter, gen),
+];
+
+for (const method of methods) {
+  for (const value of [undefined, null, 0, false, '', Symbol(''), {}, []]) {
+    assertThrowsInstanceOf(method(value), TypeError);
+  }
+}
+
+if (typeof reportCompare == 'function')
+  reportCompare(0, 0);