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diff --git a/js/src/tests/test262/built-ins/AsyncFromSyncIteratorPrototype/next/iterator-result-unwrap-promise.js b/js/src/tests/test262/built-ins/AsyncFromSyncIteratorPrototype/next/iterator-result-unwrap-promise.js
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+// |reftest| async
+// Copyright (C) 2018 Valerie Young. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-%asyncfromsynciteratorprototype%.next
+description: next() will unwrap a Promise value return by the sync iterator
+info: |
+  %AsyncFromSyncIteratorPrototype%.next ( value )
+  ...
+  2. Let promiseCapability be ! NewPromiseCapability(%Promise%).
+  ...
+  5. Let nextResult be IteratorNext(syncIteratorRecord, value).
+  6. IfAbruptRejectPromise(nextResult, promiseCapability).
+  7. Let nextDone be IteratorComplete(nextResult).
+  8. If AbruptRejectPromise(nextDone, promiseCapability).
+  9. Let nextValue be IteratorValue(nextResult).
+  10. IfAbruptRejectPromise(nextValue, promiseCapability).
+  ...
+  14. Let steps be the algorithm steps defined in Async-from-Sync Iterator Value Unwrap Functions.
+
+  Async-from-Sync Iterator Value Unwrap Functions
+  An async-from-sync iterator value unwrap function is an anonymous built-in
+  function that is used by methods of %AsyncFromSyncIteratorPrototype% when
+  processing the value field of an IteratorResult object, in order to wait for
+  its value if it is a promise and re-package the result in a new "unwrapped"
+  IteratorResult object. Each async iterator value unwrap function has a
+  [[Done]] internal slot.
+
+flags: [async]
+features: [async-iteration]
+---*/
+
+function* g() {
+  yield Promise.resolve(1);
+}
+
+async function* asyncg() {
+  yield* g();
+}
+
+asyncg().next().then(function (result) {
+  assert.sameValue(result.value, 1, "result.value should be unwrapped promise, got: " + result.value)
+}).then($DONE, $DONE);