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// Copyright 2019 Google, Inc. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: prod-OptionalExpression
description: >
optional chain on member expression in async context
info: |
Left-Hand-Side Expressions
OptionalExpression
MemberExpression [PrimaryExpression identifier] OptionalChain
features: [optional-chaining]
flags: [async]
---*/
const a = undefined;
const c = {d: Promise.resolve(11)};
async function checkAssertions() {
assert.sameValue(await a?.b, undefined);
assert.sameValue(await c?.d, 11);
Promise.prototype.x = 42;
var res = await Promise.resolve(undefined)?.x;
assert.sameValue(res, 42, 'await unwraps the evaluation of the whole optional chaining expression #1');
Promise.prototype.y = 43;
var res = await Promise.reject(undefined)?.y;
assert.sameValue(res, 43, 'await unwraps the evaluation of the whole optional chaining expression #2');
c.e = Promise.resolve(39);
assert.sameValue(await c?.e, 39, 'await unwraps the promise given after the evaluation of the OCE');
}
checkAssertions().then($DONE, $DONE);
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