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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 call expression
info: |
Left-Hand-Side Expressions
OptionalExpression:
CallExpression OptionalChain
features: [optional-chaining]
---*/
// CallExpression CoverCallExpressionAndAsyncArrowHead
function fn () {
return {a: 33};
};
const obj = {
fn () {
return 44;
}
}
assert.sameValue(33, fn()?.a);
assert.sameValue(undefined, fn()?.b);
assert.sameValue(44, obj?.fn());
// CallExpression SuperCall
class A {}
class B extends A {
constructor () {
assert.sameValue(undefined, super()?.a);
}
}
new B();
// CallExpression Arguments
function fn2 () {
return () => {
return {a: 66};
};
}
function fn3 () {
return () => {
return null;
};
}
assert.sameValue(66, fn2()()?.a);
assert.sameValue(undefined, fn3()()?.a);
// CallExpression [Expression]
function fn4 () {
return [{a: 77}];
}
function fn5 () {
return [];
}
assert.sameValue(77, fn4()[0]?.a);
assert.sameValue(undefined, fn5()[0]?.a);
// CallExpression .IdentifierName
function fn6 () {
return {
a: {
b: 88
}
};
}
assert.sameValue(88, fn6().a?.b);
assert.sameValue(undefined, fn6().b?.c);
// CallExpression TemplateLiteral
function fn7 () {
return () => {};
}
assert.sameValue(undefined, fn7()`hello`?.a);
reportCompare(0, 0);