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// Copyright (C) 2017 Mozilla Corporation. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-object-environment-records-hasbinding-n
description: >
@@unscopables should be looked up exactly once for inc/dec.
info: |
UpdateExpression : LeftHandSideExpression ++
1. Let lhs be the result of evaluating LeftHandSideExpression.
GetIdentifierReference ( lex, name, strict )
[...]
3. Let exists be ? envRec.HasBinding(name).
HasBinding ( N )
[...]
6. Let unscopables be ? Get(bindings, @@unscopables).
flags: [noStrict]
features: [Symbol.unscopables]
---*/
var unscopablesGetterCalled = 0;
var a, b, flag = true;
with (a = { x: 7 }) {
with (b = { x: 4, get [Symbol.unscopables]() {
unscopablesGetterCalled++;
return { x: flag=!flag };
} }) {
x++;
}
}
assert.sameValue(unscopablesGetterCalled, 1);
assert.sameValue(a.x, 7);
assert.sameValue(b.x, 5);
unscopablesGetterCalled = 0;
flag = true;
with (a = { x: 7 }) {
with (b = { x: 4, get [Symbol.unscopables]() {
unscopablesGetterCalled++;
return { x: flag=!flag };
} }) {
x--;
}
}
assert.sameValue(unscopablesGetterCalled, 1);
assert.sameValue(a.x, 7);
assert.sameValue(b.x, 3);
reportCompare(0, 0);