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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
description: >
Creation of new lexical environment for each evaluation of the statement
body
info: |
IterationStatement : for ( ForDeclaration of AssignmentExpression ) Statement
[...]
2. Return ? ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult,
lexicalBinding, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
5. Repeat
[...]
i. Let result be the result of evaluating stmt.
j. Set the running execution context's LexicalEnvironment to oldEnv.
k. If LoopContinues(result, labelSet) is false, return ?
IteratorClose(iterator, UpdateEmpty(result, V)).
l. If result.[[Value]] is not empty, let V be result.[[Value]].
features: [let]
---*/
let x = 'outside';
var probeFirst, probeSecond;
for (let x in { a: 0, b: 0 })
if (!probeFirst)
probeFirst = function() { return x; };
else
probeSecond = function() { return x; };
// 13.7.5.15 EnumerateObjectProperties
//
// > [...] The mechanics and order of enumerating the properties is not
// > specified [...]
assert.notSameValue(probeFirst(), probeSecond());
assert(
probeFirst() === 'a' || probeFirst() === 'b',
'First binding is either "a" or "b"'
);
assert(
probeSecond() === 'a' || probeSecond() === 'b',
'Second binding is either "a" or "b"'
);
reportCompare(0, 0);