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3b3bd06819
Add tests that assert the management of the running execution context's LexicalEnvironment and VariableEnvironment components, as created by the following abstract operations: - NewDeclarativeEnvironment - NewObjectEnvironment - NewFunctionEnvironment Many tests require the use of non-strict direct eval, meaning they may not be run in strict mode. This does not effect coverage because the semantics in these cases are not observable from strict mode code. Some situations require the creation of a binding, but this binding has no relevance to the test itself. In these cases, use names consisting solely of the underscore character (`_`). Avoid the use of Block statements wherever possible, as these trigger the creation of additional environments which may interfere with the behavior under test.
39 lines
1.3 KiB
JavaScript
39 lines
1.3 KiB
JavaScript
// Copyright (C) 2016 the V8 project authors. All rights reserved.
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// This code is governed by the BSD license found in the LICENSE file.
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/*---
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esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
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description: >
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Creation of new lexical environment to serve as a temporal dead zone for
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the statement's AssignmentExpresson
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info: |
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IterationStatement : for ( ForDeclaration of AssignmentExpression ) Statement
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1. Let keyResult be the result of performing ?
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ForIn/OfHeadEvaluation(BoundNames of ForDeclaration,
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AssignmentExpression, iterate).
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[...]
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13.7.5.12 Runtime Semantics: ForIn/OfHeadEvaluation
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[...]
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2. If TDZnames is not an empty List, then
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a. Assert: TDZnames has no duplicate entries.
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b. Let TDZ be NewDeclarativeEnvironment(oldEnv).
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c. Let TDZEnvRec be TDZ's EnvironmentRecord.
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d. For each string name in TDZnames, do
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i. Perform ! TDZEnvRec.CreateMutableBinding(name, false).
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e. Set the running execution context's LexicalEnvironment to TDZ.
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3. Let exprRef be the result of evaluating expr.
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[...]
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features: [let]
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---*/
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let x = 'outside';
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var probeBefore = function() { return x; };
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var probeExpr;
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for (let x of (probeExpr = function() { typeof x; }, [])) ;
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assert.sameValue(probeBefore(), 'outside');
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assert.throws(ReferenceError, probeExpr);
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