mirror of https://github.com/tc39/test262.git
51 lines
1.7 KiB
JavaScript
51 lines
1.7 KiB
JavaScript
// This file was procedurally generated from the following sources:
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// - src/dstr-assignment-for-await/array-elem-init-yield-expr.case
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// - src/dstr-assignment-for-await/async-generator/async-gen-decl.template
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/*---
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description: When a `yield` token appears within the Initializer of an AssignmentElement within a generator function body, it behaves as a YieldExpression. (for-await-of statement in an async generator declaration)
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esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
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features: [generators, destructuring-binding, async-iteration]
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flags: [generated, async]
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info: |
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IterationStatement :
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for await ( LeftHandSideExpression of AssignmentExpression ) Statement
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1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
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AssignmentExpression, iterate).
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2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
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keyResult, assignment, labelSet).
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13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
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[...]
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5. If destructuring is true and if lhsKind is assignment, then
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a. Assert: lhs is a LeftHandSideExpression.
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b. Let assignmentPattern be the parse of the source text corresponding to
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lhs using AssignmentPattern as the goal symbol.
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[...]
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---*/
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let value = [];
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let x;
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let iterCount = 0;
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async function * fn() {
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for await ([ x = yield ] of [[]]) {
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iterCount += 1;
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}
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}
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let iter = fn();
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iter.next().then(result => {
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assert.sameValue(result.value, undefined);
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assert.sameValue(result.done, false);
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assert.sameValue(x, undefined);
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iter.next(4).then(result => {
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assert.sameValue(result.value, undefined);
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assert.sameValue(result.done, true);
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assert.sameValue(x, 4);
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}).then($DONE, $DONE);
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}, $DONE).catch($DONE);
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