async-func-decl-dstr-obj-prop-elem-init-evaluation.js (1736B)
1 // |reftest| async 2 // This file was procedurally generated from the following sources: 3 // - src/dstr-assignment-for-await/obj-prop-elem-init-evaluation.case 4 // - src/dstr-assignment-for-await/default/async-func-decl.template 5 /*--- 6 description: The Initializer should only be evaluated if v is undefined. (for-await-of statement in an async function declaration) 7 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation 8 features: [destructuring-binding, async-iteration] 9 flags: [generated, async] 10 info: | 11 IterationStatement : 12 for await ( LeftHandSideExpression of AssignmentExpression ) Statement 13 14 1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« », 15 AssignmentExpression, iterate). 16 2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement, 17 keyResult, assignment, labelSet). 18 19 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation 20 21 [...] 22 5. If destructuring is true and if lhsKind is assignment, then 23 a. Assert: lhs is a LeftHandSideExpression. 24 b. Let assignmentPattern be the parse of the source text corresponding to 25 lhs using AssignmentPattern as the goal symbol. 26 [...] 27 ---*/ 28 let flag1 = false; 29 let flag2 = false; 30 let x, y; 31 32 let iterCount = 0; 33 async function fn() { 34 for await ({ x: x = flag1 = true, y: y = flag2 = true } of [{ y: 1 }]) { 35 assert.sameValue(x, true, 'value of `x`'); 36 assert.sameValue(flag1, true, 'value of `flag1`'); 37 assert.sameValue(y, 1, 'value of `y`'); 38 assert.sameValue(flag2, false, 'value of `flag2`'); 39 iterCount += 1; 40 } 41 } 42 43 let promise = fn(); 44 45 promise 46 .then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE) 47 .then($DONE, $DONE);