async-gen-decl-dstr-array-elem-iter-nrml-close-null.js (2401B)
1 // |reftest| async 2 // This file was procedurally generated from the following sources: 3 // - src/dstr-assignment-for-await/array-elem-iter-nrml-close-null.case 4 // - src/dstr-assignment-for-await/async-generator/async-gen-decl.template 5 /*--- 6 description: IteratorClose throws a TypeError when `return` returns a non-Object value (for-await-of statement in an async generator declaration) 7 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation 8 features: [Symbol.iterator, 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 ArrayAssignmentPattern : [ AssignmentElementList ] 29 30 [...] 31 4. If iteratorRecord.[[Done]] is false, return ? IteratorClose(iterator, result). 32 5. Return result. 33 34 7.4.6 IteratorClose( iterator, completion ) 35 36 [...] 37 5. Let innerResult be Call(return, iterator, « »). 38 6. If completion.[[Type]] is throw, return Completion(completion). 39 7. If innerResult.[[Type]] is throw, return Completion(innerResult). 40 8. If Type(innerResult.[[Value]]) is not Object, throw a TypeError exception. 41 42 ---*/ 43 let _; 44 let nextCount = 0; 45 let iterator = { 46 next() { 47 nextCount += 1; 48 // Set an upper-bound to limit unnecessary iteration in non-conformant 49 // implementations 50 return { done: nextCount > 10 }; 51 }, 52 return() { 53 return null; 54 } 55 }; 56 let iterable = { 57 [Symbol.iterator]() { 58 return iterator; 59 } 60 }; 61 62 let iterCount = 0; 63 async function * fn() { 64 for await ([ _ ] of [iterable]) { 65 66 iterCount += 1; 67 } 68 } 69 70 let iter = fn(); 71 72 iter.next().then(() => $DONE('Promise incorrectly fulfilled.'), ({ constructor }) => { 73 assert.sameValue(nextCount, 1); 74 assert.sameValue(constructor, TypeError); 75 }).then($DONE, $DONE);