async-gen-decl-dstr-array-elision-iter-nrml-close.js (2518B)
1 // |reftest| async 2 // This file was procedurally generated from the following sources: 3 // - src/dstr-assignment-for-await/array-elision-iter-nrml-close.case 4 // - src/dstr-assignment-for-await/async-generator/async-gen-decl.template 5 /*--- 6 description: IteratorClose is called when assignment evaluation has not exhausted the iterator (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 : [ Elision ] 29 30 1. Let iterator be ? GetIterator(value). 31 32 [...] 33 34 4. If iteratorRecord.[[Done]] is false, return ? IteratorClose(iterator, result).. 35 [...] 36 37 7.4.6 IteratorClose ( iterator, completion ) 38 39 [...] 40 5. Let innerResult be Call(return, iterator, « »). 41 [...] 42 43 ---*/ 44 let nextCount = 0; 45 let returnCount = 0; 46 let thisValue = null; 47 let args = null; 48 let iterator = { 49 next() { 50 nextCount += 1; 51 // Set an upper-bound to limit unnecessary iteration in non-conformant 52 // implementations 53 return { done: nextCount > 10 }; 54 }, 55 return() { 56 returnCount += 1; 57 thisValue = this; 58 args = arguments; 59 return {}; 60 } 61 }; 62 let iterable = { 63 [Symbol.iterator]() { 64 return iterator; 65 } 66 }; 67 68 69 let iterCount = 0; 70 async function * fn() { 71 for await ([ , ] of [iterable]) { 72 assert.sameValue(nextCount, 1); 73 assert.sameValue(returnCount, 1); 74 assert.sameValue(thisValue, iterator, 'correct `this` value'); 75 assert(!!args, 'arguments object provided'); 76 assert.sameValue(args.length, 0, 'zero arguments specified'); 77 78 79 iterCount += 1; 80 } 81 } 82 83 let iter = fn(); 84 85 iter.next() 86 .then(() => assert.sameValue(iterCount, 1, 'iteration occurred as expected'), $DONE) 87 .then($DONE, $DONE);