array-elision-iter-nrml-close.js (2284B)
1 // This file was procedurally generated from the following sources: 2 // - src/dstr-assignment/array-elision-iter-nrml-close.case 3 // - src/dstr-assignment/default/for-of.template 4 /*--- 5 description: IteratorClose is called when assignment evaluation has not exhausted the iterator (For..of statement) 6 esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation 7 features: [Symbol.iterator, destructuring-binding] 8 flags: [generated] 9 info: | 10 IterationStatement : 11 for ( LeftHandSideExpression of AssignmentExpression ) Statement 12 13 1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« », 14 AssignmentExpression, iterate). 15 2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement, 16 keyResult, assignment, labelSet). 17 18 13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation 19 20 [...] 21 4. If destructuring is true and if lhsKind is assignment, then 22 a. Assert: lhs is a LeftHandSideExpression. 23 b. Let assignmentPattern be the parse of the source text corresponding to 24 lhs using AssignmentPattern as the goal symbol. 25 [...] 26 27 ArrayAssignmentPattern : [ Elision ] 28 29 1. Let iterator be GetIterator(value). 30 [...] 31 5. If iteratorRecord.[[done]] is false, return IteratorClose(iterator, 32 result). 33 [...] 34 35 7.4.6 IteratorClose( iterator, completion ) 36 37 [...] 38 6. Let innerResult be Call(return, iterator, « »). 39 [...] 40 41 ---*/ 42 var nextCount = 0; 43 var returnCount = 0; 44 var thisValue = null; 45 var args = null; 46 var iterable = {}; 47 var iterator = { 48 next: function() { 49 nextCount += 1; 50 // Set an upper-bound to limit unnecessary iteration in non-conformant 51 // implementations 52 return { done: nextCount > 10 }; 53 }, 54 return: function() { 55 returnCount += 1; 56 thisValue = this; 57 args = arguments; 58 return {}; 59 } 60 }; 61 iterable[Symbol.iterator] = function() { 62 return iterator; 63 }; 64 65 var counter = 0; 66 67 for ([ , ] of [iterable]) { 68 assert.sameValue(nextCount, 1); 69 assert.sameValue(returnCount, 1); 70 assert.sameValue(thisValue, iterator, 'correct `this` value'); 71 assert(!!args, 'arguments object provided'); 72 assert.sameValue(args.length, 0, 'zero arguments specified'); 73 counter += 1; 74 } 75 76 assert.sameValue(counter, 1); 77 78 reportCompare(0, 0);