array-elem-trlg-iter-elision-iter-nrml-close.js (2561B)
1 // This file was procedurally generated from the following sources: 2 // - src/dstr-assignment/array-elem-trlg-iter-elision-iter-nrml-close.case 3 // - src/dstr-assignment/default/for-of.template 4 /*--- 5 description: IteratorClose invoked when elision does not exhaust 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 : 28 [ AssignmentElementList , Elisionopt AssignmentRestElementopt ] 29 30 [...] 31 6. If Elision is present, then 32 a. Let status be the result of performing 33 IteratorDestructuringAssignmentEvaluation of Elision with 34 iteratorRecord as the argument. 35 b. If status is an abrupt completion, then 36 [...] 37 8. If iteratorRecord.[[done]] is false, return IteratorClose(iterator, 38 status). 39 40 7.4.6 IteratorClose( iterator, completion ) 41 42 [...] 43 6. Let innerResult be Call(return, iterator, « »). 44 [...] 45 46 ---*/ 47 var nextCount = 0; 48 var returnCount = 0; 49 var thisValue = null; 50 var args = null; 51 var iterable = {}; 52 var x; 53 var iterator = { 54 next: function() { 55 nextCount += 1; 56 57 // Set an upper-bound to limit unnecessary iteration in non-conformant 58 // implementations 59 return { done: nextCount > 10 }; 60 }, 61 return: function() { 62 returnCount += 1; 63 thisValue = this; 64 args = arguments; 65 return {}; 66 } 67 }; 68 iterable[Symbol.iterator] = function() { 69 return iterator; 70 }; 71 72 var counter = 0; 73 74 for ([ x , , ] of [iterable]) { 75 assert.sameValue(nextCount, 2); 76 assert.sameValue(returnCount, 1); 77 assert.sameValue(thisValue, iterator, 'correct `this` value'); 78 assert(!!args, 'arguments object provided'); 79 assert.sameValue(args.length, 0, 'zero arguments specified'); 80 counter += 1; 81 } 82 83 assert.sameValue(counter, 1); 84 85 reportCompare(0, 0);