array-elem-trlg-iter-rest-thrw-close.js (2243B)
1 // This file was procedurally generated from the following sources: 2 // - src/dstr-assignment/array-elem-trlg-iter-rest-thrw-close.case 3 // - src/dstr-assignment/error/assignment-expr.template 4 /*--- 5 description: IteratorClose is called when AssignmentRestEvaluation produces a "throw" completion due to reference evaluation (AssignmentExpression) 6 esid: sec-variable-statement-runtime-semantics-evaluation 7 features: [Symbol.iterator, destructuring-binding] 8 flags: [generated] 9 info: | 10 VariableDeclaration : BindingPattern Initializer 11 12 1. Let rhs be the result of evaluating Initializer. 13 2. Let rval be GetValue(rhs). 14 3. ReturnIfAbrupt(rval). 15 4. Return the result of performing BindingInitialization for 16 BindingPattern passing rval and undefined as arguments. 17 18 ArrayAssignmentPattern : 19 [ AssignmentElementList , Elisionopt AssignmentRestElementopt ] 20 21 [...] 22 7. If AssignmentRestElement is present, then 23 a. Let status be the result of performing 24 IteratorDestructuringAssignmentEvaluation of AssignmentRestElement 25 with iteratorRecord as the argument. 26 8. If iteratorRecord.[[done]] is false, return IteratorClose(iterator, 27 status). 28 9. Return Completion(status). 29 30 7.4.6 IteratorClose( iterator, completion ) 31 32 [...] 33 6. Let innerResult be Call(return, iterator, « »). 34 [...] 35 36 ---*/ 37 var nextCount = 0; 38 var returnCount = 0; 39 var thisValue = null; 40 var args = null; 41 var iterable = {}; 42 var x; 43 var iterator = { 44 next: function() { 45 nextCount += 1; 46 // Set an upper-bound to limit unnecessary iteration in non-conformant 47 // implementations 48 return { done: nextCount > 10 }; 49 }, 50 return: function() { 51 returnCount += 1; 52 thisValue = this; 53 args = arguments; 54 } 55 }; 56 var thrower = function() { 57 throw new Test262Error(); 58 }; 59 iterable[Symbol.iterator] = function() { 60 return iterator; 61 }; 62 63 assert.throws(Test262Error, function() { 64 0, [ x , ...{}[thrower()] ] = iterable; 65 }); 66 67 assert.sameValue(nextCount, 1); 68 assert.sameValue(returnCount, 1); 69 assert.sameValue(thisValue, iterator, 'correct `this` value'); 70 assert(!!args, 'arguments object provided'); 71 assert.sameValue(args.length, 0, 'zero arguments specified'); 72 73 reportCompare(0, 0);