iterator-closed-for-string-entry.js (1552B)
1 // Copyright (C) 2018 Kevin Gibbons. All rights reserved. 2 // This code is governed by the BSD license found in the LICENSE file. 3 4 /*--- 5 esid: sec-object.fromentries 6 description: Closes iterators when they return entries which are strings. 7 info: | 8 Object.fromEntries ( iterable ) 9 10 ... 11 4. Let stepsDefine be the algorithm steps defined in CreateDataPropertyOnObject Functions. 12 5. Let adder be CreateBuiltinFunction(stepsDefine, « »). 13 6. Return ? AddEntriesFromIterable(obj, iterable, adder). 14 15 AddEntriesFromIterable ( target, iterable, adder ) 16 17 ... 18 4. Repeat, 19 ... 20 d. If Type(nextItem) is not Object, then 21 i. Let error be ThrowCompletion(a newly created TypeError object). 22 ii. Return ? IteratorClose(iteratorRecord, error). 23 24 features: [Symbol.iterator, Object.fromEntries] 25 ---*/ 26 27 var returned = false; 28 var iterable = { 29 [Symbol.iterator]: function() { 30 var advanced = false; 31 return { 32 next: function() { 33 if (advanced) { 34 throw new Test262Error('should only advance once'); 35 } 36 advanced = true; 37 return { 38 done: false, 39 value: 'ab', 40 }; 41 }, 42 return: function() { 43 if (returned) { 44 throw new Test262Error('should only return once'); 45 } 46 returned = true; 47 }, 48 }; 49 }, 50 }; 51 52 assert.sameValue(typeof Object.fromEntries, 'function'); 53 assert.throws(TypeError, function() { 54 Object.fromEntries(iterable); 55 }); 56 57 assert(returned, 'iterator should be closed when entry is a string'); 58 59 reportCompare(0, 0);