Home | History | Annotate | Download | only in es6 
      1 // Copyright 2014 the V8 project authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 var arrayIteratorPrototype = [].entries().__proto__;
      6 var iteratorPrototype = arrayIteratorPrototype.__proto__;
      7 
      8 assertSame(Object.prototype, Object.getPrototypeOf(iteratorPrototype));
      9 assertTrue(Object.isExtensible(iteratorPrototype));
     10 assertSame(0, Object.getOwnPropertyNames(iteratorPrototype).length);
     11 assertSame(1, Object.getOwnPropertySymbols(iteratorPrototype).length);
     12 assertSame(Symbol.iterator,
     13              Object.getOwnPropertySymbols(iteratorPrototype)[0]);
     14 
     15 var descr = Object.getOwnPropertyDescriptor(iteratorPrototype, Symbol.iterator);
     16 assertTrue(descr.configurable);
     17 assertFalse(descr.enumerable);
     18 assertTrue(descr.writable);
     19 
     20 var iteratorFunction = descr.value;
     21 assertSame('function', typeof iteratorFunction);
     22 assertSame(0, iteratorFunction.length);
     23 assertSame('[Symbol.iterator]', iteratorFunction.name);
     24 
     25 var obj = {};
     26 assertSame(obj, iteratorFunction.call(obj));
     27 assertSame(iteratorPrototype, iteratorPrototype[Symbol.iterator]());
     28 
     29 var mapIteratorPrototype = new Map().entries().__proto__;
     30 var setIteratorPrototype = new Set().values().__proto__;
     31 var stringIteratorPrototype = 'abc'[Symbol.iterator]().__proto__;
     32 assertSame(iteratorPrototype, mapIteratorPrototype.__proto__);
     33 assertSame(iteratorPrototype, setIteratorPrototype.__proto__);
     34 assertSame(iteratorPrototype, stringIteratorPrototype.__proto__);
     35 
     36 var typedArrays = [
     37   Float32Array,
     38   Float64Array,
     39   Int16Array,
     40   Int32Array,
     41   Int8Array,
     42   Uint16Array,
     43   Uint32Array,
     44   Uint8Array,
     45   Uint8ClampedArray,
     46 ];
     47 
     48 for (var constructor of typedArrays) {
     49   var array = new constructor();
     50   var iterator = array[Symbol.iterator]();
     51   assertSame(iteratorPrototype, iterator.__proto__.__proto__);
     52 }
     53 
     54 function* gen() {}
     55 assertSame(iteratorPrototype, gen.prototype.__proto__.__proto__);
     56 var g = gen();
     57 assertSame(gen.prototype, g.__proto__);
     58 assertSame(iteratorPrototype, g.__proto__.__proto__.__proto__);
     59