// Copyright (C) 2018 Leo Balter. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- esid: sec-array.prototype.flatMap description: > Does not flatten array-like objects nested into the main array info: | FlattenIntoArray(target, source, sourceLen, start, depth [ , mapperFunction, thisArg ]) 1. Let targetIndex be start. 2. Let sourceIndex be 0. 3. Repeat, while sourceIndex < sourceLen a. Let P be ! ToString(sourceIndex). b. Let exists be ? HasProperty(source, P). c. If exists is true, then i. Let element be ? Get(source, P). ii. If mapperFunction is present, then 1. Assert: thisArg is present. 2. Set element to ? Call(mapperFunction, thisArg , « element, sourceIndex, source »). iii. Let shouldFlatten be false. iv. If depth > 0, then 1. Set shouldFlatten to ? IsArray(element). v. If shouldFlatten is true, then 1. Let elementLen be ? ToLength(? Get(element, "length")). 2. Set targetIndex to ? FlattenIntoArray(target, element, elementLen, targetIndex, depth - 1). vi. Else, 1. If targetIndex ≥ 253-1, throw a TypeError exception. 2. Perform ? CreateDataPropertyOrThrow(target, ! ToString(targetIndex), element). 3. Increase targetIndex by 1. includes: [compareArray.js] features: [Array.prototype.flatMap, Int32Array] ---*/ function fn(e) { return e; } var obj1 = { length: 1, 0: 'a', toString() { return 'obj1'; } }; var obj2 = new Int32Array(2); var obj3 = { get length() { throw "should not even consider the length property" }, toString() { return 'obj3'; } }; var arr = [obj1, obj2, obj3]; var actual = arr.flatMap(fn); assert.compareArray(actual, arr, 'The value of actual is expected to equal the value of arr'); assert.notSameValue(actual, arr, 'The value of actual is expected to not equal the value of `arr`'); var arrLike = { length: 4, 0: obj1, 1: obj2, 2: obj3, get 3() { return arrLike }, toString() { return 'obj4'; } }; actual = [].flatMap.call(arrLike, fn); assert.compareArray(actual, [obj1, obj2, obj3, arrLike], 'The value of actual is expected to be [obj1, obj2, obj3, arrLike]'); assert.notSameValue(actual, arrLike, 'The value of actual is expected to not equal the value of `arrLike`'); assert.sameValue( Object.getPrototypeOf(actual), Array.prototype, 'Object.getPrototypeOf([].flatMap.call(arrLike, fn)") returns Array.prototype' ); reportCompare(0, 0);