Strict mode Passingnon-Strict mode Passing
Features:
- ∅
// Copyright (c) 2012 Ecma International. All rights reserved. // This code is governed by the BSD license found in the LICENSE file. /*--- esid: sec-array.prototype.indexof description: > Array.prototype.indexOf - value of 'fromIndex' is an Object, which has an own toString method ---*/ // objects inherit the default valueOf() method from Object // that simply returns itself. Since the default valueOf() method // does not return a primitive value, ES next tries to convert the object // to a number by calling its toString() method and converting the // resulting string to a number. var fromIndex = { toString: function() { return '1'; } }; assert.sameValue([0, true].indexOf(true, fromIndex), 1, '[0, true].indexOf(true, fromIndex)');