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// Copyright (c) 2012 Ecma International. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
es5id: 15.4.4.15-4-8
description: >
Array.prototype.lastIndexOf returns -1 if 'length' is 0 (length is
an empty array)
includes: [runTestCase.js]
---*/
function testcase() {
// objects inherit the default valueOf method of the Object object;
// that simply returns the 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.
//
// The toString( ) method on Array converts the array elements to strings,
// then returns the result of concatenating these strings, with commas in
// between. An array with no elements converts to the empty string, which
// converts to the number 0. If an array has a single element that is a
// number n, the array converts to a string representation of n, which is
// then converted back to n itself. If an array contains more than one element,
// or if its one element is not a number, the array converts to NaN.
var i = Array.prototype.lastIndexOf.call({length: [ ]}, 1);
if (i === -1) {
return true;
}
}
runTestCase(testcase);
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