array-set-length.js•1.01 kB
'use strict';
var DESCRIPTORS = require('../internals/descriptors');
var isArray = require('../internals/is-array');
var $TypeError = TypeError;
// eslint-disable-next-line es/no-object-getownpropertydescriptor -- safe
var getOwnPropertyDescriptor = Object.getOwnPropertyDescriptor;
// Safari < 13 does not throw an error in this case
var SILENT_ON_NON_WRITABLE_LENGTH_SET = DESCRIPTORS && !function () {
// makes no sense without proper strict mode support
if (this !== undefined) return true;
try {
// eslint-disable-next-line es/no-object-defineproperty -- safe
Object.defineProperty([], 'length', { writable: false }).length = 1;
} catch (error) {
return error instanceof TypeError;
}
}();
module.exports = SILENT_ON_NON_WRITABLE_LENGTH_SET ? function (O, length) {
if (isArray(O) && !getOwnPropertyDescriptor(O, 'length').writable) {
throw new $TypeError('Cannot set read only .length');
} return O.length = length;
} : function (O, length) {
return O.length = length;
};