lepu-test-platform-web/node_modules/es-abstract/helpers/DefineOwnProperty.js

46 lines
1.2 KiB
JavaScript

'use strict';
var GetIntrinsic = require('../GetIntrinsic');
var $defineProperty = GetIntrinsic('%Object.defineProperty%', true);
if ($defineProperty) {
try {
$defineProperty({}, 'a', { value: 1 });
} catch (e) {
// IE 8 has a broken defineProperty
$defineProperty = null;
}
}
var callBound = require('../helpers/callBound');
var $isEnumerable = callBound('Object.prototype.propertyIsEnumerable');
// eslint-disable-next-line max-params
module.exports = function DefineOwnProperty(IsDataDescriptor, SameValue, FromPropertyDescriptor, O, P, desc) {
if (!$defineProperty) {
if (!IsDataDescriptor(desc)) {
// ES3 does not support getters/setters
return false;
}
if (!desc['[[Configurable]]'] || !desc['[[Writable]]']) {
return false;
}
// fallback for ES3
if (P in O && $isEnumerable(O, P) !== !!desc['[[Enumerable]]']) {
// a non-enumerable existing property
return false;
}
// property does not exist at all, or exists but is enumerable
var V = desc['[[Value]]'];
// eslint-disable-next-line no-param-reassign
O[P] = V; // will use [[Define]]
return SameValue(O[P], V);
}
$defineProperty(O, P, FromPropertyDescriptor(desc));
return true;
};