index.js 817 Bytes
'use strict';

var GetIntrinsic = require('get-intrinsic');

var $defineProperty = GetIntrinsic('%Object.defineProperty%', true);

var hasPropertyDescriptors = function hasPropertyDescriptors() {
	if ($defineProperty) {
		try {
			$defineProperty({}, 'a', { value: 1 });
			return true;
		} catch (e) {
			// IE 8 has a broken defineProperty
			return false;
		}
	}
	return false;
};

hasPropertyDescriptors.hasArrayLengthDefineBug = function hasArrayLengthDefineBug() {
	// node v0.6 has a bug where array lengths can be Set but not Defined
	if (!hasPropertyDescriptors()) {
		return null;
	}
	try {
		return $defineProperty([], 'length', { value: 1 }).length !== 1;
	} catch (e) {
		// In Firefox 4-22, defining length on an array throws an exception.
		return true;
	}
};

module.exports = hasPropertyDescriptors;