ToPropertyDescriptor.js

'use strict';

var has = require('has');

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

var $TypeError = GetIntrinsic('%TypeError%');

var Type = require('./Type');
var ToBoolean = require('./ToBoolean');
var IsCallable = require('./IsCallable');

// https://262.ecma-international.org/5.1/#sec-8.10.5

module.exports = function ToPropertyDescriptor(Obj) {
	if (Type(Obj) !== 'Object') {
		throw new $TypeError('ToPropertyDescriptor requires an object');
	}

	var desc = {};
	if (has(Obj, 'enumerable')) {
		desc['[[Enumerable]]'] = ToBoolean(Obj.enumerable);
	}
	if (has(Obj, 'configurable')) {
		desc['[[Configurable]]'] = ToBoolean(Obj.configurable);
	}
	if (has(Obj, 'value')) {
		desc['[[Value]]'] = Obj.value;
	}
	if (has(Obj, 'writable')) {
		desc['[[Writable]]'] = ToBoolean(Obj.writable);
	}
	if (has(Obj, 'get')) {
		var getter = Obj.get;
		if (typeof getter !== 'undefined' && !IsCallable(getter)) {
			throw new $TypeError('getter must be a function');
		}
		desc['[[Get]]'] = getter;
	}
	if (has(Obj, 'set')) {
		var setter = Obj.set;
		if (typeof setter !== 'undefined' && !IsCallable(setter)) {
			throw new $TypeError('setter must be a function');
		}
		desc['[[Set]]'] = setter;
	}

	if ((has(desc, '[[Get]]') || has(desc, '[[Set]]')) && (has(desc, '[[Value]]') || has(desc, '[[Writable]]'))) {
		throw new $TypeError('Invalid property descriptor. Cannot both specify accessors and a value or writable attribute');
	}
	return desc;
};