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'use strict';
var GetIntrinsic = require('get-intrinsic');
var $TypeError = GetIntrinsic('%TypeError%');
var DefineOwnProperty = require('../helpers/DefineOwnProperty');
var isPropertyDescriptor = require('../helpers/isPropertyDescriptor');
var isSamePropertyDescriptor = require('../helpers/isSamePropertyDescriptor');
var FromPropertyDescriptor = require('./FromPropertyDescriptor');
var IsAccessorDescriptor = require('./IsAccessorDescriptor');
var IsDataDescriptor = require('./IsDataDescriptor');
var IsGenericDescriptor = require('./IsGenericDescriptor');
var IsPropertyKey = require('./IsPropertyKey');
var SameValue = require('./SameValue');
var Type = require('./Type');
// https://262.ecma-international.org/6.0/#sec-validateandapplypropertydescriptor
// https://262.ecma-international.org/8.0/#sec-validateandapplypropertydescriptor
// eslint-disable-next-line max-lines-per-function, max-statements
module.exports = function ValidateAndApplyPropertyDescriptor(O, P, extensible, Desc, current) {
// this uses the ES2017+ logic, since it fixes a number of bugs in the ES2015 logic.
var oType = Type(O);
if (oType !== 'Undefined' && oType !== 'Object') {
throw new $TypeError('Assertion failed: O must be undefined or an Object');
}
if (Type(extensible) !== 'Boolean') {
throw new $TypeError('Assertion failed: extensible must be a Boolean');
}
if (!isPropertyDescriptor({
Type: Type,
IsDataDescriptor: IsDataDescriptor,
IsAccessorDescriptor: IsAccessorDescriptor
}, Desc)) {
throw new $TypeError('Assertion failed: Desc must be a Property Descriptor');
}
if (Type(current) !== 'Undefined' && !isPropertyDescriptor({
Type: Type,
IsDataDescriptor: IsDataDescriptor,
IsAccessorDescriptor: IsAccessorDescriptor
}, current)) {
throw new $TypeError('Assertion failed: current must be a Property Descriptor, or undefined');
}
if (oType !== 'Undefined' && !IsPropertyKey(P)) {
throw new $TypeError('Assertion failed: if O is not undefined, P must be a Property Key');
}
if (Type(current) === 'Undefined') {
if (!extensible) {
return false;
}
if (IsGenericDescriptor(Desc) || IsDataDescriptor(Desc)) {
if (oType !== 'Undefined') {
DefineOwnProperty(
IsDataDescriptor,
SameValue,
FromPropertyDescriptor,
O,
P,
{
'[[Configurable]]': Desc['[[Configurable]]'],
'[[Enumerable]]': Desc['[[Enumerable]]'],
'[[Value]]': Desc['[[Value]]'],
'[[Writable]]': Desc['[[Writable]]']
}
);
}
} else {
if (!IsAccessorDescriptor(Desc)) {
throw new $TypeError('Assertion failed: Desc is not an accessor descriptor');
}
if (oType !== 'Undefined') {
return DefineOwnProperty(
IsDataDescriptor,
SameValue,
FromPropertyDescriptor,
O,
P,
Desc
);
}
}
return true;
}
if (IsGenericDescriptor(Desc) && !('[[Configurable]]' in Desc) && !('[[Enumerable]]' in Desc)) {
return true;
}
if (isSamePropertyDescriptor({ SameValue: SameValue }, Desc, current)) {
return true; // removed by ES2017, but should still be correct
}
// "if every field in Desc is absent, return true" can't really match the assertion that it's a Property Descriptor
if (!current['[[Configurable]]']) {
if (Desc['[[Configurable]]']) {
return false;
}
if ('[[Enumerable]]' in Desc && !Desc['[[Enumerable]]'] === !!current['[[Enumerable]]']) {
return false;
}
}
if (IsGenericDescriptor(Desc)) {
// no further validation is required.
} else if (IsDataDescriptor(current) !== IsDataDescriptor(Desc)) {
if (!current['[[Configurable]]']) {
return false;
}
if (IsDataDescriptor(current)) {
if (oType !== 'Undefined') {
DefineOwnProperty(
IsDataDescriptor,
SameValue,
FromPropertyDescriptor,
O,
P,
{
'[[Configurable]]': current['[[Configurable]]'],
'[[Enumerable]]': current['[[Enumerable]]'],
'[[Get]]': undefined
}
);
}
} else if (oType !== 'Undefined') {
DefineOwnProperty(
IsDataDescriptor,
SameValue,
FromPropertyDescriptor,
O,
P,
{
'[[Configurable]]': current['[[Configurable]]'],
'[[Enumerable]]': current['[[Enumerable]]'],
'[[Value]]': undefined
}
);
}
} else if (IsDataDescriptor(current) && IsDataDescriptor(Desc)) {
if (!current['[[Configurable]]'] && !current['[[Writable]]']) {
if ('[[Writable]]' in Desc && Desc['[[Writable]]']) {
return false;
}
if ('[[Value]]' in Desc && !SameValue(Desc['[[Value]]'], current['[[Value]]'])) {
return false;
}
return true;
}
} else if (IsAccessorDescriptor(current) && IsAccessorDescriptor(Desc)) {
if (!current['[[Configurable]]']) {
if ('[[Set]]' in Desc && !SameValue(Desc['[[Set]]'], current['[[Set]]'])) {
return false;
}
if ('[[Get]]' in Desc && !SameValue(Desc['[[Get]]'], current['[[Get]]'])) {
return false;
}
return true;
}
} else {
throw new $TypeError('Assertion failed: current and Desc are not both data, both accessors, or one accessor and one data.');
}
if (oType !== 'Undefined') {
return DefineOwnProperty(
IsDataDescriptor,
SameValue,
FromPropertyDescriptor,
O,
P,
Desc
);
}
return true;
};