JSTests/test262/test/built-ins/Promise/allSettled/reject-element-function-property-order.js

// Copyright (C) 2020 ExE Boss. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-createbuiltinfunction
description: Promise.allSettled reject element function property order
info: |
  Set order: "length", "name"
features: [Promise.allSettled]
---*/

var rejectElementFunction;
var thenable = {
  then: function(_, reject) {
    rejectElementFunction = reject;
  }
};

function NotPromise(executor) {
  executor(function() {}, function() {});
}
NotPromise.resolve = function(v) {
  return v;
};
Promise.allSettled.call(NotPromise, [thenable]);

var propNames = Object.getOwnPropertyNames(rejectElementFunction);
var lengthIndex = propNames.indexOf("length");
var nameIndex = propNames.indexOf("name");

assert(lengthIndex >= 0 && nameIndex === lengthIndex + 1,
  "The `length` property comes before the `name` property on built-in functions");