es.object.define-property.js

import { DESCRIPTORS } from '../helpers/constants';

QUnit.test('Object.defineProperty', assert => {
  const { defineProperty, create } = Object;
  assert.isFunction(defineProperty);
  assert.arity(defineProperty, 3);
  assert.name(defineProperty, 'defineProperty');
  assert.looksNative(defineProperty);
  assert.nonEnumerable(Object, 'defineProperty');
  const source = {};
  const result = defineProperty(source, 'q', {
    value: 42,
  });
  assert.same(result, source);
  assert.same(result.q, 42);

  if (DESCRIPTORS) {
    // eslint-disable-next-line prefer-arrow-callback -- required for testing
    assert.same(defineProperty(function () { /* empty */ }, 'prototype', {
      value: 42,
      writable: false,
    }).prototype, 42, 'function prototype with non-writable descriptor');
  }

  assert.throws(() => defineProperty(42, 1, {}));
  assert.throws(() => defineProperty({}, create(null), {}));
  assert.throws(() => defineProperty({}, 1, 1));
});

QUnit.test('Object.defineProperty.sham flag', assert => {
  assert.same(Object.defineProperty.sham, DESCRIPTORS ? undefined : true);
});