1// Flags: --frozen-intrinsics
2'use strict';
3require('../common');
4const assert = require('assert');
5
6assert.throws(
7  () => Object.defineProperty = 'asdf',
8  TypeError
9);
10
11// Ensure we can extend Console
12{
13  class ExtendedConsole extends console.Console {}
14
15  const s = new ExtendedConsole(process.stdout);
16  const logs = [];
17  s.log = (msg) => logs.push(msg);
18  s.log('custom');
19  s.log = undefined;
20  assert.strictEqual(s.log, undefined);
21  assert.strictEqual(logs.length, 1);
22  assert.strictEqual(logs[0], 'custom');
23}
24
25// Ensure we can write override Object prototype properties on instances
26{
27  const o = {};
28  o.toString = () => 'Custom toString';
29  assert.strictEqual(o + 'asdf', 'Custom toStringasdf');
30  assert.strictEqual(Object.getOwnPropertyDescriptor(o, 'toString').enumerable,
31                     true);
32}
33
34// Ensure we can not override globalThis
35{
36  assert.throws(() => { globalThis.globalThis = null; },
37                { name: 'TypeError' });
38  assert.strictEqual(globalThis.globalThis, globalThis);
39}
40
41// Ensure that we cannot override console properties.
42{
43  const { log } = console;
44
45  assert.throws(() => { console.log = null; },
46                { name: 'TypeError' });
47  assert.strictEqual(console.log, log);
48}
49