/
test-freeze-intrinsics.js
48 lines (41 loc) · 1.21 KB
/
test-freeze-intrinsics.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
// Flags: --frozen-intrinsics
'use strict';
require('../common');
const assert = require('assert');
assert.throws(
() => Object.defineProperty = 'asdf',
TypeError
);
// Ensure we can extend Console
{
class ExtendedConsole extends console.Console {}
const s = new ExtendedConsole(process.stdout);
const logs = [];
s.log = (msg) => logs.push(msg);
s.log('custom');
s.log = undefined;
assert.strictEqual(s.log, undefined);
assert.strictEqual(logs.length, 1);
assert.strictEqual(logs[0], 'custom');
}
// Ensure we can write override Object prototype properties on instances
{
const o = {};
o.toString = () => 'Custom toString';
assert.strictEqual(o + 'asdf', 'Custom toStringasdf');
assert.strictEqual(Object.getOwnPropertyDescriptor(o, 'toString').enumerable,
true);
}
// Ensure we can not override globalThis
{
assert.throws(() => { globalThis.globalThis = null; },
{ name: 'TypeError' });
assert.strictEqual(globalThis.globalThis, globalThis);
}
// Ensure that we cannot override console properties.
{
const { log } = console;
assert.throws(() => { console.log = null; },
{ name: 'TypeError' });
assert.strictEqual(console.log, log);
}