Did not spy fs.createWriteStream, and it will create the file in the real file system

[axetroy]

import fs from 'node:fs'
import path from 'node:path'
import test from 'node:test'

import mock from 'mock-fs'

test.beforeEach(() => {
    mock({
        [import.meta.dirname]: {}
    })
})

test.afterEach(() => {
    mock.restore()
})

test('Test', async (t) => {
    // ❌ This will create the file in the real file system
    fs.createWriteStream(path.join(import.meta.dirname, 'testing-2024-11-13.001.log'))
    // ✅ This will not
    // fs.writeFileSync(path.join(import.meta.dirname, 'testing-2024-11-13.001.log'), 'hello world!')

    for (const file of fs.readdirSync(import.meta.dirname)) {
        console.log(file)
    }
})

Just create test file mock-fs.test.mjs

And then run the test with the following command

node --test --experimental-default-type=module