node-testing

Testing Style Guide

Testing Frameworks

• use vitest

Expectations

Always prefer inline snapshot matching whenever possible. If necessary, have local normalization/sanitization functions to replace things that are noisy or unstable, like timestamps or error stacks.

Always prefer toThrowMatchingInlineSnapshot() over naked toThrow() or toThrow() with a regex.

Test Organization

Tests are in src/test

Mocking HTTP Requests

We use msw. We use v2 so don't use the v1 api.

File I/O

Use node-fixturify against a temp directory. Do not mock file system operations. Set XDG variables like XDG_DATA_HOME, XDG_STATE_HOME, XDG_CONFIG_HOME &c. so that files are written to the temp directory.

IMPORTANT: when setting an XDG variable be sure to call Logger.reset. The logging utilities use a singleton that only checks for the XDG directory on initialization. Be sure to call Logger.reset in afterEach and not in beforeEach so you don't poison future tests.

Here are the usage docs from fixturify's README

const fixturify = require('fixturify')

const obj = {
  'foo.txt': 'foo.txt contents',
  'subdir': {
    'bar.txt': 'bar.txt contents'
  }
}

fixturify.writeSync('testdir', obj) // write it to disk

fixturify.readSync('testdir') // => deep-equals obj

fixturify.readSync('testdir', { globs: ['foo*'] }) // glob support
// => { foo.txt: 'foo.text contents' }

fixturify.readSync('testdir', { ignore: ['foo*'] }) // glob support
// => { subdir: { bar.txt: 'bar.text contents' } }

fixturify.writeSync('testDir', {
  'subdir': { 'bar.txt': null }
}) // remove subdir/bar.txt

fixturify.readSync('testdir') // => { foo.txt: 'foo.text contents' }

fixturify.writeSync('testDir', {
  'subdir': null
}) // remove subdir/

const fixturify = require('fixturify')

const obj = {
  'subdir': {
    'foo.txt': 'foo.txt contents'
  },
  'emptydir': {}
}

fixturify.writeSync('testdir', obj) // write it to disk

fixturify.readSync('testdir', { ignoreEmptyDirs: true })
// => { subdir: { foo.txt': 'foo.txt contents' } }