brittle-snapshot

Snapshot testing for brittle. One snapshot file per test file, multiple snapshots per file.

Install

npm i brittle-snapshot

Usage

const test = require('brittle')
const { matchSnapshot } = require('brittle-snapshot')

test('render heading', (t) => {
  const html = render('<h1>hello</h1>')

  matchSnapshot(t, html)
  matchSnapshot(t, render('<h1>world</h1>'), 'second heading')
})

Snapshots are written to a __snapshots__ directory alongside the calling test file, named after it:

test/
  render.js
  __snapshots__/
    render.snap

Each .snap file contains all snapshots for that test file:

=== render heading > 1 ===
<h1>hello</h1>
=== render heading > second heading ===
<h1>world</h1>

API

matchSnapshot(t, source, [desc])

Compare source against a stored snapshot using character-level diffing.

matchSnapshotCSS(t, source, [desc])

Compare using CSS-aware diffing.

matchSnapshotJSON(t, source, [desc])

Compare using JSON-aware diffing.

All functions take:

• t — a brittle test instance
• source — string to snapshot
• desc — optional label for the snapshot key (defaults to an auto-incrementing counter)

Updating snapshots

Run with --update or -u to overwrite existing snapshots:

bare test/render.js --update

or

npm test -- --update

License

Apache-2.0