Nightmare

👍

Covered in this doc

• Visual regression testing for Nightmare
• Installing and importing @percy/nightmare
• Calling and configuring percySnapshot(<snapshotName>, <options>)

percy-nightmare on GitHub

📘

These docs apply to version v2.0.0 or later. Previous versions of @percy/nightmare are incompatible with what is described in this document. v1.x docs can be found here

Installation

$ npm install --save-dev @percy/cli @percy/nightmare

Usage

This is an example using the percySnapshot function.

const Nightmare = require('nightmare');
const percySnapshot = require('@percy/nightmare);

Nightmare()
  .goto('http://example.com')
  //... other actions ...
  .use(percySnapshot('Example Snapshot'))
  //... more actions ...
  .end()
  .then(() => {
    // ...
  })

Running the code above directly will result in the following logs:

$ node script.js
[percy] Percy is not running, disabling snapshots

When running with percy exec, and your project's PERCY_TOKEN, a new Percy build will be created and snapshots will be uploaded to your project.

$ export PERCY_TOKEN=[your-project-token]
$ percy exec -- node script.js
[percy] Percy has started!
[percy] Created build #1: https://percy.io/[your-project]
[percy] Running "node script.js"
[percy] Snapshot taken "Example Snapshot"
[percy] Stopping percy...
[percy] Finalized build #1: https://percy.io/[your-project]
[percy] Done!

Configuration

percySnapshot(name[, options])

• name (required) - The snapshot name; must be unique to each snapshot
• options - See per-snapshot configuration options

Global configuration

You can also configure Percy to use the same options over all snapshots. To see supported configuration including widths read our SDK configuration docs

Upgrading

Automatically with @percy/migrate

We built a tool to help automate migrating to the new CLI toolchain! Migrating can be done by running the following commands and following the prompts:

$ npx @percy/migrate
? Are you currently using @percy/nightmare? Yes
? Install @percy/cli (required to run percy)? Yes
? Migrate Percy config file? Yes
? Upgrade SDK to @percy/[email protected]? Yes

This will automatically run the changes described below for you.

Manually

Installing @percy/cli

If you're coming from a pre-2.0 version of this package, make sure to install @percy/cli after upgrading to retain any existing scripts that reference the Percy CLI command.

$ npm install --save-dev @percy/cli

Import change

If you're coming from a pre-2.0 version of this package, the percySnapshot function is now the default export.

// before
const { percySnapshot } = require('@percy/nightmare');

// after
const percySnapshot = require('@percy/nightmare');

Migrating Config

If you have a previous Percy configuration file, migrate it to the newest version with the config:migrate command:

$ percy config:migrate