grunt-phantomcss

Automate CSS regression testing with PhantomCSS

Getting Started

This plugin requires Grunt ~0.4.1

If you haven't used Grunt before, be sure to check out the Getting Started guide, as it explains how to create a Gruntfile as well as install and use Grunt plugins. Once you're familiar with that process, you may install this plugin with this command:

npm install grunt-phantomcss --save-dev

Once the plugin has been installed, it may be enabled inside your Gruntfile with this line of JavaScript:

grunt.loadNpmTasks('grunt-phantomcss');

The "phantomcss" task

Overview

In your project's Gruntfile, add a section named phantomcss to the data object passed into grunt.initConfig().

grunt.initConfig({
  phantomcss: {
    options: {},
    your_target: {
      options: {
        screenshots: 'test/visual/screenshots/',
        results: 'results/visual/'
      },
      src: [
        'test/visual/**/*.js'
      ]
    }
  }
});

Options

src

Type: String|Array

The test files to run.

options.screenshots

Type: String
Default: './screenshots'

The screenshots directory where test fixtures (comparison screenshots) are stored. Baseline screenshots will be stored here on the first run if they're not present.

options.results

Type: String
Default: './results'

The directory to store source, diff, and failure screenshots after tests.

options.viewportSize

Type: Array
Default: [1280, 800]

The viewport size to test the site in [width, height] format. Useful when testing responsive layouts.

options.logLevel

Type: String
Default: error

The CasperJS log level. See CasperJS: Logging for details.

Usage Examples

Basic visual tests

Run tests in test/visual/ against comparison screenshots stored in test/visual/screenshots/, and put the resulting screenshots in results/visual/

grunt.initConfig({
  phantomcss: {
    options: {
      screenshots: 'test/visual/screenshots/',
      results: 'results/visual/'
    },
    src: [
      'test/visual/**/*.js'
    ]
  }
});

Responsive layout testing

Run tests in test/visual/ against comparison screenshots for destop and mobile.

grunt.initConfig({
  phantomcss: {
    desktop: {
      options: {
        screenshots: 'test/visual/desktop/',
        results: 'results/visual/desktop',
        viewportSize: [1024, 768]
      },
      src: [
        'test/visual/**.js'
      ]
    },
    mobile: {
      options: {
        screenshots: 'test/visual/mobile/',
        results: 'results/visual/mobile',
        viewportSize: [320, 480]
      },
      src: [
        'test/visual/**.js'
      ]
    }
  },
});

Sample test file

Test files should do the following:

• Start CasperJS with the URL you want to test
• Manipulate the page in some way
• Take screenshots

casper.start('http://localhost:3000/')
.then(function() {
  phantomcss.screenshot('#todo-app', 'Main app');
})
.then(function() {
  casper.fill('form.todo-form', {
    todo: 'Item1'
  }, true);

  phantomcss.screenshot('#todo-app', 'Item added');
})
.then(function() {
  casper.click('.todo-done');

  phantomcss.screenshot('#todo-app', 'Item checked off');
});

You can also load a local file by specifying a path (relative to the Gruntfile):

casper.start('build/client/index.html')
.then(function() {
  // ...
});

Multiple Test Files

Your first test file should use casper.start

casper.start('http://localhost:3000/')
.then(function() {
  phantomcss.screenshot('#todo-app', 'Main app');
})
.then(function() {
  casper.fill('form.todo-form', {
    todo: 'Item1'
  }, true);

  phantomcss.screenshot('#todo-app', 'Item added');
});

Subsequent files should call casper.then to continue the previous test.

casper.then(function() {
  casper.click('.todo-done');

  phantomcss.screenshot('#todo-app', 'Item checked off');
});

You can also use casper.thenOpen to load a new url and continue testing in subsequent files instead of casper.start.

See the CasperJS documentation and the PhantomCSS documentation for more information on using CasperJS and PhantomCSS.

Contributing

In lieu of a formal styleguide, take care to maintain the existing coding style. Add unit tests for any new or changed functionality. Lint and test your code using Grunt.

Release History

• 2014-02-23   v0.2.2   Added multiple file example to README.md
• 2014-02-07   v0.2.1   Fixed ResembleJS path issue
• 2014-01-07   v0.2.0   Merged updates from Larry Davis
• 2013-10-24   v0.1.1   Added the ability to use an external server
• 2013-10-24   v0.1.0   Initial Release