Visual Regression Testing with PhantomCSS [Front Porch 2016]

@jonbellah - jonbellah.com/talks/frontporch Regression Testing with PhantomCSS Visual

@jonbellah - jonbellah.com/talks/frontporch Lead Front-End Engineer @jonbellah

@jonbellah - jonbellah.com/talks/frontporch DISCLAIMER

@jonbellah - jonbellah.com/talks/frontporch Regression Testing with my personal favorite tool
Visual

@jonbellah - jonbellah.com/talks/frontporch selenium wraith succss siteeffect huxley dpxdt css
critic shoov snap and compare cactus hardy applitools specter needle

@jonbellah - jonbellah.com/talks/frontporch ? What the heck is Visual Regression
Testing

@jonbellah - jonbellah.com/talks/frontporch visual changes Automated testing of

@jonbellah - jonbellah.com/talks/frontporch

@jonbellah - jonbellah.com/talks/frontporch “But I change CSS because I want
things to look different…”

@jonbellah - jonbellah.com/talks/frontporch ? important So why is this

@jonbellah - jonbellah.com/talks/frontporch projects iterating on

@jonbellah - jonbellah.com/talks/frontporch projects refactoring

@jonbellah - jonbellah.com/talks/frontporch projects distributed

@jonbellah - jonbellah.com/talks/frontporch projects open source

@jonbellah - jonbellah.com/talks/frontporch helps prevent unintended changes

@jonbellah - jonbellah.com/talks/frontporch automate your workflow

@jonbellah - jonbellah.com/talks/frontporch Manual testing is expensive

@jonbellah - jonbellah.com/talks/frontporch is imperfect Manual testing

@jonbellah - jonbellah.com/talks/frontporch attention to detail” “but I have excellent

@jonbellah - jonbellah.com/talks/frontporch Actually…

@jonbellah - jonbellah.com/talks/frontporch TERRIBLE Humans are at spotting changes

@jonbellah - jonbellah.com/talks/frontporch & McConkie Currie 1996

@jonbellah - jonbellah.com/talks/frontporch Change Blindness

@jonbellah - jonbellah.com/talks/frontporch A perceptual phenomenon that occurs when changes
in a visual stimulus are made without the observer noticing Source: Wikipedia

@jonbellah - jonbellah.com/talks/frontporch 20% of an image can change without
the observer noticing

@jonbellah - jonbellah.com/talks/frontporch The Tools

@jonbellah - jonbellah.com/talks/frontporch PhantomCSS https://github.com/Huddle/PhantomCSS

@jonbellah - jonbellah.com/talks/frontporch PhantomJS or SlimerJS - A headless browser.

CasperJS - Navigation scripting and testing utility.

CasperJS - Navigation scripting and testing utility. ResembleJS - A library for making image comparisons.

@jonbellah - jonbellah.com/talks/frontporch GruntJS

@jonbellah - jonbellah.com/talks/frontporch The Implementation

@jonbellah - jonbellah.com/talks/frontporch Grunt setting up

@jonbellah - jonbellah.com/talks/frontporch $ cd path/to/your-project

@jonbellah - jonbellah.com/talks/frontporch $ npm install @micahgodbolt/grunt-phantomcss --save-dev

@jonbellah - jonbellah.com/talks/frontporch grunt.loadNpmTasks('@micahgodbolt/grunt-phantomcss'); grunt.initConfig({ phantomcss: { desktop: { options:
{ screenshots: 'baselines/desktop', results: 'results/desktop', viewportSize: [1280, 800] }, src: [ 'test/visual/start.js', 'test/visual/*-test.js' ] } } });

@jonbellah - jonbellah.com/talks/frontporch options: { screenshots: 'baselines/desktop', results: 'results/desktop', viewportSize:
[1280, 800], mismatchTolerance: 0.05, rootUrl: 'http://localhost:3000/' // Optional }

@jonbellah - jonbellah.com/talks/frontporch Testing Different Breakpoints

@jonbellah - jonbellah.com/talks/frontporch $mq-breakpoints: ( mobile: 320px, tablet: 740px, desktop:
980px, wide: 1300px ); Sass MQ

@jonbellah - jonbellah.com/talks/frontporch phantomcss: { desktop: { options: { screenshots:
'baselines/desktop', results: 'results/desktop', viewportSize: [1024, 768] } }, mobile: { options: { screenshots: 'baselines/mobile', results: 'results/mobile', viewportSize: [320, 480] } } }

@jonbellah - jonbellah.com/talks/frontporch Writing Your First Tests

@jonbellah - jonbellah.com/talks/frontporch phantom.casperTest = true; casper.start(); start.js

@jonbellah - jonbellah.com/talks/frontporch phantom.casperTest = true; casper.start(); start.js src: [
'test/visual/start.js', 'test/visual/*-test.js' ] Gruntfile.js

@jonbellah - jonbellah.com/talks/frontporch casper.thenOpen('http://mysite.dev/') .then(function() { phantomcss.screenshot('.site-header', 'site-header'); }); header-test.js

@jonbellah - jonbellah.com/talks/frontporch Test Suite Structure

@jonbellah - jonbellah.com/talks/frontporch focus on components

@jonbellah - jonbellah.com/talks/frontporch Scripting Interactions

@jonbellah - jonbellah.com/talks/frontporch CasperJS

@jonbellah - jonbellah.com/talks/frontporch casper.click(); casper.download(); casper.fill(); casper.scrollTo(); casper.reload(); casper.mouseEvent(); docs.casperjs.org

@jonbellah - jonbellah.com/talks/frontporch casper.then(function() { this.mouse.move('.button'); phantomcss.screenshot('.button'); });

@jonbellah - jonbellah.com/talks/frontporch casper.start('http://mysite.dev/wp-admin/', function() { this.fill('#loginform', { 'log': 'admin',
'pwd': 'password' }, true); this.click('#wp-submit'); });

@jonbellah - jonbellah.com/talks/frontporch Running Your Tests

@jonbellah - jonbellah.com/talks/frontporch $ grunt phantomcss

@jonbellah - jonbellah.com/talks/frontporch Failing Tests

@jonbellah - jonbellah.com/talks/frontporch visual regression testing tools ARE NOT PERFECT

@jonbellah - jonbellah.com/talks/frontporch Challenges

@jonbellah - jonbellah.com/talks/frontporch 1 content dynamic

@jonbellah - jonbellah.com/talks/frontporch replacement dynamic

@jonbellah - jonbellah.com/talks/frontporch Faker.prototype.home = function( posts ) { var
$ = jQuery, post = posts[5]; var title = post.title, author = post.author.name, date = post.date, excerpt = post.excerpt; // Hero var $hero = $('#hero'); $hero.find('.-text .entry-title').html( title ); $hero.find('.-text .author > a').html( author ); $hero.find('.-text .entry-content p').html( excerpt ); }

@jonbellah - jonbellah.com/talks/frontporch var core = require( './core.js' ), Faker
= require( ‘./faker.js’), posts = core.getData(), faker = new Faker(); casper.thenOpen( core.getSiteURL() ) .thenEvaluate( faker.home, posts ) .then( function() { phantomcss.screenshot( '#hero .-text', 'hero- post' ); });

@jonbellah - jonbellah.com/talks/frontporch guides style

@jonbellah - jonbellah.com/talks/frontporch mdcss

@jonbellah - jonbellah.com/talks/frontporch /*--- title: Buttons section: Base CSS ---
Button styles can be applied to any element. Typically you'll want to use either a `<button>` or an `<a>` element: ```example:html <button class="btn">Click</button> <a class="btn" href="/some-page">Some Page</a> ``` */ .btn { background-color: black; color: white; }

@jonbellah - jonbellah.com/talks/frontporch 2animations & web fonts

@jonbellah - jonbellah.com/talks/frontporch 3 distribution

@jonbellah - jonbellah.com/talks/frontporch LOCAL URL not everyone uses the same

@jonbellah - jonbellah.com/talks/frontporch var localURL = grunt.option( 'url' ); grunt.registerTask(
'test', function() { if ( localURL ) { grunt.log.writeln( 'Local URL: ' + localURL ); grunt.file.write( 'test/visual/.local_url', localURL ); } grunt.task.run(['phantomcss']); });

@jonbellah - jonbellah.com/talks/frontporch var fs = require('fs'), siteURL; try {
siteURL = fs.read( 'test/visual/.local_url' ); } catch(err) { siteURL = (typeof siteURL === 'undefined') ? 'http://local.wordpress.dev' : siteURL; } casper.thenOpen(siteURL + '/path/to/template');

@jonbellah - jonbellah.com/talks/frontporch OPERATING SYSTEM not everyone uses the same

@jonbellah - jonbellah.com/talks/frontporch Continuous Integration

@jonbellah - jonbellah.com/talks/frontporch CAUTION WORK IN PROGRESS

@jonbellah - jonbellah.com/talks/frontporch Questions?

Visual Regression Testing with PhantomCSS [Fron...

Visual Regression Testing with PhantomCSS [Front Porch 2016]

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