Cypress Visual Regression

Module for adding visual regression testing to Cypress.

NOTE: This is forked from mjhea0 who did all the hard work this was created just to remove the dependency on image-magik to see if it could be done directly with blink so no external install needed

I've currently taken the type switch out so the base images is a manual process.

Getting Started

Install:

$ npm install cypress-blink-test

Add the following config to your cypress.json file:

{
  "screenshotsFolder": "cypress/snapshots/actual",
  "trashAssetsBeforeRuns": true
}

Add the plugin to cypress/plugins/index.js:

const getCompareSnapshotsPlugin = require('cypress-visual-regression/dist/plugin');

module.exports = (on) => {
  getCompareSnapshotsPlugin(on);
};

Add the command to cypress/support/commands.js:

const compareSnapshotCommand = require('cypress-visual-regression/dist/command');

compareSnapshotCommand();

To Use

Add cy.compareSnapshot('home'); in your tests specs whenever you want to test for visual regressions, making sure to replace home with a relevant name. You can also add an optional error threshold: Value can range from 0.00 (no difference) to 1.00 (every pixel is different). So, if you enter an error threshold of 0.50, the test would fail only if 0.51 percent of pixels are different.

Find regressions:

$ ./node_modules/.bin/cypress run 

Example

TODO

1. Allow end user to customize options (screenshot directory)
2. Test functionality of taking screenshots without running visual regression
3. Prevent "base" tests runs from actually running the regular Cypress tests