Unit testing Svelte components in Cypress E2E test runner with Webpack

Requires Node version 6 or above.

npm install --save cypress-svelte-unit-test
npm install --save-dev @cypress/webpack-preprocessor

Then, configure Cypress to use the plugin in cypress/plugins/index.js:

const webpack = require('@cypress/webpack-preprocessor')

module.exports = on => {
  const options = {
    // send in the options from your webpack.config.js, so it works the same
    // as your app's code
    webpackOptions: require('../webpack.config.js')
  }

  on('file:preprocessor', webpack(options))
}

This component adaptor is meant for Svelte v3. If you need Svelte v2 support, check out branch svelte-v2

Import your Svelte component and mount using the provided function. Pass component options and global document options (like a global CSS)

/// <reference types="cypress" />
import App from '../components/ChainedBalls.svelte'
import mount from 'cypress-svelte-unit-test'

describe('SVG animation', () => {
  it('shows chained balls', () => {
    cy.viewport(960, 500)
    const style = `
      line {
        stroke: gray;
        stroke-width: 2px;
      }
    `
    mount(App, {
      props: {
        width: 960,
        height: 500
      }
    }, { style })
    cy.get('circle').should('have.length', 50)
  })
})

Svelte components copied from https://svelte.dev/examples

All components are in cypress/components folder, all test files in cypress/integration

Same feature for unit testing components from other framesworks using Cypress

• cypress-vue-unit-test
• cypress-react-unit-test
• cypress-cycle-unit-test
• cypress-svelte-unit-test
• cypress-angular-unit-test
• cypress-hyperapp-unit-test
• cypress-angularjs-unit-test

Author: Gleb Bahmutov <[email protected]> © 2018

• @bahmutov
• glebbahmutov.com
• blog

License: MIT - do anything with the code, but don't blame me if it does not work.

Support: if you find any problems with this module, email / tweet / open issue on Github

Copyright (c) 2018 Gleb Bahmutov <[email protected]>

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.