vue-testing-library

Lightweight adapter allowing dom-testing-library to be used to test Vue.js components built on top of @vue/test-utils

---

     

  

This library

The vue-testing-library is a an adapter that enables Vue testing using the framework-agnostic DOM testing library dom-testing-library

• Installation
• Usage
  • render
  • fireEvent
  • wait
• Examples
• LICENSE

Installation

This module is distributed via npm which is bundled with node and should be installed as one of your project's devDependencies:

npm install --save-dev vue-testing-library

Usage

npm install --save-dev vue-testing-library
                       jest
                       vue-jest
                       babel-jest
                       babel-preset-env
                       babel-plugin-transform-runtime

// package.json
  "scripts": {
    "test": "jest"
  }

  "jest": {
    "moduleDirectories": [
      "node_modules",
      "src"
    ],
    "moduleFileExtensions": [
      "js",
      "vue"
    ],
    "testPathIgnorePatterns": [
      "/node_modules/"
    ],
    "transform": {
      "^.+\\.js$": "<rootDir>/node_modules/babel-jest",
      ".*\\.(vue)$": "<rootDir>/node_modules/vue-jest"
    }
  }

// .babelrc
{
  "presets": [
    ["env", {
      "modules": false,
      "targets": {
        "browsers": ["> 1%", "last 2 versions", "not ie <= 8"]
      }
    }]
  ],
  "plugins": [
    "transform-runtime"
  ],
  "env": {
    "test": {
      "presets": ["env"]
    }
  }
}

// src/TestComponent.vue
<template>
  <div>
    <span data-testid="test1">Hello World</span>
  </div>
</template>

// src/TestComponent.spec.js
import 'jest-dom/extend-expect'
import { render } from 'vue-testing-library'
import TestComponent from './TestComponent'

test('should render HelloWorld', () => {
  const { queryByTestId } = render(TestComponent)
  expect(queryByTestId('test1')).toHaveTextContent('Hello World')
})

render

The render function takes up to 3 parameters and returns an object with some helper methods

1. Component - the Vue component to be tested.
2. RenderOptions - an object containing additional information to be passed to @vue/test-utils mount. This can be:

• props - The component props to be passed to TestComponent
• store - The object definition of a Vuex store, if present render will configure a Vuex store and pass to mount.
• routes - A set of routes, if present render will configure VueRouter and pass to mount.

3. configurationCb - A callback to be called passing the Vue instance when created. This allows 3rd party plugins to be installed prior to mount.

fireEvent

Lightweight wrapper around DOM element events and methods. Will call wait, so can be awaited to allow effects to propagate.

wait

When in need to wait for non-deterministic periods of time you can use wait, to wait for your expectations to pass. The wait function is a small wrapper around the wait-for-expect module.

Waiting can be very important in Vue components, @vue/test-utils has succeeded in making the majority of updates happen synchronously however there are occasions when wait will allow the DOM to update. For example, see here

Examples

You'll find examples of testing with different libraries in the test directory. Some included are:

• vuex
• vue-router
• vee-validate

Feel free to contribute more!

LICENSE

MIT

CONTRIBUTORS