Table of Contents
The Problem
You want to write maintainable tests for your Svelte components.
This Solution
@testing-library/svelte is a lightweight library for testing Svelte
components. It provides functions on top of svelte and
@testing-library/dom so you can mount Svelte components and query their
rendered output in the DOM. Its primary guiding principle is:
The more your tests resemble the way your software is used, the more
confidence they can give you.
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 @testing-library/svelte
This library supports svelte versions 3, 4, and 5.
You may also be interested in installing @testing-library/jest-dom so you can
use the custom jest matchers.
Setup
We recommend using @testing-library/svelte with Vitest as your test
runner. To get started, add the svelteTesting plugin to your Vite or Vitest
config.
// vite.config.js
import { svelte } from '@sveltejs/vite-plugin-svelte'
+ import { svelteTesting } from '@testing-library/svelte/vite'
export default defineConfig({
plugins: [
svelte(),
+ svelteTesting(),
]
});
See the setup docs for more detailed setup instructions, including for other
test runners like Jest.
Auto-cleanup
In Vitest (via the svelteTesting plugin) and Jest (via the beforeEach and afterEach globals),
this library will automatically setup and cleanup the test environment before and after each test.
To do your own cleanup, or if you're using another framework, call the setup and cleanup functions yourself:
import { cleanup, render, setup } from '@testing-library/svelte'
setup()
render()
cleanup()
To disable auto-cleanup in Vitest, set the autoCleanup option of the plugin to false:
svelteTesting({ autoCleanup: false })
To disable auto-cleanup in Jest and other frameworks with global test hooks,
set the STL_SKIP_AUTO_CLEANUP environment variable:
STL_SKIP_AUTO_CLEANUP=1 jest
Docs
See the docs over at the Testing Library website.
Issues
Looking to contribute? Look for the Good First Issue
label.
🐛 Bugs
Please file an issue for bugs, missing documentation, or unexpected behavior.
See Bugs
💡 Feature Requests
Please file an issue to suggest new features. Vote on feature requests by adding
a 👍. This helps maintainers prioritize what to work on.
See Feature Requests
❓ Questions
For questions related to using the library, please visit a support community
instead of filing an issue on GitHub.
Contributors
Thanks goes to these people (emoji key):
This project follows the all-contributors specification.
Contributions of any kind welcome!