I'm trying to migrate from AVA to Jest. In AVA you can set ava.setup
, in which you set the jsdom
environment. For example, creating the DOM structure and doing necessary polyfills (localStorage).
How do I accomplish that in Jest? Currently, I'm using beforeEach
in each test suite, which doesn't feel like the best solution.
Thanks in advance!
Great question.
Jest actually ships with jsdom
and the environment already configured. You can override it with the testEnvironment
setting.
If you need to set up more aspects of the environment though, you can use the setupTestFrameworkScriptFile
setting to point to a file that executes before all of your tests run.
For example, if you need window.yourVar
to be available on the window for all your tests, you would add this to your package.json
:
"jest": {
"setupTestFrameworkScriptFile": "tests/setup.js"
}
And in tests/setup.js:
Object.defineProperty(window, 'yourVar', { value: 'yourValue' });