We use Jest for unit testing in Volto. The popular
@testing-library/react is also
available for writing your tests. For every feature or component, a unit test is
mandatory in Volto core.
Jest is configured in
package.json, under the "jest" key.
Jest configuration override#
In CI or for testing addons, it's interesting to provide an alternate Jest configuration
or slightly modify it. Volto provide a way to do it using a
jest.config.js file or
pointing the test runner to a file of your choice, using
RAZZLE_JEST_CONFIG=my-custom-jest-config.js yarn test
Both configurations are merged in a way that the keys of the config provided override the initial (
package.json) default config, either in Volto or in your projects.
This is specially useful in CI while developing add-ons, so you can pass an specific configuration that deals with the addon config properly.
Add add-ons via environment variable for testing purposes#
Sometimes you need to enable different configurations and enable optional components (for example, testing purposes).
You can use the
ADDONS environment variable to define them.
ADDONS=test-addon,test-addon2 yarn start
See Environment variables for more information.
Developing Cypress tests#
Volto uses Cypress to run integration tests. When developing or debugging Cypress tests, it's useful to be able to replicate the test environment.
You can start Cypress by running:
This will open Cypress in a browser, where you can see the available registered tests and you can start them manually. You can even open the browser's developer console and inspect network traffic and logging errors.
Notice that we've started Cypress with a different
API_PATH. Cypress tests
need to communicate with Plone through XMLRPC, to do rollbacks and cleanups
after each test. To start Zope and Plone, run:
If your test fails and won't cleanup after itself, you may get errors about content that already exists, etc. Just restart the test acceptance server, as it uses a non-persistent database.
Finally, you can to start Volto with:
If you're developing in parallel the code and the test, you can start Volto in development mode by running:
RAZZLE_API_PATH=http://localhost:55001/plone yarn start