ReferenceError: EventTarget is not defined in node<16

• @testing-library/user-event version: 14.0.0-beta.3

Relevant code or config

new EventTarget()

Problem description:

EventTarget does not exist in older node versions. Importing user-event results in a ReferenceError because: https://github.com/testing-library/user-event/blob/2c5d9f1369301539826879f95c9f6093f676e2bb/src/utils/dataTransfer/Clipboard.ts#L34

Suggested solution:

Either

• polyfill
• user-event requires a DOM implementation which requires EventTarget so any DOM implementation should already ship with a polyfill. We might as well just ask our users to set EventTarget globally if they use a DOM implementation that does not already do so in an older node environment.

[make-github-pseudonymous-again]

OK. I may have had too much enthusiasm when the first render-only tests passed. I probably need to do what is explained here for the interactive tests to work. Thanks for taking the time to lead me on the path of solution.

[make-github-pseudonymous-again]

I managed to make it work using @testing-library/user-event v13.5.0 instead of v14.0.0-beta.x. ~It seems my testing environment already sets up global.window and global.document but not document or window or global.EventTarget.~ Attempting to polyfill only EventTarget produces more errors. Attempting to just import jsdom breaks everything (without even trying to polyfill, I’ve tried it all the way down to v16.5.1).

I found something that works for now…

PS: OK I figured it out. Meteor runs tests both for the server and for the client. The server environment has no window whereas the client environment does have one. I was confused because I was convinced my client test would only run on the client (it was surrounded by if (Meteor.isClient) { ... }. But the import statements are executed on both, and that’s what breaks the server run. So two solutions: dynamic imports inside the client block, or client-only tests. Still deciding on which solution works best.