docs: update Vitest instructions for jest-dom

[unikitty37]

Add instructions on how to configure Vitest to import @testing-library/jest-dom automatically, to match the Vite instructions at 6.2.

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[timdeschryver]

Thanks for this addition to the docs.
What do you think of adding this under a 5.3 bullet point?

[unikitty37]

Yes, that's a good idea.

[eps1lon]

Why would you use a library specifically for Jest in Vitest? We already have an assertion library specifically for Vitest called vitest-dom. Could we clarify first if the folks at @testing-library/jest-dom want to support Vitest in addition to Jest?

[unikitty37]

Why would you use a library specifically for Jest in Vitest? We already have an assertion library specifically for Vitest called vitest-dom. Could we clarify first if the folks at @testing-library/jest-dom want to support Vitest in addition to Jest?

I was just updating the current documentation, which uses jest-dom. I didn't even know about vitest-dom — but it doesn't seem to be compatible with the current vitest version:

╰─▷ npm i -D vitest-dom npm ERR! code ERESOLVE npm ERR! ERESOLVE unable to resolve dependency tree npm ERR! npm ERR! While resolving: frontend@0.0.1 npm ERR! Found: vitest@0.25.8 npm ERR! node_modules/vitest npm ERR! dev vitest@"~0.25.3" from the root project npm ERR! npm ERR! Could not resolve dependency: npm ERR! peer vitest@"^0.16.0" from vitest-dom@0.0.4 npm ERR! node_modules/vitest-dom npm ERR! dev vitest-dom@"*" from the root project 

[unikitty37]

Since vitest-dom doesn't work with current vitest, and my comment pointing this out doesn't seem to have resulted in any response, I'm going to assume this contribution is unwanted at this point.