Deno support

[kirillgroshkov]

Sorry, https://twitter.com/kentcdodds/status/1260716918526242816
:)

[kentcdodds]

Booo! 😆

lol, but in all seriousness, I'd be curious to know what it takes to support Deno, but I don't think we need an issue open about this as it's not a priority until someone could reasonably make JSDOM (or similar) work in Deno, so I'm going to close this.

[YOU54F]

Hey @kentcdodds ,

I've started messing about with deno & react, using aleph.js and wanted to look at using react-testing-library or a deno equivalent, and stumbled across this.

We can use JSDOM in deno, example here

https://github.com/YOU54F/deno-examples/blob/main/jsdom/jsdom.test.ts

Only started using deno yesterday, out of curiosity to build an express like provider, and react based consumer equiv and exploring the available testing tools.

[kigiri]

You could also check https://github.com/b-fuze/deno-dom in a similar style, a more deno native lib.
Since deno handle JSX out of the box now, it could be a pretty nice DX to test react code without having to install and config anything, just deno run and your tests run

[Industrial]

Hello.

Libraries like JSDOM are working in Deno.

I am trying to get testing-library to work and keep getting the error:

error: TypeError: For queries bound to document.body a global document has to be available... Learn more: https://testing-library.com/s/screen-global-error
    at Object.helpers.<computed> [as queryByText] (https://esm.sh/v92/@testing-library/[email protected]/deno/dom.development.js:2365:11)
    at file:///home/tom/Code/code9/deno/test-fresh/components/Container.test.tsx:32:17

I have tried deno-dom-wasm, deno_dom, and jsdom but when I do:

  globalThis.document = document;
  globalThis.window.document = document;

I keep getting that error.

I'm not sure how to patch it correctly, since Deno provides a globalThis.window environment and it is readonly.

When using

import 'npm:global-jsdom/register'

But that throws the error:

error: TypeError: Cannot assign to read only property 'window' of object '#<Window>'

The DOM libraries are working by themselves. They just can't be put on the global object easily.

Maybe there can be a way to configure/pass the document object to testing-library? That would make it easy to swap the DOM library.

[Industrial]

@kentcdodds Can we open this ticket again? Being able to do proper component tests will make Deno a much more reliable platform for doing React apps.

Would be great if the https://github.com/denoland/fresh starter would include some component tests as an example and used react-testing-library.

[kentcdodds]

If someone wants to work on that it's great by me! I don't have the bandwidth to work on it personally. As far as I'm aware, nothing has changed since my last comment on this so I don't see a reason to reopen 🤷‍♂️

[john-griffin]

I was eventually able to get this working but it's very messy, summarized here https://github.com/john-griffin/deno-dom-test