Configure Jest dynamically per side

[RobertBroersma]

👋

This works, but only by circumventing an alleged bug in Jest.

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A simpler way to do this would be to require the user to define a jest.config file for every side that they create. This could be generated by create-redwood-app or by yarn rw generate side (or w/e @peterp has in store for us!). This way the main config for the test command can be simplified to just pick up any project (jest.config) inside of the user's monorepo.

The file contents could be defaulted to something like

const { createBrowserJestConfig } = require('@redwoodjs/core')

module.exports = createBrowserJestConfig()

Upsides to this simpler approach:

• No Jest overrides
• The generated jest.config files provide an excellent entry point for extending configs.
• In the current setup of this PR, it does work out of the box in current RW projects and future projects, but it's highly likely (assumption) that most users will want to extend their Jest config at some point. So they'll have Jest Configs in their project anyway. We would then be supporting 2 approaches, only to avoid requiring config files for existing RW apps.

The biggest downside to that would be that existing projects would have to add these configs manually.

@peterp @thedavidprice @ others, what do you think? Typing this all out pretty much convinced myself the simpler approach is better, but I'd love to hear what you think 😄

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Benefits:

• Nice colors in CLI.
• Run watch simultaneously over every Side.
• Full coverage for all your code in one place.
• Use watch plugins globally (future stuff).

TODO Before merge:

• Decide approach.
• Expose Jest side configs for extending.
• Dynamically add colors for different sides.

[Tobbe]

I prefer the simpler approach as well. And I wonder, could we make yarn rw upgrade add default jest.config files if they don't exist?

[RobertBroersma]

@Tobbe Oooh that sounds like a good idea!

[peterp]

@RobertBroersma I like your idea of adding the configuration file to a project; and I really like the way that you've got a function to grab that config, what do you think of making it more generic?

const { getConfig }  = require('@redwoodjs/core')
module.exports = getConfig({ type: 'jest', target: 'browser' })

[RobertBroersma]

I think that's a good idea, @peterp !

[RobertBroersma]

I've updated this with the simpler approach as discussed!

Check this repo for the jest.config.js's (In the web and api folders): https://github.com/RobertBroersma/redwood-testing
(I think it's been mentioned before, but it might be nice to have some testing repo inside the monorepo to see the changes alongside potential changes required in apps + for testing!)

Does this getConfig kind of fit what you had in mind, @peterp ?

I'll do a short writeup of some assumptions/default config I did in the config functions and in the test command later!

[peterp]

I'm really struggling to see the value versus the complexity introduce via this PR.

[RobertBroersma]

I'm really struggling to see the value versus the complexity introduce via this PR.

Can you elaborate on what you find more complex in this situation? In my mind I just moved a few things around and made it less complex! Perhaps I can shine light on some stuff or maybe I'm in too deep.

[peterp]

@RobertBroersma The stuff related to the type of VCS you're using really threw me off, I'll take another look with some fresh eyes in the morning.

[peterp]

It looks good to me! We just need to confirm that the changes to using the absolute paths for the main babel src alias isn't breaking deployments. (I left a note.)

[RobertBroersma]

It looks good to me! We just need to confirm that the changes to using the absolute paths for the main babel src alias isn't breaking deployments. (I left a note.)

My bad! Can be removed. Thought I did.

[Tobbe]

I've been reading about paths, which always gets my windows spidey senses tingling... Want me to test-run anything on win?

[RobertBroersma]

@Tobbe If you can run yarn rw test with this little test repo: https://github.com/RobertBroersma/redwood-testing to confirm that would be magnificent!