Prepare the plugin for flat config

[Belco90]

Plugin version

n/a

What problem do you want to solve?

• Prepare the plugin for flat config.

Your take on the correct solution?

Apply the changes mentioned in the linked migration docs so the plugin is compatible with flat config mechanism

Anything else?

No response

Do you want to submit a pull request to implement this change?

Yes

[Belco90]

Adding backwards compatibility is a bit painful, so I'll implement the ESLint v9 compatibility changes as part of the next major version of the plugin.

[studioswong]

Hello, @Belco90, thank you for setting this up as I can envision this being a pressing issue as more and more of us start to look into migrating to ESLint v9 and changing to use flat config.

While the related changes for compatibility for ESLint v9 are being implemented, are there any way for us to specify using the eslint-plugin-testing-library as a plugin in flat config ?( I am still on ESLint v8.57 so technically should still be able to use the testing library plugin, just that we have migrated to use flat config in preparation for the migration)

I have tried the typical way of importing the library and specifying it as a plugin under plugins, as per recommendations for the migration guide, but unfortunately it doesn't work. Not sure if there is a specific way that I should specify the plugin? ( such as specifying it diirectly in the config array like how we usually use for extends in the old config setup?)

Thank you!

[Belco90]

Hey @studioswong! I don't think there is a way to make the plugin compatible with ESLint v9 until we released the corresponding changes, so I'm afraid you'll have to wait until the next version of the plugin.

I'm working on it already, you can follow the progress here: https://github.com/orgs/testing-library/projects/19

edit:

To make it clear, you can use the plugin with ESLint v9 if not using the new flat config. Otherwise, this ticket must be addressed for flat config compatibility.

[studioswong]

Thank you so much for your speedy reply @Belco90 ! Gotcha - So basically it's all down to flat config and not ESLint v9 😄

Really looking forward to your work with the support for flat configs - I'm sure a lot of users will come across this soon in the coming weeks! and thanks so much for the great work with this plugin!

[Belco90]

Adding backwards compatibility is a bit painful, so I'll implement the ESLint v9 compatibility changes as part of the next major version of the plugin.

Finally keeping backwards compatibility with RC config, but those configs will be renamed with a -legacy suffix so this will be a breaking change anyway.