Replace outdated Prettier settings with recommended ones

[gaearon]

Summary:

The React Native ESLint preset currently endorses the Prettier integration that is explicitly recommended against by Pretier itself. Notice the difference between these two packages:

• eslint-config-prettier is the config that turns off all formatting rules. It's recommended by Prettier to be used together with Prettier. You'd still use Prettier itself to actually do the formatting.
• eslint-plugin-prettier is a legacy plugin developed a long time ago and that predates most modern Prettier integrations. It runs Prettier as if it were an ESLint rule, applies formatting on --fix, and is not recommended.

Unfortunately, RN uses the latter one (and always has).

This PR removes eslint-plugin-prettier and instead enables eslint-config-prettier, as recommended by Prettier.

As a consequence, you'll no longer see squiggly lines in your editor for stuff that isn't actually errors:

As another consequence, you'll have to set up your own Prettier step in your pipeline.

For example, if your precommit hook only contained eslint --fix, you'll now also need to run prettier --write there as well. Similarly, if you want Prettier to fail CI, you'd need to find where you call eslint and also do prettier --check there.

Here's an example for how to do it: bluesky-social/social-app#3373

Changelog:

[GENERAL] [BREAKING] - RN ESLint config no longer runs Prettier during ESLint

Test Plan:

Tested locally, verified formatting changes no longer get flagged as violations by the RN config.

[berdyshev]

duplicate of #41877?

[facebook-github-bot]

@yungsters has imported this pull request. If you are a Meta employee, you can view this diff on Phabricator.

[lydell]

https://github.com/prettier/eslint-config-prettier/blob/5687e7de69ac132f053b4bc5474d5963aa3bf6d6/README.md#L7

Note that this config only turns rules off, so it only makes sense using it together with some other config.

Suggested change

extends: ['prettier'],

[gaearon]

I suspect that people probably rely on it being turned off. So without this, the upgrade path might be too annoying / non-obvious. I think we can remove it separately later.

[lydell]

It feels like I’m missing something. In what situation does it help to have extends: ['prettier'] here? Remember that rules win over extends.

[yungsters]

The assumption is that developers are using this along with recommended configs (e.g. the ones included with ESLint), so this would disable those rules.

If someone has a project in which they explicitly enable rules that are disabled by eslint-config-prettier, then yes… this would not overrule that.

[facebook-github-bot]

@yungsters merged this pull request in 727f30b.

[github-actions]

This pull request was successfully merged by @gaearon in 727f30b.

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