Philipp Spiess ab9e2b716b
Support complex addUtilities() configs (#15029)
This PR adds support for complex `addUtilities()` configuration objects
that use child combinators and other features.

For example, in v3 it was possible to add a utility that changes the
behavior of all children of the utility class node by doing something
like this:

```ts
addUtilities({
  '.red-children > *': {
    color: 'red',
  },
});
```

This is a pattern that was used by first-party plugins like
`@tailwindcss/aspect-ratio` but that we never made working in v4, since
it requires parsing the selector and properly extracting all utility
candidates.

While working on the codemod that can transform `@layer utilities`
scoped declarations like the above, we found out a pretty neat
heuristics on how to migrate these cases. We're basically finding all
class selectors and replace them with `&`. Then we create a nested CSS
structure like this:

```css
.red-children {
  & > * {
    color: red;
  }
}
```

Due to first party support for nesting, this works as expected in v4.

## Test Plan

We added unit tests to ensure the rewriting works in some edge cases.
Furthermore we added an integration test running the
`@tailwindcss/aspect-ratio` plugin. We've also installed the tarballs in
the Remix example from the
[playgrounds](https://github.com/philipp-spiess/tailwindcss-playgrounds)
and ensure we can use the `@tailwindcss/aspect-ratio` plugin just like
we could in v3:
 
<img width="2560" alt="Screenshot 2024-11-18 at 13 44 52"
src="https://github.com/user-attachments/assets/31889131-fad0-4c37-b574-cfac2b99f786">

---------

Co-authored-by: Robin Malfait <malfait.robin@gmail.com>
Co-authored-by: Jordan Pittman <jordan@cryptica.me>
2024-11-19 15:52:06 +01:00
..
2024-11-07 16:48:49 +01:00