tailwindcss

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History

Improve performance of upgrade tool (#18068 )

This PR improves the performance of the upgrade tool due to a regression
introduced by https://github.com/tailwindlabs/tailwindcss/pull/18057

Essentially, we had to make sure that we are not in `<style>…</style>`
tags because we don't want to migrate declarations in there such as
`flex-shrink: 0;`

The issue with this approach is that we checked _before_ the candidate
if a `<style` cold be found and if we found an `</style>` tag after the
candidate.

We would basically do this check for every candidate that matches.

Running this on our Tailwind UI codebase, this resulted in a bit of a
slowdown:

```diff
- Before: ~13s
+  After: ~5m 39s
```

... quite the difference.

This is because we have a snapshot file that contains ~650k lines of
code. Looking for `<style>` and `</style>` tags in a file that large is
expensive, especially if we do it a lot.

I ran some numbers and that file contains ~1.8 million candidates.

Anyway, this PR fixes that by doing a few things:

1. We will compute the `<style>` and `</style>` tag positions only once
per file and cache it. This allows us to re-use this work for every
candidate that needs it.
2. We track the positions, which means that we can simply check if a
candidate's location is within any of 2 start and end tags. If so, we
skip it.

Running the numbers now gets us to:

```diff
- Before: ~5m 39s
+  After: ~9s
```

Much better!

---------

Co-authored-by: Jordan Pittman <jordan@cryptica.me>

2025-05-19 10:41:40 -04:00

src

Improve performance of upgrade tool (#18068 )

2025-05-19 10:41:40 -04:00

package.json

Prepare v4.1.7 release (#18040 )

2025-05-15 15:31:18 +02:00

README.md

Add initial codemod tooling (#14434 )

2024-09-18 16:45:43 +02:00

tsconfig.json

Internal refactor, introduce AtRule (#14802 )