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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>