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## Summary
Hi guys, thanks for you great work!
I work on performance improvements on
https://github.com/schoero/eslint-plugin-better-tailwindcss project.
Part of issues can be fixed on the tailwind side only.
This is a first fix, I have a bigger one in mind, it would require a
small additional public API method - out of scope of this PR.
Please let me know what you think.
## Finding
`getVariantOrder()` re-sorts all parsed variants with the (expensive)
variant comparator on every call, and it is called by every
compileCandidates() invocation — per build pass, per @apply
substitution, and hundreds of times during candidate canonicalization
via the variant signature caches. Since parsedVariants is append-only,
the computed order only changes when a new variant is parsed, so we can
cache the result and invalidate on parsedVariants.size. This makes cold
canonicalization (IntelliSense, lint plugins) faster and removes
repeated sorting from @apply substitution and incremental rebuilds.
## Test plan
Tested at https://github.com/smnbbrv/better-tailwindcss-bench . The
relevant part is the `epbt-now / tw-patched`
**plugin cost** (ms, cold run net of parse baseline)
| codebase | epbt-now / tw-now | epbt-patched / tw-now | epbt-now /
tw-patched | epbt-patched / tw-patched |
| ---------- | ----------------: | --------------------: |
--------------------: | ------------------------: |
| mixed | 6292 | 3965 (-37%) | 5395 (-14%) | 3595 (-43%) |
| repetitive | 5279 | 2425 (-54%) | 4819 (-9%) | 2124 (-60%) |
| unique | 6096 | 5458 (-10%) | 5507 (-10%) | 5295 (-13%) |
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