Repository navigation
Speed up parse ~15% by reusing the last line in Input#fromOffset - #2173
deadstrobe5 wants to merge 1 commit into
Conversation
|
No actionable comments were generated in the recent review. 🎉 ℹ️ Recent review info
📝 Walkthrough
Merge Risk: ⚪ Minimal · up to
|
| Check name | Status | Explanation | Resolution |
|---|---|---|---|
| Docstring Coverage |  |
Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 1 files. | Write docstrings for the functions missing them to satisfy the coverage threshold. |
-
Check name Status Explanation Description Check Check skipped - CodeRabbit’s high-level summary is enabled. Title check The title clearly and concisely describes the main performance change: reusing the last line in Input#fromOffset to speed up parsing. Linked Issues check Check skipped because no linked issues were found for this pull request. Out of Scope Changes check Check skipped because no linked issues were found for this pull request.
- Fix all pre-merge checks with AI
✨ Finishing Touches
-
🧪 Generate unit tests (beta)
-
- Create a new PR
-
- Autofix · Keep fixing CodeRabbit findings and required CI, and resolving merge conflicts
Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.
Comment @coderabbitai help to get the list of available commands.
|
Cool. My favorite type of PR. But we are making 9.0 release right now. I think we will release it there. |
|
Thanks! Shipping it with 9.0 sounds great. |
Input#fromOffset()did a binary search over all line starts on every call, andgetLineToIndex()built the table withcss.split('\n'), allocating a string per line. The parser asks for positions in increasing order, so the answer is almost always the line from the previous call or the next one (on bootstrap.css: 11,098 same line, 9,849 next line, 1,060 other). This checks those two lines first, falls back to the binary search otherwise, and builds the line table with anindexOfloop.postcss.parse(bootstrap.css).toString(), the "PostCSS" case from postcss/benchmark, on current Bootstrapdist/css/bootstrap.css(496 KB), Node 26.3, Apple M5. 7 alternating processes per side, each the median of 40 runs after 30 warmup:That is about 15% less time per parse.
bootstrap.min.css(one long line) shows no measurable change either way.Output is identical to main (AST JSON with positions, CSS and inline source maps) on bootstrap.css and all 30 postcss-parser-tests cases, and
fromOffsetmatches main on 62,000 random offsets queried in random order.pnpm unit, eslint, check-dts and size-limit pass.Summary by CodeRabbit