Reduce binary size of bundled caniuse/electron data#688
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Re-represent the embedded data tables so the existing deflate compresses them better and the generated rodata carries no string relocations. All changes are lossless: query results are byte-identical to before (verified across every region/feature/electron/cover query), tests and proptests pass. - Delta-encode region usage percentages (non-increasing per region, so the deltas are small with long zero runs) - Intern region (browser, version) pairs into one popularity-ordered table and store a u16 pair-index per datum, dropping the redundant per-region browser-id array (only ~557 unique pairs were stored ~47k times) - Intern feature-support version strings via a sorted table + u16 indices - Move region/feature lookup keys out of inline &[&str] into deflate blobs decoded once (no fat pointers / relocations) - String-pack the global-usage and electron tables: a concatenated &str pool referenced by a u32 bitpacking offset<<8|len, eliminating the per-entry &str relocations Linux (x86_64-unknown-linux-musl): 861,760 -> 784,128 bytes (-9.0%).
Codecov Report✅ All modified and coverable lines are covered by tests. Additional details and impacted files@@ Coverage Diff @@
## main #688 +/- ##
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+ Coverage 99.03% 99.04% +0.01%
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Files 47 47
Lines 2374 2411 +37
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+ Hits 2351 2388 +37
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Decode each string lookup table (the region and feature version tables and the generated region/feature key tables) into a single OnceLock<Vec<String>> instead of the previous two-OnceLock "decompressed bytes + borrowing Vec<&str>" pair; .as_str() still hands the call sites the &'static str they need. Inline include_bytes! so each compressed blob needs only one static. Plain std::sync::OnceLock throughout, no helper types. No behavior change (query results stay byte-identical; verified across the full region/feature/ electron/cover query space).
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## 🤖 New release * `oxc-browserslist`: 3.0.3 -> 3.0.4 (✓ API compatible changes) <details><summary><i><b>Changelog</b></i></summary><p> <blockquote> ## [3.0.4](oxc-browserslist-v3.0.3...oxc-browserslist-v3.0.4) - 2026-05-29 ### Other - DRY up feature/region codegen with shared table + lookup helpers ([#694](#694)) - Consolidate bundled-data loading behind compression helpers ([#693](#693)) - Reduce binary size: run-length encode feature support versions ([#692](#692)) - Reduce binary size: Zopfli codegen compression + percentage byte-plane ([#691](#691)) - Reduce binary size: byte-plane (stream-split) compression for region pair indices ([#690](#690)) - Update README binary size to 621K ([#689](#689)) - Reduce binary size of bundled caniuse/electron data ([#688](#688)) - Switch codegen data source from caniuse-db to caniuse-lite ([#687](#687)) - Update browserslist ([#685](#685)) - Update rust crates ([#682](#682)) - Update browserslist ([#679](#679)) - Update browserslist ([#678](#678)) - Update browserslist ([#677](#677)) - Update browserslist ([#673](#673)) - Update browserslist ([#671](#671)) </blockquote> </p></details> --- This PR was generated with [release-plz](https://github.com/release-plz/release-plz/). Co-authored-by: oxc-guard[bot] <276638029+oxc-guard[bot]@users.noreply.github.com>
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Reduces the footprint that this crate's bundled Can I Use / Electron / Node data adds to a binary, by re-representing the embedded tables so the existing deflate compresses them better and the generated
rodatacarries no string relocations. No new dependencies, no profile changes, and no loss of precision — query results are byte-identical to before (verified across the full region / feature / electron / cover query space, plus the existing test suite and JS-reference proptests).Size
Measured with the
inspectexample:x86_64-unknown-linux-muslaarch64-apple-darwin)The Linux figure is the more representative one: on ELF every
&strin a static table costs a 24-byte.rela.dynrelocation on top of its 16-byte fat pointer, so removing those (see the last two techniques) pays off most there.Techniques
All are lossless and operate on the generated data representation (
xtaskcodegen) together with the matching runtime decoders:prev − curryields small deltas with long runs of zeros that deflate packs tightly.u16pair-index per entry instead of a browser byte and a version index — dropping the redundant per-region browser array.y/asupport lists referenced the same version strings over and over; they're nowu16indices into a sorted version table.&[&str](a 16-byte fat pointer plus a relocation per entry); they're now deflate blobs decoded once.&stris replaced by au32that bitpacksoffset << 8 | leninto a single concatenated string pool, eliminating the per-entry&strrelocations with no decode code.Decoding stays plain
std::sync::OnceLock, with no helper types.🤖 Generated with Claude Code