Preserve hook output order with a shared pipe - #2385
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📦 Cargo Bloat ComparisonBinary size change: -0.34% (29.2 MiB → 29.1 MiB) Expand for cargo-bloat outputHead Branch ResultsBase Branch Results |
⚡️ Hyperfine BenchmarksSummary: 0 regressions, 1 improvements above the 10% threshold. Environment
CLI CommandsBenchmarking basic commands in the main repo:
|
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base --version |
2.3 ± 0.1 | 2.2 | 2.6 | 1.08 ± 0.04 |
prek-head --version |
2.1 ± 0.1 | 2.0 | 2.5 | 1.00 |
prek list
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base list |
9.3 ± 0.1 | 9.1 | 9.8 | 1.03 ± 0.02 |
prek-head list |
9.1 ± 0.1 | 8.9 | 9.5 | 1.00 |
prek validate-config .pre-commit-config.yaml
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base validate-config .pre-commit-config.yaml |
3.3 ± 0.1 | 3.2 | 3.5 | 1.09 ± 0.03 |
prek-head validate-config .pre-commit-config.yaml |
3.0 ± 0.1 | 2.9 | 3.2 | 1.00 |
prek sample-config
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base sample-config |
2.6 ± 0.1 | 2.5 | 2.7 | 1.05 ± 0.03 |
prek-head sample-config |
2.5 ± 0.1 | 2.3 | 2.6 | 1.00 |
Cold vs Warm Runs
Comparing first run (cold) vs subsequent runs (warm cache):
prek run --all-files (cold - no cache)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run --all-files |
74.7 ± 2.6 | 71.0 | 79.3 | 1.03 ± 0.04 |
prek-head run --all-files |
72.5 ± 1.9 | 70.1 | 74.8 | 1.00 |
prek run --all-files (warm - with cache)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run --all-files |
72.9 ± 2.5 | 69.3 | 76.6 | 1.02 ± 0.05 |
prek-head run --all-files |
71.9 ± 2.3 | 68.7 | 76.3 | 1.00 |
Full Hook Suite
Running the builtin hook suite on the benchmark workspace:
prek run --all-files (full builtin hook suite)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run --all-files |
72.7 ± 2.4 | 67.7 | 79.4 | 1.00 |
prek-head run --all-files |
73.4 ± 6.3 | 68.6 | 114.3 | 1.01 ± 0.09 |
Individual Hook Performance
Benchmarking each hook individually on the test repo:
prek run trailing-whitespace --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run trailing-whitespace --all-files |
19.4 ± 0.5 | 18.8 | 20.6 | 1.00 ± 0.04 |
prek-head run trailing-whitespace --all-files |
19.3 ± 0.5 | 18.5 | 20.8 | 1.00 |
prek run end-of-file-fixer --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run end-of-file-fixer --all-files |
24.9 ± 1.6 | 22.9 | 28.0 | 1.01 ± 0.09 |
prek-head run end-of-file-fixer --all-files |
24.6 ± 1.7 | 22.8 | 28.2 | 1.00 |
prek run check-json --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run check-json --all-files |
7.8 ± 0.3 | 7.2 | 8.5 | 1.03 ± 0.06 |
prek-head run check-json --all-files |
7.6 ± 0.3 | 7.0 | 8.2 | 1.00 |
prek run check-yaml --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run check-yaml --all-files |
7.6 ± 0.1 | 7.4 | 7.9 | 1.02 ± 0.03 |
prek-head run check-yaml --all-files |
7.4 ± 0.2 | 7.2 | 7.9 | 1.00 |
prek run check-toml --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run check-toml --all-files |
7.7 ± 0.3 | 7.4 | 8.5 | 1.02 ± 0.05 |
prek-head run check-toml --all-files |
7.6 ± 0.3 | 7.1 | 8.3 | 1.00 |
prek run check-xml --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run check-xml --all-files |
7.6 ± 0.4 | 7.2 | 8.8 | 1.02 ± 0.08 |
prek-head run check-xml --all-files |
7.4 ± 0.4 | 7.0 | 8.5 | 1.00 |
prek run detect-private-key --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run detect-private-key --all-files |
13.4 ± 1.0 | 11.7 | 15.3 | 1.03 ± 0.11 |
prek-head run detect-private-key --all-files |
13.1 ± 1.0 | 12.0 | 15.7 | 1.00 |
prek run fix-byte-order-marker --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run fix-byte-order-marker --all-files |
17.5 ± 0.7 | 16.6 | 19.2 | 1.01 ± 0.06 |
prek-head run fix-byte-order-marker --all-files |
17.3 ± 0.7 | 16.0 | 18.6 | 1.00 |
Installation Performance
Benchmarking hook installation (fast path hooks skip Python setup):
prek install-hooks (cold - no cache)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base install-hooks |
4.6 ± 0.2 | 4.5 | 5.0 | 1.06 ± 0.05 |
prek-head install-hooks |
4.4 ± 0.0 | 4.3 | 4.4 | 1.00 |
prek install-hooks (warm - with cache)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base install-hooks |
4.6 ± 0.0 | 4.6 | 4.6 | 1.05 ± 0.01 |
prek-head install-hooks |
4.4 ± 0.1 | 4.3 | 4.5 | 1.00 |
File Filtering/Scoping Performance
Testing different file selection modes:
prek run (staged files only)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run |
36.6 ± 0.7 | 35.4 | 38.0 | 1.00 |
prek-head run |
37.1 ± 1.1 | 35.5 | 38.7 | 1.01 ± 0.04 |
prek run --files '*.json' (specific file type)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run --files '*.json' |
8.0 ± 0.1 | 7.8 | 8.2 | 1.02 ± 0.02 |
prek-head run --files '*.json' |
7.8 ± 0.1 | 7.6 | 8.1 | 1.00 |
Workspace Discovery & Initialization
Benchmarking hook discovery and initialization overhead:
prek run --dry-run --all-files (measures init overhead)
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run --dry-run --all-files |
7.2 ± 0.2 | 6.8 | 7.7 | 1.08 ± 0.04 |
prek-head run --dry-run --all-files |
6.7 ± 0.1 | 6.5 | 7.0 | 1.00 |
Meta Hooks Performance
Benchmarking meta hooks separately:
prek run check-hooks-apply --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run check-hooks-apply --all-files |
12.0 ± 0.2 | 11.8 | 12.4 | 1.08 ± 0.08 |
prek-head run check-hooks-apply --all-files |
11.1 ± 0.8 | 10.2 | 12.2 | 1.00 |
prek run check-useless-excludes --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run check-useless-excludes --all-files |
10.7 ± 0.1 | 10.6 | 10.9 | 1.02 ± 0.02 |
prek-head run check-useless-excludes --all-files |
10.5 ± 0.1 | 10.3 | 10.7 | 1.00 |
prek run identity --all-files
| Command | Mean [ms] | Min [ms] | Max [ms] | Relative |
|---|---|---|---|---|
prek-base run identity --all-files |
38.2 ± 90.5 | 9.9 | 358.9 | 3.81 ± 9.03 |
prek-head run identity --all-files |
10.0 ± 0.5 | 9.6 | 11.1 | 1.00 |
✅ Performance improvement for prek run identity --all-files: 73.7900% faster
Suppress Gitleaks banner and status logs in the Docker image test so Docker's stdout/stderr interleaving cannot make the snapshot flaky after #2385.
Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## master #2385 +/- ##
=========================================
Coverage ? 93.37%
=========================================
Files ? 129
Lines ? 27513
Branches ? 0
=========================================
Hits ? 25689
Misses ? 1824
Partials ? 0 ☔ View full report in Codecov by Harness. 🚀 New features to boost your workflow:
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This MR contains the following updates: | Package | Type | Update | Change | |---|---|---|---| | [prek](https://github.com/j178/prek) | tools | patch | `0.4.10` → `0.4.13` | MR created with the help of [el-capitano/tools/renovate-bot](https://gitlab.com/el-capitano/tools/renovate-bot). **Proposed changes to behavior should be submitted there as MRs.** --- ### Release Notes <details> <summary>j178/prek (prek)</summary> ### [`v0.4.13`](https://github.com/j178/prek/blob/HEAD/CHANGELOG.md#0413) [Compare Source](j178/prek@v0.4.12...v0.4.13) Released on 2026-08-10. ##### Highlights ##### Manage hook tools with mise The new `language: mise` support lets hooks install tools using [`mise`](https://mise.jdx.dev/) in an isolated environment: ```yaml repos: - repo: local hooks: - id: golangci-lint name: golangci-lint language: mise additional_dependencies: ["aqua:golangci/golangci-lint@2"] entry: golangci-lint run --fast-only ./... pass_filenames: false ``` ##### Run commands in hook environments The new `prek exec` subcommand can run an explicit command in a configured hook's prepared environment. For example, the hook above makes its managed binary available to this command: ```console $ prek exec golangci-lint -- golangci-lint --version ``` ##### Enhancements - Add `mise` language support ([#​2540](j178/prek#2540)) - Add `deny-filename-pattern` and `require-filename-pattern` hooks ([#​2488](j178/prek#2488)) - Add `prek exec` for running commands in a hook environment ([#​2478](j178/prek#2478)) - Add `yaml-language-server:` comment to YAML sample config ([#​2486](j178/prek#2486)) - Make `prek cache size` output terminal-aware ([#​2508](j178/prek#2508)) - Match file regexes against path bytes ([#​2541](j178/prek#2541)) - Show hook aliases in run output ([#​2497](j178/prek#2497)) - Show hook descriptions in run output ([#​2490](j178/prek#2490)) ##### Performance - Avoid env cache scans for skipped hooks ([#​2502](j178/prek#2502)) - Cache Node version queries ([#​2500](j178/prek#2500)) ##### Bug fixes - Fix Node hook installation with npm 11 ([#​2487](j178/prek#2487)) - Isolate dependency installs from inherited Git repository state ([#​2506](j178/prek#2506)) ##### Documentation - Document combined group filtering ([#​2495](j178/prek#2495)) - Explain what prek does in README ([#​2507](j178/prek#2507)) - Refresh "Why prek" highlights ([#​2474](j178/prek#2474)) ##### Contributors - [@​will-wright-eng](https://github.com/will-wright-eng) - [@​Repiteo](https://github.com/Repiteo) - [@​j178](https://github.com/j178) ### [`v0.4.12`](https://github.com/j178/prek/blob/HEAD/CHANGELOG.md#0412) [Compare Source](j178/prek@v0.4.11...v0.4.12) Released on 2026-08-03. ##### Enhancements - Add `--require-group` for hook group intersections ([#​2472](j178/prek#2472)) - Align fast-path and builtin pre-commit hooks ([#​2433](j178/prek#2433)) - Do not shuffle file list for verbose output ([#​2431](j178/prek#2431)) - Improve top-level command descriptions ([#​2429](j178/prek#2429)) - Install `uv` from Astral CDN and drop source racing ([#​2455](j178/prek#2455)) - Make `prek install --force` bypass external hooks paths ([#​2437](j178/prek#2437)) - Show builtin hook flags in verbose list output ([#​2427](j178/prek#2427)) - Verify uv release archive checksums ([#​2456](j178/prek#2456)) ##### Performance - Precompute file tags in parallel ([#​2440](j178/prek#2440)) - Skip diffs after known hook modifications ([#​2447](j178/prek#2447)) - Skip worktree diffs for read-only languages ([#​2432](j178/prek#2432)) - Track builtin hook file changes directly ([#​2404](j178/prek#2404)) ##### Bug fixes - Use full object IDs in diff snapshots ([#​2448](j178/prek#2448)) ##### Documentation - Add a multi-repository configuration example ([#​2434](j178/prek#2434)) - Rewrite benchmark documentation ([#​2469](j178/prek#2469)) ##### Contributors - [@​j178](https://github.com/j178) - [@​BitWeaverDev](https://github.com/BitWeaverDev) - [@​allanlewis](https://github.com/allanlewis) ### [`v0.4.11`](https://github.com/j178/prek/blob/HEAD/CHANGELOG.md#0411) [Compare Source](j178/prek@v0.4.10...v0.4.11) Released on 2026-07-25. ##### Highlights - This release adds two new builtin hooks, `deny-pattern` and `require-pattern`, as native alternatives for `pygrep` use cases. `deny-pattern` fails when a configured pattern is found, while `require-pattern` ensures every selected file contains a match. By matching natively without spawning a Python subprocess, they run over 4x faster than `pygrep` in benchmarks. Note that they use [Rust `regex` syntax](https://docs.rs/regex/latest/regex/#syntax), which does not support look-around features such as negative lookbehind. - `prek run` now supports `--glob <PATTERN>` to run hooks on tracked files matching a glob. It can be repeated or combined with `--files` and `--directory`. - Hook priorities now support reusable aliases: ```toml [priorities] checks = 10 [[repos]] repo = "builtin" hooks = [ { id = "check-json", priority = "checks" }, { id = "check-yaml", priority = "checks" }, ] ``` This makes parallel scheduling easier to read and maintain. ##### Enhancements - Add `deny-pattern` and `require-pattern` builtin hooks ([#​2359](j178/prek#2359)) - Support `--glob` patterns in `prek run` ([#​2381](j178/prek#2381)) - Support reusable aliases for hook priorities ([#​2331](j178/prek#2331)) - Implement `requirements-txt-fixer` as a builtin hook ([#​2390](j178/prek#2390)) - Improve user-facing warnings and errors ([#​2380](j178/prek#2380)) - Install Node hooks through git url ([#​2394](j178/prek#2394)) ##### Performance - Reduce blocking-pool overhead in file hooks ([#​2384](j178/prek#2384)) - Speed up mixed-line-ending scans with memchr2 ([#​2391](j178/prek#2391)) ##### Bug fixes - Honor filenames in builtin hook entry and args ([#​2389](j178/prek#2389)) - Match identify tags across filename parts ([#​2399](j178/prek#2399)) - Preserve hook output order with a shared pipe ([#​2385](j178/prek#2385)) - Preserve system download policy when applying metadata ([#​2395](j178/prek#2395)) ##### Contributors - [@​j178](https://github.com/j178) - [@​chrisoro](https://github.com/chrisoro) </details> --- ### Configuration 📅 **Schedule**: (UTC) - Branch creation - At any time (no schedule defined) - Automerge - At any time (no schedule defined) 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this MR and you won't be reminded about this update again. --- - [ ] <!-- rebase-check -->If you want to rebase/retry this MR, check this box --- This MR has been generated by [Mend Renovate](https://github.com/renovatebot/renovate). <!--renovate-debug:eyJjcmVhdGVkSW5WZXIiOiI0My4yODYuMSIsInVwZGF0ZWRJblZlciI6IjQzLjI4OC4wIiwidGFyZ2V0QnJhbmNoIjoibWFpbiIsImxhYmVscyI6WyJSZW5vdmF0ZSBCb3QiLCJhdXRvbWF0aW9uOmJvdC1hdXRob3JlZCIsImRlcGVuZGVuY3ktdHlwZTo6cGF0Y2giXX0=-->
Fix hook output ordering by capturing stdout and stderr through a shared pipe before spawning the process. Centralize merged batch output handling across language backends.
Closes #2382