Add check-json5 as builtin hooks by j178 · Pull Request #1367 · j178/prek

j178 · 2026-01-16T05:57:59Z

Closes #823

github-actions · 2026-01-16T06:01:05Z

📦 Cargo Bloat Comparison

Binary size change: +0.00% (22.3 MiB → 22.3 MiB)

Expand for cargo-bloat output

Head Branch Results

 File  .text    Size        Crate Name
 0.3%   0.8% 72.3KiB        prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.2%   0.6% 54.7KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 49.9KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 46.8KiB         prek prek::run::{{closure}}
 0.2%   0.5% 42.4KiB         prek prek::cli::run::run::run::{{closure}}
 0.2%   0.4% 35.0KiB         prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.1%   0.3% 31.9KiB        prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.1%   0.3% 29.2KiB  serde_json? <&mut serde_json::de::Deserializer<R> as serde_core::de::Deserializer>::deserialize_struct
 0.1%   0.3% 27.6KiB         prek prek::identify::by_extension::{{closure}}
 0.1%   0.2% 21.6KiB         prek prek::archive::unzip::{{closure}}
 0.1%   0.2% 21.3KiB clap_builder clap_builder::parser::parser::Parser::get_matches_with
 0.1%   0.2% 20.3KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 20.1KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 19.6KiB         prek <prek::languages::ruby::ruby::Ruby as prek::languages::LanguageImpl>::install::{{closure}}
 0.1%   0.2% 19.2KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.9KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.6KiB         ring ring_core_0_17_14__x25519_ge_frombytes_vartime
 0.1%   0.2% 18.2KiB   hyper_util hyper_util::client::legacy::client::Client<C,B>::send_request::{{closure}}
 0.1%   0.2% 18.1KiB    [Unknown] fe_loose_invert
 0.1%   0.2% 17.7KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
36.6%  91.8%  8.2MiB              And 19623 smaller methods. Use -n N to show more.
39.9% 100.0%  8.9MiB              .text section size, the file size is 22.3MiB

Base Branch Results

 File  .text    Size        Crate Name
 0.3%   0.8% 71.9KiB        prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.2%   0.6% 53.3KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 49.4KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 47.0KiB         prek prek::run::{{closure}}
 0.2%   0.5% 42.4KiB         prek prek::cli::run::run::run::{{closure}}
 0.2%   0.4% 35.1KiB         prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.1%   0.3% 31.7KiB        prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.1%   0.3% 29.2KiB  serde_json? <&mut serde_json::de::Deserializer<R> as serde_core::de::Deserializer>::deserialize_struct
 0.1%   0.3% 27.6KiB         prek prek::identify::by_extension::{{closure}}
 0.1%   0.2% 21.5KiB         prek prek::archive::unzip::{{closure}}
 0.1%   0.2% 21.3KiB clap_builder clap_builder::parser::parser::Parser::get_matches_with
 0.1%   0.2% 20.3KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 20.1KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 19.6KiB         prek <prek::languages::ruby::ruby::Ruby as prek::languages::LanguageImpl>::install::{{closure}}
 0.1%   0.2% 19.2KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.9KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
 0.1%   0.2% 18.6KiB         ring ring_core_0_17_14__x25519_ge_frombytes_vartime
 0.1%   0.2% 18.2KiB   hyper_util hyper_util::client::legacy::client::Client<C,B>::send_request::{{closure}}
 0.1%   0.2% 18.1KiB    [Unknown] fe_loose_invert
 0.1%   0.2% 17.7KiB         prek prek::cli::run::filter::collect_files_from_args::{{closure}}
36.6%  91.8%  8.1MiB              And 19605 smaller methods. Use -n N to show more.
39.9% 100.0%  8.9MiB              .text section size, the file size is 22.3MiB

codecov · 2026-01-16T06:01:36Z

Codecov Report

❌ Patch coverage is 97.36842% with 5 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.23%. Comparing base (29464fb) to head (8f4f345).
⚠️ Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
...ates/prek/src/hooks/pre_commit_hooks/check_toml.rs	0.00%	4 Missing ⚠️
crates/prek/src/hooks/builtin_hooks/check_json5.rs	98.70%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1367      +/-   ##
==========================================
+ Coverage   90.04%   90.23%   +0.19%     
==========================================
  Files          80       81       +1     
  Lines       15928    15952      +24     
==========================================
+ Hits        14342    14395      +53     
+ Misses       1586     1557      -29

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Copilot

Pull request overview

This pull request adds support for check-json5 as a builtin hook to validate JSON5 files, addressing issue #823. JSON5 is an extension of JSON that allows comments, unquoted keys, trailing commas, and other features that make configuration files more human-friendly.

Changes:

Added check-json5 builtin hook with full validation support for JSON5 files
Refactored multiple hook implementations to use a new shared run_concurrent_file_checks helper function
Updated documentation to list the new check-json5 hook
Added comprehensive tests for the new hook

Reviewed changes

Copilot reviewed 20 out of 21 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
crates/prek/src/hooks/builtin_hooks/check_json5.rs	New module implementing JSON5 validation logic with unit tests
crates/prek/src/hooks/builtin_hooks/mod.rs	Registered check-json5 hook in the builtin hooks enum and manifest
crates/prek/src/hooks/mod.rs	Added reusable `run_concurrent_file_checks` helper function
crates/prek/tests/builtin_hooks.rs	Added integration test for check-json5 hook
docs/builtin.md	Updated documentation to include check-json5 in supported hooks list
Cargo.toml, crates/prek/Cargo.toml	Added json5 dependency
Cargo.lock	Lock file updates for json5 and ucd-trie dependencies
Multiple hook files	Refactored to use new `run_concurrent_file_checks` helper

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Copilot · 2026-01-16T06:40:11Z

crates/prek/src/hooks/builtin_hooks/check_json5.rs

+        "#};
+        let file_path = create_test_file(&dir, "duplicate.json5", content.as_bytes()).await?;
+        let (code, output) = check_file(dir.path(), &file_path).await?;
+        assert_eq!(code, 0);


The test for duplicate keys expects the check to pass (code 0), but the check-json hook explicitly fails on duplicate keys. This inconsistency may be intentional if JSON5 allows duplicate keys by spec, but it should be documented. Consider adding a comment explaining why duplicate keys are acceptable in JSON5 but not in JSON, or if this is a limitation of the json5 library being used.

@copilot open a new pull request to apply changes based on this feedback

crates/prek/src/hooks/builtin_hooks/check_json5.rs

Copilot · 2026-01-16T06:41:28Z

@j178 I've opened a new pull request, #1368, to work on those changes. Once the pull request is ready, I'll request review from you.

* Initial plan * Add documentation explaining duplicate key behavior in JSON5 Co-authored-by: j178 <[email protected]> --------- Co-authored-by: copilot-swe-agent[bot] <[email protected]> Co-authored-by: j178 <[email protected]>

j178 added 3 commits January 16, 2026 13:25

Add check-json5 as builtin hooks

f60432d

Refactor

65c202e

Add tests

93a4fb1

j178 added the enhancement New feature or request label Jan 16, 2026

j178 changed the title ~~json5~~ Add check-json5 as builtin hooks Jan 16, 2026

j178 marked this pull request as ready for review January 16, 2026 06:28

Tweak

73f68e6

j178 requested a review from Copilot January 16, 2026 06:37

Copilot started reviewing on behalf of j178 January 16, 2026 06:37 View session

Copilot AI reviewed Jan 16, 2026

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Copilot AI mentioned this pull request Jan 16, 2026

Document JSON5 duplicate key behavior in test #1368

Merged

Document JSON5 duplicate key behavior in test (#1368)

8f4f345

* Initial plan * Add documentation explaining duplicate key behavior in JSON5 Co-authored-by: j178 <[email protected]> --------- Co-authored-by: copilot-swe-agent[bot] <[email protected]> Co-authored-by: j178 <[email protected]>

j178 merged commit 352685f into master Jan 16, 2026
17 checks passed

j178 deleted the json5 branch January 16, 2026 06:51

BrewTestBot mentioned this pull request Jan 16, 2026

prek 0.2.29 Homebrew/homebrew-core#263109

Merged

ulgens mentioned this pull request Jan 17, 2026

Be explicit about using builtin hooks ulgens/django-blasphemy#908

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Add check-json5 as builtin hooks#1367

Add check-json5 as builtin hooks#1367
j178 merged 5 commits intomasterfrom
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