Add language: bun support

[shaanmajid]

Adds language: bun support for running hooks with the Bun JavaScript runtime.

Mirrors the Node.js implementation:

• Downloads from GitHub releases (oven-sh/bun)
• Supports version constraints: bun@1.x, >=1.0, <2.0, paths
• Isolated environments with BUN_INSTALL redirection
• bun install -g for additional dependencies

Ref #619 (keeping issue open since this PR doesn't implement deno support)

[codecov]

Codecov Report

❌ Patch coverage is 92.94404% with 29 lines in your changes missing coverage. Please review.
✅ Project coverage is 90.21%. Comparing base (f1b110c) to head (ec9c1e6).
⚠️ Report is 11 commits behind head on v03.

Files with missing lines	Patch %	Lines
crates/prek/src/languages/bun/installer.rs	90.16%	18 Missing ⚠️
crates/prek/src/languages/bun/bun.rs	95.19%	5 Missing ⚠️
crates/prek/src/languages/bun/version.rs	95.68%	5 Missing ⚠️
crates/prek/src/languages/version.rs	66.66%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              v03    #1411      +/-   ##
==========================================
- Coverage   90.66%   90.21%   -0.46%     
==========================================
  Files          82       86       +4     
  Lines       16698    17808    +1110     
==========================================
+ Hits        15140    16066     +926     
- Misses       1558     1742     +184     

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[github-actions]

📦 Cargo Bloat Comparison

Binary size change: +0.44% (22.6 MiB → 22.7 MiB)

Expand for cargo-bloat output

Head Branch Results

 File  .text    Size        Crate Name
 0.3%   0.8% 77.4KiB        prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.2%   0.6% 58.0KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.6% 53.0KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 46.3KiB         prek prek::run::{{closure}}
 0.2%   0.5% 43.6KiB         prek prek::cli::run::run::run::{{closure}}
 0.2%   0.5% 42.7KiB         prek prek::identify::by_extension::{{closure}}
 0.2%   0.4% 36.5KiB         prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.1%   0.3% 31.8KiB        prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.1%   0.3% 30.0KiB  serde_json? <&mut serde_json::de::Deserializer<R> as serde_core::de::Deserializer>::deserialize_struct
 0.1%   0.2% 22.3KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 22.0KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{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% 20.5KiB        prek? <prek::cli::Cli as clap_builder::derive::FromArgMatches>::from_arg_matches_mut
 0.1%   0.2% 19.7KiB         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
36.9%  91.6%  8.4MiB              And 20026 smaller methods. Use -n N to show more.
40.3% 100.0%  9.2MiB              .text section size, the file size is 22.7MiB

Base Branch Results

 File  .text    Size        Crate Name
 0.3%   0.8% 74.9KiB        prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.2%   0.6% 53.8KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 49.8KiB         prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.2%   0.5% 46.3KiB         prek prek::run::{{closure}}
 0.2%   0.5% 43.6KiB         prek prek::cli::run::run::run::{{closure}}
 0.2%   0.5% 42.7KiB         prek prek::identify::by_extension::{{closure}}
 0.2%   0.4% 35.1KiB         prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.1%   0.3% 31.8KiB        prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.1%   0.3% 30.0KiB  serde_json? <&mut serde_json::de::Deserializer<R> as serde_core::de::Deserializer>::deserialize_struct
 0.1%   0.2% 22.2KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{closure}}
 0.1%   0.2% 22.0KiB         prek prek::hooks::meta_hooks::MetaHooks::run::{{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% 19.6KiB         prek <prek::languages::ruby::ruby::Ruby as prek::languages::LanguageImpl>::install::{{closure}}
 0.1%   0.2% 19.3KiB         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::languages::python::uv::InstallSource::install::{{closure}}
36.8%  91.7%  8.3MiB              And 19982 smaller methods. Use -n N to show more.
40.2% 100.0%  9.1MiB              .text section size, the file size is 22.6MiB

[j178]

This looks really good. I went through all the code in one go without any confusion! I’ll take a closer look tomorrow, thank you!

[j178]

I might want to pull the GitHub token from the GH_TOKEN or GITHUB_TOKEN env vars (and document it in configuration.md) so we can avoid hitting the API rate limit.

[shaanmajid]

Now respects GITHUB_TOKEN (automatically set in GitHub actions) for authentication if set.

I did not yet implement support for GH_TOKEN, which is set by the GitHub CLI:

1. The prek CLI looks like it only uses GITHUB_TOKEN so far
2. This codepath should not run so frequently in real-world use to trigger the rate limit; this is primarily a CI concern

Happy to change if you feel otherwise :)

[j178]

For someone like me living in a country with heavy internet censorship, I have to use a proxy to access GitHub. That means I’m sharing the same busy IP with tons of other people, so hitting the GitHub API rate limit is basically an everyday thing :(

[shaanmajid]

That's a great point -- and sorry for the situation :(

To be clear though, I did add support for GITHUB_TOKEN in f05643f. I'm not sure if I see how supporting GH_TOKEN as well may be different than just supporting GITHUB_TOKEN. Since this isn't being called by the gh CLI in anyway, the user still needs to manually set the environment variable (in e.g. ~/.zshrc). Am I missing something?

Happy again to add GH_TOKEN support as well if you'd prefer it; just want to make sure I fully understand the impact of supporting it.

[j178]

Thanks!