Refactor Rust toolchain management

[j178]

Finish some TODOs after #989

• Reuse system installed rustup
• Reuse installed rustup across hooks
• Reuse installed Rust toolchains across hooks

[codecov]

Codecov Report

❌ Patch coverage is 84.63542% with 59 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.62%. Comparing base (db20094) to head (e950caf).

Files with missing lines	Patch %	Lines
src/languages/rust/version.rs	74.48%	25 Missing ⚠️
src/languages/rust/rustup.rs	88.94%	21 Missing ⚠️
src/languages/rust/installer.rs	85.93%	9 Missing ⚠️
src/languages/rust/rust.rs	86.20%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1198      +/-   ##
==========================================
+ Coverage   89.58%   89.62%   +0.04%     
==========================================
  Files          78       79       +1     
  Lines       14823    14933     +110     
==========================================
+ Hits        13279    13384     +105     
- Misses       1544     1549       +5     

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[github-actions]

📦 Cargo Bloat Comparison

Binary size change: +0.00% (16.7 MiB → 16.7 MiB)

Expand for cargo-bloat output

Head Branch Results

 File  .text     Size          Crate Name
 0.6%   1.3% 104.8KiB          prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.6%   1.2%  98.5KiB           prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.3%   0.7%  54.6KiB           prek prek::archive::unpack::{{closure}}
 0.3%   0.7%  53.0KiB             h2 h2::proto::connection::Connection<T,P,B>::poll
 0.2%   0.5%  40.0KiB           prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.2%   0.5%  39.1KiB          prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.2%   0.5%  38.3KiB           prek prek::run::{{closure}}
 0.2%   0.5%  37.3KiB regex_automata regex_automata::meta::strategy::new
 0.2%   0.4%  35.2KiB           prek prek::workspace::Workspace::discover
 0.2%   0.4%  31.4KiB           std? <core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize
 0.2%   0.4%  30.8KiB           prek <prek::languages::rust::rust::Rust as prek::languages::LanguageImpl>::install::{{closure}}
 0.2%   0.4%  30.4KiB           prek prek::cli::run::run::run::{{closure}}
 0.2%   0.4%  30.3KiB           prek prek::languages::rust::installer::RustInstaller::install::{{closure}}
 0.2%   0.4%  28.8KiB           prek prek::languages::node::installer::NodeInstaller::install::{{closure}}
 0.2%   0.4%  28.1KiB             h2 h2::proto::connection::DynConnection<B>::recv_frame
 0.2%   0.3%  27.6KiB           prek prek::identify::by_extension::{{closure}}
 0.1%   0.3%  25.1KiB           prek prek::main
 0.1%   0.3%  24.4KiB     hyper_util hyper_util::client::legacy::client::Client<C,B>::send_request::{{closure}}
 0.1%   0.3%  24.4KiB           std? <core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize
 0.1%   0.3%  24.3KiB     hyper_util hyper_util::client::legacy::client::Client<C,B>::connect_to::{{closure}}::{{closure}}::{{closure}}
41.1%  88.8%   6.9MiB                And 10667 smaller methods. Use -n N to show more.
46.3% 100.0%   7.7MiB                .text section size, the file size is 16.7MiB

Base Branch Results

 File  .text     Size          Crate Name
 0.6%   1.3% 104.8KiB          prek? <prek::cli::Command as clap_builder::derive::Subcommand>::augment_subcommands
 0.6%   1.3% 100.4KiB           prek prek::languages::<impl prek::config::Language>::run::{{closure}}::{{closure}}
 0.3%   0.7%  54.6KiB           prek prek::archive::unpack::{{closure}}
 0.3%   0.7%  53.0KiB             h2 h2::proto::connection::Connection<T,P,B>::poll
 0.2%   0.5%  40.0KiB           prek prek::languages::<impl prek::config::Language>::install::{{closure}}
 0.2%   0.5%  39.1KiB          prek? <prek::cli::RunArgs as clap_builder::derive::Args>::augment_args
 0.2%   0.5%  38.3KiB           prek prek::run::{{closure}}
 0.2%   0.5%  37.3KiB regex_automata regex_automata::meta::strategy::new
 0.2%   0.4%  35.2KiB           prek prek::workspace::Workspace::discover
 0.2%   0.4%  31.4KiB           std? <core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize
 0.2%   0.4%  30.4KiB           prek prek::cli::run::run::run::{{closure}}
 0.2%   0.4%  28.8KiB           prek prek::languages::node::installer::NodeInstaller::install::{{closure}}
 0.2%   0.4%  28.1KiB             h2 h2::proto::connection::DynConnection<B>::recv_frame
 0.2%   0.3%  27.6KiB           prek prek::identify::by_extension::{{closure}}
 0.1%   0.3%  25.1KiB           prek prek::main
 0.1%   0.3%  24.4KiB     hyper_util hyper_util::client::legacy::client::Client<C,B>::send_request::{{closure}}
 0.1%   0.3%  24.4KiB           std? <core::marker::PhantomData<T> as serde_core::de::DeserializeSeed>::deserialize
 0.1%   0.3%  24.3KiB     hyper_util hyper_util::client::legacy::client::Client<C,B>::connect_to::{{closure}}::{{closure}}::{{closure}}
 0.1%   0.3%  24.2KiB           prek prek::hook::HookBuilder::build::{{closure}}
 0.1%   0.3%  23.9KiB          hyper hyper::proto::h1::dispatch::Dispatcher<D,Bs,I,T>::poll_loop
41.2%  88.9%   6.9MiB                And 10629 smaller methods. Use -n N to show more.
46.3% 100.0%   7.7MiB                .text section size, the file size is 16.7MiB

[Copilot]

Pull request overview

This PR refactors Rust toolchain management to use rustup more efficiently and reuse installations across hooks, as indicated by the completion of TODOs from issue #989.

Key Changes:

• Migrated from standalone Rust installation to unified rustup-based management
• Introduced reuse of system-installed rustup and installed toolchains across hooks
• Renamed storage buckets: ToolBucket::Rust → ToolBucket::Rustup and CacheBucket::Rust → CacheBucket::Cargo

Reviewed changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/languages/rust/rustup.rs	New module implementing rustup installation and toolchain management with system detection
src/languages/rust/version.rs	Enhanced Rust version representation with channel support (stable/beta/nightly) and toolchain name generation
src/languages/rust/installer.rs	Refactored to use Rustup abstraction instead of direct rustup commands, simplified toolchain discovery
src/languages/rust/rust.rs	Updated to use shared cargo_home cache and new rustup-based installer
src/languages/rust/mod.rs	Added rustup module export
src/store.rs	Renamed buckets: Rust → Rustup for tools, Rust → Cargo for cache
tests/languages/rust.rs	Updated test paths to reflect new tools/rustup/toolchains structure, added rustup installer test
tests/run.rs	Removed redundant system-rust test (coverage exists in tests/languages/rust.rs)
crates/prek-consts/src/env_vars.rs	Renamed constant from PREK_INTERNAL__RUST_BINARY_NAME to PREK_INTERNAL__RUSTUP_BINARY_NAME
docs/todo.md	Moved Rust from "WIP" to "Supported" status
src/languages/golang/golang.rs	Minor import cleanup (using ToolBucket directly instead of fully qualified path)

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[j178]

Hey @lmmx, would you be interested in taking a look at this?