[cargo-zerocopy] Auto-install targets, more components

[joshlf]

Auto-install any --target arguments. Auto-install all of the following
components: rust-src, rustfmt, clippy, miri (nightly only)

---

• 　  [ci] Re-enable zizmor #3119
• 👉 [cargo-zerocopy] Auto-install targets, more components #3118

Latest Update: v4 — Compare vs v3

📚 Full Patch History

Links show the diff between the row version and the column version.

Version	v3	v2	v1	Base
v4	vs v3	vs v2	vs v1	vs Base
v3		vs v2	vs v1	vs Base
v2			vs v1	vs Base
v1				vs Base

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Branch

git fetch origin refs/heads/Gj5ggnjidkmm6c3foelh4ou7sbi55y4qr && git checkout -b pr-Gj5ggnjidkmm6c3foelh4ou7sbi55y4qr FETCH_HEAD

Checkout

git fetch origin refs/heads/Gj5ggnjidkmm6c3foelh4ou7sbi55y4qr && git checkout FETCH_HEAD

Cherry Pick

git fetch origin refs/heads/Gj5ggnjidkmm6c3foelh4ou7sbi55y4qr && git cherry-pick FETCH_HEAD

Pull

git pull origin refs/heads/Gj5ggnjidkmm6c3foelh4ou7sbi55y4qr

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[gemini-code-assist]

Summary of Changes

Hello, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the cargo-zerocopy utility by automating the setup of required Rust toolchain components and build targets. It introduces a more robust and user-friendly mechanism for ensuring that all necessary dependencies are present, reducing manual intervention and potential setup errors for developers working with different targets or requiring specific tools like clippy or miri.

Highlights

• Automatic Target Installation: The cargo-zerocopy tool now automatically detects and installs any missing Rust targets specified via --target arguments or the CARGO_BUILD_TARGET environment variable, streamlining cross-compilation workflows.
• Enhanced Toolchain Component Installation: The toolchain installation logic has been updated to automatically install essential components: rust-src, rustfmt, clippy, and miri (for nightly toolchains), ensuring a complete development environment.
• Refactored Installation Logic: A new generic ensure_installed_or_exit function was introduced to centralize the logic for checking installation status, prompting the user for confirmation, and executing installations, improving code reusability and maintainability.

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Changelog

• tools/cargo-zerocopy/src/main.rs
  • Imported HashSet, BufRead, and Write for new functionality.
  • Removed the is_toolchain_installed function.
  • Introduced ensure_installed_or_exit to abstract common installation prompting and execution logic.
  • Modified install_toolchain_or_exit to use the new ensure_installed_or_exit function and to install rust-src, rustfmt, clippy, and miri (for nightly) components.
  • Added install_targets_or_exit to automatically detect and install missing Rust targets.
  • Updated delegate_cargo to parse --target arguments and CARGO_BUILD_TARGET environment variable, then call install_targets_or_exit.

Activity

• No human activity has been recorded on this pull request yet.

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[gemini-code-assist]

Code Review

This pull request refactors the toolchain installation logic to be more generic and adds auto-installation for rustup components (rust-src, rustfmt, clippy, miri) and any specified --target arguments. The changes are well-structured, using a new ensure_installed_or_exit helper function to handle the installation prompt and logic. My review focuses on improving robustness by handling potential panics from I/O operations and invalid UTF-8 output from external commands, as well as a minor simplification to remove an unnecessary string allocation.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.87%. Comparing base (4212573) to head (09034d8).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3118   +/-   ##
=======================================
  Coverage   91.87%   91.87%           
=======================================
  Files          20       20           
  Lines        6057     6057           
=======================================
  Hits         5565     5565           
  Misses        492      492           

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