[derive] Refactor into more modules

[joshlf]

• Move most top-level derive code into modules under a new top-level
  derive module
• Move some utilities into util
• Leave the root module to primarily perform routing and scaffolding

---

• 👉 [derive] Refactor into more modules #2901

Latest Update: v7 — Compare vs v6

📚 Full Patch History

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

Version	v6	v5	v4	v3	v2	v1	Base
v7	vs v6	vs v5	vs v4	vs v3	vs v2	vs v1	vs Base
v6		vs v5	vs v4	vs v3	vs v2	vs v1	vs Base
v5			vs v4	vs v3	vs v2	vs v1	vs 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

[gemini-code-assist]

Summary of Changes

Hello @joshlf, 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 undertakes a substantial internal refactoring of the zerocopy-derive crate. The primary goal is to improve the codebase's modularity and maintainability by organizing derive macro implementations into a more structured hierarchy. This change centralizes shared utilities and simplifies the main entry point, making the project easier to navigate and extend in the future.

Highlights

• Module Restructuring: The zerocopy-derive crate has been significantly refactored, moving most top-level derive code into a new derive module with dedicated sub-modules for each trait implementation.
• Utility Consolidation: Common utility functions, enums, and helper structs (like PaddingCheck, Trait, and ImplBlockBuilder) have been moved and consolidated into src/util.rs for better organization.
• Centralized Routing: The main lib.rs file now primarily handles routing and scaffolding for the derive macros, delegating the core logic to the newly created derive sub-modules.
• Renamed File: The src/enum.rs file has been renamed to src/derive/try_from_bytes.rs, reflecting its new focus and location within the refactored structure.

🧠 New Feature in Public Preview: You can now enable Memory to help Gemini Code Assist learn from your team's feedback. This makes future code reviews more consistent and personalized to your project's style. Click here to enable Memory in your admin console.

Using Gemini Code Assist

The full guide for Gemini Code Assist can be found on our documentation page, here are some quick tips.

Invoking Gemini

You can request assistance from Gemini at any point by creating a comment using either /gemini <command> or @gemini-code-assist <command>. Below is a summary of the supported commands on the current page.

Feature	Command	Description
Code Review	/gemini review	Performs a code review for the current pull request in its current state.
Pull Request Summary	/gemini summary	Provides a summary of the current pull request in its current state.
Comment	@gemini-code-assist	Responds in comments when explicitly tagged, both in pull request comments and review comments.
Help	/gemini help	Displays a list of available commands.

Customization

To customize Gemini Code Assist for GitHub experience, repository maintainers can create a configuration file and/or provide a custom code review style guide (such as PEP-8 for Python) by creating and adding files to a .gemini/ folder in the base of the repository. Detailed instructions can be found here.

Limitations & Feedback

Gemini Code Assist may make mistakes. Please leave feedback on any instances where its feedback is incorrect or counter productive. You can react with 👍 and 👎 on @gemini-code-assist comments. If you're interested in giving your feedback about your experience with Gemini Code Assist for Github and other Google products, sign up here.

You can also get AI-powered code generation, chat, as well as code reviews directly in the IDE at no cost with the Gemini Code Assist IDE Extension.

Footnotes

1. Review the Privacy Notices, Generative AI Prohibited Use Policy, Terms of Service, and learn how to configure Gemini Code Assist in GitHub here. Gemini can make mistakes, so double check it and use code with caution. ↩

[gemini-code-assist]

Code Review

This pull request is a work-in-progress that refactors the zerocopy-derive crate by moving derive logic into a new derive module. This is a great step towards better organization and maintainability. The code has been moved logically into different files under the new module. My main feedback is to improve the naming consistency of the newly created derive functions for better long-term maintenance.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.90%. Comparing base (1a44860) to head (9363bd4).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2901   +/-   ##
=======================================
  Coverage   91.90%   91.90%           
=======================================
  Files          20       20           
  Lines        5877     5877           
=======================================
  Hits         5401     5401           
  Misses        476      476           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[joshlf]

/gemini review

[gemini-code-assist]

Code Review

This pull request is a large but well-executed refactoring of the zerocopy-derive crate. It moves derive logic from lib.rs into a new derive module with a clearer structure, which significantly improves code organization and maintainability. The logic appears to be preserved correctly throughout the move. I've found one issue in the test setup where function paths were not fully updated to reflect the new structure, which will cause test compilation to fail. Overall, this is a great improvement to the codebase.