Macros Code Review

Review Workflow

1. Check Cargo.toml -- Note Rust edition (2024 reserves gen keyword, affecting macro output), proc-macro crate dependencies (syn, quote, proc-macro2), and feature flags (e.g., syn with minimal features)
2. Check macro type -- Determine if reviewing declarative (macro_rules!), function-like proc macro, attribute macro, or derive macro
3. Check if a macro is needed -- If the transformation is type-based, generics are better. Macros are for structural/repetitive code generation that generics cannot express
4. Scan macro definitions -- Read full macro bodies including all match arms, not just the invocation site
5. Check each category -- Work through the checklist below, loading references as needed
6. Gates -- Complete Gates below before reporting; do not substitute informal “I verified.”

Gates (before reporting findings)

Complete in order. Do not emit findings until Gate 4 passes for each issue.

Gate 1 — Crate context (on disk)
PASS when: You opened the reviewed crate’s Cargo.toml (workspace member path if applicable) and recorded Rust edition, whether the crate is proc-macro = true, and relevant proc-macro dependencies or syn / quote feature flags.
Blocks rationalization: Edition 2024 findings (gen, unsafe extern, generated unsafe bodies) and syn “full” vs minimal flags require this — do not flag edition-specific macro output without matching edition from the file.