review-and-fix
Deep analysis and iterative fixing of a Rust source file. Finds logic errors, lock/concurrency issues, and simplification opportunities, then fixes them one by one until the file is clean.
Install
mkdir -p .claude/skills/review-and-fix && curl -L -o skill.zip "https://agentskills.codes/api/skills/download/16696" && unzip -o skill.zip -d .claude/skills/review-and-fix && rm skill.zipInstalls to .claude/skills/review-and-fix
Activation
This is the description your AI agent reads to decide when to run this skill — the better it matches your request, the more reliably it fires.
Deep analysis and iterative fixing of a Rust source file. Finds logic errors, lock/concurrency issues, and simplification opportunities, then fixes them one by one until the file is clean.About this skill
review-and-fix
Deep-analyze the specified file, find logic errors, memory/lock issues, and simplification opportunities, and fix them iteratively until no problems remain.
Usage
/review-and-fix <file_path>
Examples
/review-and-fix src/mqtt-broker/src/subscribe/buckets.rs
/review-and-fix src/mqtt-broker/src/subscribe/directly_push.rs
Execution Flow
Each round follows this sequence until nothing left to fix:
1. Read
Fully read the target file. Read related files as needed (callers, struct definitions it depends on) to understand context.
2. Analyze
Check in priority order:
Logic Errors (must fix)
- Asymmetric data structure operations:
addwrites N indexes,removeonly cleans N-1 - offset/commit semantics: committing after push failure causes message loss
- Key collisions: separator choice produces identical keys for different inputs
Concurrency/Lock Issues (must fix)
- DashMap
entry(),get(),get_mut()returnRef/RefMutthat hold shard locks — not released during.await RwLockread lock held during.awaitblocks write lock- Fix:
.clone()the data to drop the guard before awaiting; or storeArc<T>
Simplification (apply judiciously)
- Repeated
get_mut+else { insert }→entry().or_default() - Redundant
else { return x }→ remove the else - Two-step
let x = ...; let x = match x { Some(v) => v, None => return }→let Some(x) = ... else { return } - Nested
if !condition { ... }→if condition { continue } - Duplicate import lines → merge
- Temporary flag variables (
let mut failed = false; ... if !failed { commit() }) → early return
Comments (keep lean)
- Remove redundant or obvious comments; the code should speak for itself
- Keep only comments that explain a non-obvious why (an invariant, a subtle ordering, a footgun)
- Do not over-comment — fewer, higher-signal comments beat many noisy ones
Test Cases (deep review, then trim — do not just add)
- Deep-review every existing test before adding anything: does it assert a real behavior, or just re-exercise the happy path another test already covers? Does the assertion actually fail if the logic under test is broken (mutate the code mentally and check)?
- Default action is consolidation, not addition: merge near-duplicate tests into one parametrized/table-driven case, delete tests that assert trivial defaults or that duplicate coverage another test already provides
- Only add a new test when a real gap exists: a pure decision function or bug-prone branch with zero coverage. One targeted case per gap — do not pad with variations that don't exercise a new path
- Prefer testing the pure/extractable logic directly over standing up heavy mocks for orchestration glue; if a path can only be tested by mocking a large dependency, that's usually a sign to extract the pure logic rather than write the mock
- Keep the total test count as small as possible while still covering every distinct branch/outcome once — "few, focused, high-signal" beats "thorough-looking"
Naming (align names with behavior)
- Function names: does the name describe what the function actually does? Rename misleading or vague names (e.g. a
get_*that mutates, a*_switchthat only computes) - File / module names: does the file name match its content and responsibility? Flag/rename when it has drifted
- When renaming, update every reference (callers, imports,
moddeclarations) and re-runcargo check. Be conservative with widely-used public names — only rename when the current name is genuinely misleading, not for taste
What NOT to do
- Do not refactor correct code just to be "more Rusty"
- Do not introduce new abstractions or traits
- Do not change public API signatures (unless there is a bug, or a name is genuinely misleading — then rename and update all call sites)
- Do not add unnecessary comments
3. Fix
- Only fix issues you are certain about — do not guess
- After each fix, run
cargo check -p <crate>to verify compilation - For core logic changes, run the relevant unit tests
4. Loop
After each round of fixes, re-analyze the file to confirm nothing was missed. Stop only when you can clearly state: "no logic errors, no lock issues, no worthwhile simplification remaining, names match behavior, test coverage adequate and focused, comments lean."
Output Format
- Start each round by stating what problems were found
- After fixing, explain what changed and why
- On the final round, explicitly state "no issues, stopping"
- Do not output meaningless progress descriptions