dtolnay

Rust coding style rules inspired by David Tolnay, author of serde, syn, anyhow, thiserror, proc-macro2, and many other foundational Rust crates.

These rules enforce the precise, minimal, type-driven style that dtolnay is known for. They run as edit-time validators, checking every code change in real time.

Rules

Rule	What it enforces
parse-dont-validate	Use parsing and type conversions instead of runtime validation checks
meaningful-error-messages	Error types and messages must help the user fix the problem
no-stringly-typed	Use enums and newtypes instead of raw strings for domain concepts
exhaustive-matching	Match arms must be exhaustive; no wildcard catch-alls hiding bugs
precise-imports	Import specific items, not glob imports
no-unnecessary-allocation	Don't allocate when a borrow or slice will do
derive-order	Derive attributes must follow a canonical order
api-surface-minimality	Public API should expose the minimum necessary surface
lifetime-elision	Don't write lifetime annotations that the compiler can infer
no-type-complexity	Flatten deeply nested generic types into named type aliases
testing-as-documentation	Tests are the spec: named behaviors, one assert per test, trybuild for compile errors
formatting-discipline	Run cargo fmt, then check import grouping, comment style, and what rustfmt misses
test-coverage-intent	Every public fn and every error path must have a test that exercises it
test-isolation-state	Tests touching files, env vars, or any stored state must be fully isolated

Installation

avp install dtolnay