f5d0a452ba
The Rust Book recommends that functions that return a `Result` type have a doc comment with an `# Errors` section describing the kind of errors that can be returned (https://doc.rust-lang.org/book/ch14-02-publishing-to-crates-io.html#commonly-used-sections). This change adds a lint to enforce this. The lint is allow by default; it can be enabled with `#![warn(clippy::missing_errors_doc)]`. Closes #4854.