clippy::path_ends_with_ext: Looks for calls to Path::ends_with calls where the argument looks like a file extension. By default, Clippy has a short list of known filenames that start with a dot but aren’t necessarily file extensions (e.g

fn is_markdown(path: &Path) -> bool {
    path.ends_with(".md")
}

fn is_markdown(path: &Path) -> bool {
    path.extension().is_some_and(|ext| ext == "md")
}

#[allow(clippy::path_ends_with_ext)]
fn my_function() { /* ... */ }

[lints.clippy]
path_ends_with_ext = "allow"

cargo clippy -- -A clippy::path-ends-with-ext

Clippy's own documentation

What it does

Looks for calls to Path::ends_with calls where the argument looks like a file extension.

By default, Clippy has a short list of known filenames that start with a dot but aren’t necessarily file extensions (e.g. the .git folder), which are allowed by default. The allowed-dotfiles configuration can be used to allow additional file extensions that Clippy should not lint.

Why is this bad?

This doesn’t actually compare file extensions. Rather, ends_with compares the given argument to the last component of the path and checks if it matches exactly.

Known issues

File extensions are often at most three characters long, so this only lints in those cases in an attempt to avoid false positives. Any extension names longer than that are assumed to likely be real path components and are therefore ignored.

Example

fn is_markdown(path: &Path) -> bool {
    path.ends_with(".md")
}

Use instead:

fn is_markdown(path: &Path) -> bool {
    path.extension().is_some_and(|ext| ext == "md")
}

Configuration

• allowed-dotfiles: Additional dotfiles (files or directories starting with a dot) to allow

  (default: [])

From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.

Related lints

• non_canonical_clone_implnon-canonical implementation of `clone` on a `Copy` type
• non_canonical_partial_ord_implChecks for non-canonical implementations of PartialOrd when Ord is already implemented
• octal_escapesoctal-looking escape in a literal
• permissions_set_readonly_falsecall to `set_readonly` with argument `false`
• pointers_in_nomem_asm_blockpassing pointers to nomem asm block
• possible_missing_elsethis looks like an `else {..}` but the `else` is missing

All 847 Clippy lints · Rust compiler errors · Cargo.toml checker