What it does

Suggest instances where .chars().enumerate() should be replaced with .char_indices() instead for str slices when the index returned by .enumerate() is used in subsequent string slice operations like s[i..] or s.split_at(i).

Here is a real world example of this kind of issue: RustPython/RustPython#4444, failure to correctly handle multi-byte character when doing string slice operations leads to panic at runtime.

Lint Name

No response

Category

correctness

Advantage

• Correctly handle multi-byte character in string slice operations

Drawbacks

No response

Example

let s = "{a:%ЫйЯЧ}";
for (i, c) in s.chars().enumerate() {
    let (_left, _right) = s.split_at(i);
}

Playground