== Why is this an issue? Using `Stdin::read_line` without trimming the newline character can cause runtime issues, especially when parsing the input into another type (e.g., `i32`). The operation will fail if the string contains a trailing newline character, making the code unreliable. === Code examples ==== Noncompliant code example [source,rust,diff-id=1,diff-type=noncompliant] ---- let mut input = String::new(); std::io::stdin().read_line(&mut input).expect("Failed to read a line"); let num: i32 = input.parse().expect("Not a number!"); // Noncompliant: The input string may contain a newline character. ---- ==== Compliant solution [source,rust,diff-id=1,diff-type=compliant] ---- let mut input = String::new(); std::io::stdin().read_line(&mut input).expect("Failed to read a line"); let num: i32 = input.trim_end().parse().expect("Not a number!"); // Compliant: Trims the trailing newline character. ---- == Resources === Documentation * Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#read_line_without_trim