Commit 985f1f09 authored by Milan Landaverde's avatar Milan Landaverde Committed by Miguel Ojeda
Browse files

rust: str: add `CStr` unit tests 



Add unit tests for `CStr::from_bytes_with_nul()` and
`CStr::from_bytes_with_nul_unchecked()`.

These serve as an example of the first unit tests for Rust code
(i.e. different from documentation tests).

Signed-off-by: default avatarMilan Landaverde <milan@mdaverde.com>
[Reworded, adapted for upstream and applied latest changes]
Signed-off-by: default avatarMiguel Ojeda <ojeda@kernel.org>
parent c07e67bd

rust/kernel/str.rs

+29 −0
Original line number Diff line number Diff line
@@ -321,6 +321,35 @@ fn index(&self, index: Idx) -> &Self::Output { 
    }

}



#[cfg(test)]

mod tests {

    use super::*;



    #[test]

    fn test_cstr_to_str() {

        let good_bytes = b"\xf0\x9f\xa6\x80\0";

        let checked_cstr = CStr::from_bytes_with_nul(good_bytes).unwrap();

        let checked_str = checked_cstr.to_str().unwrap();

        assert_eq!(checked_str, "🦀");

    }



    #[test]

    #[should_panic]

    fn test_cstr_to_str_panic() {

        let bad_bytes = b"\xc3\x28\0";

        let checked_cstr = CStr::from_bytes_with_nul(bad_bytes).unwrap();

        checked_cstr.to_str().unwrap();

    }



    #[test]

    fn test_cstr_as_str_unchecked() {

        let good_bytes = b"\xf0\x9f\x90\xA7\0";

        let checked_cstr = CStr::from_bytes_with_nul(good_bytes).unwrap();

        let unchecked_str = unsafe { checked_cstr.as_str_unchecked() };

        assert_eq!(unchecked_str, "🐧");

    }

}



/// Allows formatting of [`fmt::Arguments`] into a raw buffer.

///

/// It does not fail if callers write past the end of the buffer so that they can calculate the