libpso/src/util.rs

pub fn array_to_utf8<const X: usize>(array: [u8; X]) -> Result<String, std::string::FromUtf8Error> {
    String::from_utf8(array.to_vec())
        .map(|mut s| {
            if let Some(index) = s.find("\u{0}") {
                s.truncate(index);
            }
            s
        })
}

pub fn array_to_utf16(array: &[u8]) -> String {
    unsafe {
        let (_, data, _) = array.align_to();
        String::from_utf16_lossy(&data).trim_matches(char::from(0)).into()
    }
}


// TODO: const fn version of this! (helpful with tests)
#[macro_export]
macro_rules! utf8_to_array {
    ($s: expr, $size: expr) => {
        {
            let mut array = [0u8; $size];
            let bytes = $s.as_bytes();
            array[..bytes.len()].clone_from_slice(&bytes);
            array
        }
    }
}

#[macro_export]
macro_rules! utf8_to_utf16_array {
    ($s: expr, $size: expr) => {
        {
            let mut array = [0u16; $size];
            //let bytes = $s.as_bytes();
            let bytes = $s.encode_utf16().collect::<Vec<_>>();
            array[..bytes.len()].clone_from_slice(&bytes);
            array
        }
    }
}

pub fn vec_to_array<T: Default + Copy, const N: usize>(vec: Vec<T>) -> [T; N] {
    let mut result: [T; N] = [T::default(); N];
    for (i, v) in vec.into_iter().enumerate() {
        result[i] = v
    }
    result
}

#[cfg(test)]
mod test {
    #[test]
    fn test_utf8_to_array() {
        let s = "asdf".to_owned();
        let a = utf8_to_array!(s, 8);

        let mut e = [0u8; 8];
        e[..4].clone_from_slice(b"asdf");
        assert!(a == e);
    }

    #[test]
    fn utf8_to_utf16_array() {
        let utf16 = utf8_to_utf16_array!("asdf", 16);
        assert!(utf16 == [97, 115, 100, 102, 0,0,0,0,0,0,0,0,0,0,0,0])
    }

    #[test]
    fn utf8_to_utf16_array_unicode() {
        let utf16 = utf8_to_utf16_array!("あいうえお", 16);
        assert!(utf16 == [0x3042 , 0x3044, 0x3046, 0x3048, 0x304A, 0,0,0,0,0,0,0,0,0,0,0])
    }
}