draco-oxide 0.1.0-alpha.5

draco-oxide is a rust rewrite of Google's draco mesh compression library.
Documentation 
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use crate::{
    core::bit_coder::ReaderErr,
    prelude::{ByteReader, ByteWriter},
};

#[allow(unused)]
pub(crate) fn leb128_read<W>(reader: &mut W) -> Result<u64, ReaderErr>
where
    W: ByteReader,
{
    let mut result: u64 = 0;
    let mut shift = 0;
    loop {
        let byte = reader.read_u8()?;
        result |= ((byte & 0x7F) as u64) << shift;
        if byte & 0x80 == 0 {
            break;
        }
        shift += 7;
    }
    Ok(result)
}

pub(crate) fn leb128_write<W>(mut value: u64, writer: &mut W)
where
    W: ByteWriter,
{
    loop {
        let byte = (value & 0x7F) as u8;
        value >>= 7;
        if value == 0 {
            writer.write_u8(byte);
            break;
        } else {
            writer.write_u8(byte | 0x80);
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn manual_test_leb128_write_read() {
        let mut buffer = Vec::new();
        leb128_write(300, &mut buffer);
        assert_eq!(buffer, vec![172, 2]);

        let mut reader = buffer.into_iter();
        let value = leb128_read(&mut reader).unwrap();
        assert_eq!(value, 300);
    }

    #[test]
    fn more_tests_leb128() {
        let testdata = vec![0, 1, 127, 128, 255, 256, 1234567890, 0xFFFFFFFFFFFFFFFF];
        let mut buffer = Vec::new();
        for &value in &testdata {
            leb128_write(value, &mut buffer);
        }
        let mut reader = buffer.into_iter();
        for &expected in &testdata {
            let value = leb128_read(&mut reader).unwrap();
            assert_eq!(value, expected);
        }
        assert!(
            reader.next().is_none(),
            "Reader should be empty after reading all values"
        );
    }
}