byte-mutator 0.1.2

Library to define staged mutations for a series of bytes
Documentation 
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//! Performs a walking bit flip of `width` bits. A width of 1 will flip a single bit.

#[derive(Debug, Copy, Clone)]
pub struct BitFlipper {}

impl BitFlipper {
    pub fn mutate(bytes: &mut [u8], i: usize, _width: u8) {
        let i = i % (bytes.len() * 8);
        let byte = i / 8;
        let bit = i % 8;
        let v: u8 = bytes[byte] ^ 1 << bit as u8;

        // todo: Implement width
        bytes[byte] = v;
    }
}

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

    #[test]
    fn flip_bit() {
        let mut buffer = UndoBuffer::new(b"foo");

        // first bit should flip resulting in 'goo'
        // 0b1100110 -> 0b1100111, 103 -> 102, f -> g
        BitFlipper::mutate(buffer.get_mut(), 0, 1);
        assert_eq!(buffer.read(), b"goo");
    }
}