cartouche 0.2.0

Encoding and decoding for HDMI InfoFrames.
Documentation 
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use super::*;

#[test]
fn checksum_makes_total_zero() {
    let header_and_payload = [
        0x82, 0x02, 0x0D, // header bytes (type, version, length)
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // payload
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, //
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, //
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    ];
    let checksum = compute_checksum(&header_and_payload);
    let sum: u8 = header_and_payload
        .iter()
        .fold(0u8, |acc, &b| acc.wrapping_add(b))
        .wrapping_add(checksum);
    assert_eq!(sum, 0x00);
}

#[test]
fn all_zeros_gives_zero_checksum() {
    assert_eq!(compute_checksum(&[0u8; 30]), 0x00);
}

#[test]
fn known_value() {
    // sum of [0x82, 0x02, 0x0D, rest zeros] = 0x82 + 0x02 + 0x0D = 0x91
    // checksum = 256 - 0x91 = 0x6F
    let mut bytes = [0u8; 30];
    bytes[0] = 0x82;
    bytes[1] = 0x02;
    bytes[2] = 0x0D;
    assert_eq!(compute_checksum(&bytes), 0x6F);
}