packbits 0.1.1

Tiny, zero-boilerplate bit packing for your own structs: convert to/from fixed-size byte arrays and integer containers with one attribute.
Documentation 
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#![allow(dead_code)]

use packbits as _;

#[packbits::pack(u8)]
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
struct Flags {
  // Test inferred width for bool
  a: bool,
  #[bits(3)]
  b: u8,
  #[bits(4)]
  c: u8,
}

#[test]
fn roundtrip_flags_from_u8_and_back() {
  // For all possible u8 values, ensure roundtrip via From/Into exists
  for v in 0u16..=255 {
    let v8 = v as u8;
    let f: Flags = v8.into();
    let back: u8 = f.into();
    assert_eq!(back, v8);
  }
}

#[packbits::pack]
#[derive(Clone, Copy, Debug, PartialEq, Eq)]
struct DefaultBytesOne {
  #[bits(3)]
  lo: u8,
  #[bits(5)]
  hi: u8,
}

#[test]
fn default_bytes_is_one() {
  // No bytes specified → defaults to 1
  for lo in 0u8..=7 {
    for hi in 0u8..=31 {
      let s = DefaultBytesOne { lo, hi };
      let b: u8 = s.into();
      let s2: DefaultBytesOne = b.into();
      assert_eq!(s2, DefaultBytesOne { lo, hi });
    }
  }
}