Strange behaviour of a seek_from_start attribute

[anti-social]

Following example looks strange for me:

use deku::{DekuContainerRead, DekuRead, DekuWrite};

#[derive(Debug, DekuRead, DekuWrite, PartialEq)]
#[deku(endian = "big")]
pub struct TestSeek {
    pub a: u8,
    #[deku(seek_from_start = "2")]
    pub b: u8,
    pub c: u8,
}

#[test]
fn test_seek() -> anyhow::Result<()> {
    let data: &[u8] = &[0, 1, 2, 3];
    let test = TestSeek::from_bytes((data, 0))?;
    println!("> {test:?}");
    Ok(())
}

It produces following output:

> (([3], 0), TestSeek { a: 0, b: 2, c: 3 })

As you can see not all bytes are consumed. Is it expected behavior or a bug?

[sharksforarms]

~Hm, that does look odd. I would have expected maybe see'ing a rest of [1], not [3], ~ wdyt @wcampbell0x2a ?

edit: what's happening here is we're reading 3 bytes, so the current read 'position' is:

[0, 1, 2, 3]
        ^

agreed that it looks confusing however. We should probably track the position in a better way to take seeks into account?

[wcampbell0x2a]

I don't have time to fully test this or think about it, but this could be a possible solution #526