Display bandwidth in different unit families

[cyqsimon]

• Added option -u, --unit-family

  -u, --unit-family <UNIT_FAMILY>
          Choose a specific family of units

          [default: bin-bytes]

          Possible values:
          - bin-bytes: bytes, in powers of 2^10
          - bin-bits:  bits, in powers of 2^10
          - si-bytes:  bytes, in powers of 10^3
          - si-bits:   bits, in powers of 10^3

• Supported families are {binary,SI}-{bytes,bits}

Closes #145; closes #213.

Checklist

• implementation
• tests (do we really need them?)

[sigmaSd]

Ok I tried to add some tests via a pr to your branch but I failed miserably , can you add this please, also I have some couple remarks there as well

mod tests {
    use crate::display::BandwidthUnitFamily;

    #[test]
    fn unit_test() {
        // size < 1024 are not calculated correctly
        {
            let size = 1024.;
            assert_eq!(
                BandwidthUnitFamily::BinBytes.get_unit_for(size),
                (1024., "KiB")
            );
            assert_eq!(
                BandwidthUnitFamily::BinBits.get_unit_for(size),
                (128., "Kib")
            );
            // the next 2 `k` are lowercase
            // should  they be uppercase ?
            // they are uppercase on the next units (M G T)
            assert_eq!(
                BandwidthUnitFamily::SiBytes.get_unit_for(size),
                (1000., "kB")
            );
            assert_eq!(BandwidthUnitFamily::SiBits.get_unit_for(size), (125., "kb"));
        }
        {
            let size = 1024. * 1024.;
            assert_eq!(
                BandwidthUnitFamily::BinBytes.get_unit_for(size),
                (1048576.0, "MiB")
            );
            assert_eq!(
                BandwidthUnitFamily::BinBits.get_unit_for(size),
                (131072.0, "Mib")
            );
            assert_eq!(
                BandwidthUnitFamily::SiBytes.get_unit_for(size),
                (1000000.0, "MB")
            );
            assert_eq!(
                BandwidthUnitFamily::SiBits.get_unit_for(size),
                (125000.0, "Mb")
            );
        }
        {
            let size = 1024. * 1024. * 1024.;
            assert_eq!(
                BandwidthUnitFamily::BinBytes.get_unit_for(size),
                (1073741824.0, "GiB")
            );
            assert_eq!(
                BandwidthUnitFamily::BinBits.get_unit_for(size),
                (134217728.0, "Gib")
            );
            assert_eq!(
                BandwidthUnitFamily::SiBytes.get_unit_for(size),
                (1000000000.0, "GB")
            );
            assert_eq!(
                BandwidthUnitFamily::SiBits.get_unit_for(size),
                (125000000.0, "Gb")
            );
        }
        {
            let size = 1024. * 1024. * 1024. * 1024.;
            assert_eq!(
                BandwidthUnitFamily::BinBytes.get_unit_for(size),
                (1099511627776.0, "TiB")
            );
            assert_eq!(
                BandwidthUnitFamily::BinBits.get_unit_for(size),
                (137438953472.0, "Tib")
            );
            assert_eq!(
                BandwidthUnitFamily::SiBytes.get_unit_for(size),
                (1000000000000.0, "TB")
            );
            assert_eq!(
                BandwidthUnitFamily::SiBits.get_unit_for(size),
                (125000000000.0, "Tb")
            );
        }
    }
}

[cyqsimon]

Ah okay. Yeah a unit test will do. I was overcomplicating the situation thinking I need an integration test.

I used some itertools magic to test a wider variety of values. Now I can finally see the appeal of cargo insta 😅.

---

the next 2 k are lowercase
should they be uppercase ?
they are uppercase on the next units (M G T)

Nope. The k prefix is deliberately lowercase as per ISO 80000.

[cyqsimon]

Also I took a look at the test cases < 1024; I don't really see a problem? Can you please help me verify? Thanks.

[sigmaSd]

Ah I see, I was misunderstanding what get_unit_for does, so there is no problem indeed. Cool test btw

[cyqsimon]

Okay then. Let's get this merged!