breaking API change in 0.4.4+ - added variant to public + not-non_exhaustive enum

[decathorpe]

This PR added a new variant to an enum that is not marked as non-exhaustive: #12

cargo semver-checks confirms that this is a breaking change, but it was released as a semver-compatoble patch-release:

$ cargo semver-checks --baseline-version 0.4.3
(...)

--- failure enum_variant_added: enum variant added on exhaustive enum ---

Description:
A publicly-visible enum without #[non_exhaustive] has a new variant.
        ref: https://doc.rust-lang.org/cargo/reference/semver.html#enum-variant-new
       impl: https://github.com/obi1kenobi/cargo-semver-checks/tree/v0.39.0/src/lints/enum_variant_added.ron

Failed in:
  variant NotifyState:MonotonicUsec in src/lib.rs:80

     Summary semver requires new major version: 1 major and 0 minor checks failed

[lnicola]

Thanks, I'll try to put out a new version "soon" (though there are some other pending breaking changes I have to review).

May I ask how you found this? I hope nobody tried to match on that enum.

[decathorpe]

How I found it? I did my due diligence as package maintainer when I looked at updating the Fedora Linux package for this crate to the latest version. 😉 (In all fairness, I might not have caught this if I didn't actually look at the diff between 0.4.3 and 0.4.5 and noticed that a pub enum had variant changes, so it was kind of lucky.)

[lnicola]

Oh wow, added 4 years ago, I use Fedora and I had no idea.

Well, I guess yanking now wouldn't help you too much and would just annoy the users.

[decathorpe]

Yeah, probably. If you think it's unlikely that anybody actually exhaustively matched against that enum, then publishing the current state (plus whatever other breaking changes you have lined up) as 0.5.0 should be fine (plus adding a warning to the release notes maybe) :)