The last commit tries to simplify the logic for progress call backs. I couldn't get it to work with references, so I'm boxing things now. If this isn't acceptable I'll revert back to using if let Some() = progress inside the two flash targets.

Eh, I went a different way. I removed the optionality and then added an empty impl as the "do nothing" value.

I think this is looking pretty good in general, thanks for this. We had discussed using the null object pattern like this when we originally added the callbacks, don't recall why we didn't end up doing it, but I think it's fine.

One nit, I don't love the name EmptyProgressCallbacks, empty doesn't seem like the right word here. With that said, not quite sure what it should be called, so I guess I don't really have any right to say anything 😅

There is one comment from a user which may need addressing still, haven't read through it yet honestly.

I think this is looking pretty good in general, thanks for this. We had discussed using the null object pattern like this when we originally added the callbacks, don't recall why we didn't end up doing it, but I think it's fine.

I really did try to make it work nicely with Option<&mut dyn ProgressCallbacks> but after 45mins I gave up 😅.

One nit, I don't love the name EmptyProgressCallbacks, empty doesn't seem like the right word here. With that said, not quite sure what it should be called, so I guess I don't really have any right to say anything 😅

Would DefaultProgressCallbacks be better? I'll change it to that, let me know what you think.

There is one comment from a user which may need addressing still, haven't read through it yet honestly.

Thanks, I missed the skip flag part, that's a good idea, I'll add it.