feat: support "prio" priority value for gutter marks

[josh-nz]

This is my first pass at implementing #42.

Closes #42

I have not adjusted nor added any tests and therefore these might be broken. As per my previous pull request, my understanding of how to implement and run Neovim plugin tests is insufficient for me to be useful in this area.

[tris203]

Couple of points:

• In the default config we should add priorities, shorter movements should have higher priority. I would suggest, G = 10, gg = 9, { = 8, } = 8
  • This will break some tests but means we handle priority the same for gutters as we do for lines
  • We should add tests for priority replacing in gutter_hints_spec

If you need help with testing then more than happy to help guide you through it

But thanks for the PR @josh-nz. Its great to have help!

[tris203]

For some general help @josh-nz

The checks can be ran on your local machine by running make test

I really should write up a CONTRIBUTING.md

[josh-nz]

• In the default config we should add priorities, shorter movements should have higher priority. I would suggest, G = 10, gg = 9, { = 8, } = 8

This was addressed in commit 88ab881 I believe.

• We should add tests for priority replacing in gutter_hints_spec

Thanks for your help with the tests. I did figure out to run make to run the tests, and I was thinking of adding some notes about this and stylua to the readme (I was hoping to get away with manual formatting but my default nvim has different settings and I would sometimes forget to adjust them, and also pasting sometimes got it wrong, so I ended up downloading stylua). Would you prefer them in a separate MD file instead though?

Anything else that needs to be done?

[tris203]

I think this is ready to go, let me test it for a few days and then we will get it merged

Closes #42

[josh-nz]

One detail not documented is what happens if there is a conflict between hints with the same priority. In the case of the gutter hints, I believe it is first-in wins, where first-in is defined by the internal gutter hints Lua table ordering (ie, not config). Not sure how relevant this is to be noted anywhere, but something to consider. Similarly for the line hints.

[tris203]

One detail not documented is what happens if there is a conflict between hints with the same priority. In the case of the gutter hints, I believe it is first-in wins, where first-in is defined by the internal gutter hints Lua table ordering (ie, not config). Not sure how relevant this is to be noted anywhere, but something to consider. Similarly for the line hints.

@willothy what are your thoughts on this, I'm sort of thinking if you footgun yourself with your config raise an issue?

[josh-nz]

That's my preference. It's the simplest solution and doesn't add any additional code burden. Perhaps a quick note in the readme something to the effect of "make any hints that could appear in the same place as others have unique priorities to avoid conflicts"

[willothy]

Yeah, I agree. I don't think ordering of same-priority items is particularly important, and if someone does run into an issue they can ask about it.

[tris203]

Excellent, if you want to add a note to the README @josh-nz then we can get this merged

[josh-nz]

README updated.

[willothy]

I think @tris203 is asleep so I'm gonna go ahead and merge haha.

Thanks for all your work @josh-nz!