Primary cursor colors by mode

[gibbz00]

This PR is the result of a discussion held in #4298. It's an alternative solution to #4298 and #2366, which in turn closes the issues in #1833 and #1337.

In short; it adds the possibility to set primary and non-primary (secondary) cursor colors for a given mode. Compared to the other presented solutions:

• The source change is smaller and IMO cleaner.
• Adds the possibility to set a primary for normal mode and a fallback for the other modes.
• Does not introduce any breaking changes to the themes and their current behavior.
• Is consistent with other fallback behavior for themes.

Example of something that was previously not possible to do:

https://imgur.com/a/JHxYuJm

Diagram for fallback behavior:

https://imgur.com/a/Kds3606

[the-mikedavis]

Ah this is much simpler 😀

#4596 is a bit more complicated because it adds an option. We wanted a similar option for color-modes since a theme could define color-modes and you might not want to see them. I suppose that could be added to this but I don't think it's necessary since theme inheritance was merged (#3067), so let's not add it for now.

[ivenw]

I can get behind this simpler implementation over #4596. Theme inheritance now means that we don't need the setting toggle (and probably should remove toggles for other theme related settings that can be resolved on the theme level).

I only have two remarks/concerns:

1. Do we need any form of .normal? Aren't the only special cases of cursor theming .insert and .select? Whatever color the cursor has in NORMAL mode would already be set by the base cursor color of the respective scope.
2. I still prefer the use of .secondary over .primary (which is I think where most of the complexity of my proposed change came from). To me at least it makes more sense that ui.cursor sets the "primary" scope and that the special case of wanting to have a different secondary cursor color is handled by cursor.secondary. The main problem that exists now with .primary (In this PR but also master) is that in its absence in a theme,ui.cursor sets the "primary" cursor color, whereas in the presence of cursor.primary, cursor now sets the "secondary" cursor color now.

Granted, point 2 is not a major issue but from a logical flow, if we consider the evolution of a theme in its development, it's a bit awkward.

[gibbz00]

Hi,

As for the first concern; The source code has to explicitly set the cursor of normal mode anyway (see the diff in this PR), so adding the .normal option costs nothing more than one or two word replacements.

The added benefit to this would for example be if a user wants to change the cursor for normal mode only; all he/she would have to do is change add a .normal line in their theme override, as opposed to adding two lines (insert and select) to indirectly change the normal cursor only. (Or possibly even more lines if things are added in the future.) The same thing could be said for theme developers.

Basically, if something wants to be special, make it special. Rather than changing the rest to make it distinguishable.

On the second note, I do agree with you that it makes in a way sense to have ui.cursor as the primary, since “it comes first”. But my understanding is that there is no such thing as “secondary” cursors in Helix. It's either cursor or primary.
The word “secondary” is not mentioned even once in the documentation nor in the tutor. Adding the concept “secondary” makes the concept “primary” redundant/obsolete, they oppose each other but explain the same thing.

So:
Do we really want to flip this mental model for a single theme setting?
Do we suddenly want to become inconsistent with which mental model we use?
Is it worth flipping ALL mentions of primary to make the presented mental model consistent with a theme setting?

My answer was no to all three, and I would even argue that such changes would make things even more awkward.
I therefore also have a hard time believing that the setting will be revised into a “secondary” going forward.

Hope this answered your questions. I do like the idea though about removing the other theme setting toggles.

All the best :)

[ivenw]

Good points. Your response to 1. makes me withdraw that remark.

When it comes to 2. I suppose it's what it is. To my eyes it looked like the current mental model came by chance and things being added on other things rather that it was intended to be this way. That of course is entirely an outside perspective.

Overall I do agree it's a minor thing and may not get the momentum to change it (and may not deserve that momentum to begin with)

I'd be happy to see this PR accepted as it would close a problem brought up in many issues and PRs over time, while only introducing a minor change at the same time.

[gibbz00]

@archseer @the-mikedavis what's up with this PR not getting merged? Is there anything I can do on my end?

[David-Else]

@gibbz00 Hi, I am trying to add this feature to dark_plus https://github.com/helix-editor/helix/blob/master/runtime/themes/dark_plus.toml and have run into a problem/possible bug. I am trying to get the insert and select cursor to mirror the color in the statusline. I added:

"ui.cursor.primary.normal" = { fg = "cursor", modifiers = ["reversed"] }
"ui.cursor.primary.insert" = { fg = "yellow", modifiers = ["reversed"] }
"ui.cursor.primary.select" = { fg = "magenta", modifiers = ["reversed"] }

It works, but if I press A to add to the end of the line, the cursor does not change color as it changes into insert mode, but the statusline color does. Can you comment? This is my first attempt to mod a theme, I am not sure if I am doing it right. The entire ui.cursor block was:

"ui.cursor" = { fg = "cursor", modifiers = ["reversed"] }
"ui.cursor.primary" = { fg = "cursor", modifiers = ["reversed"] }
"ui.cursor.match" = { bg = "#3a3d41", modifiers = ["underlined"] }

and is now:

"ui.cursor" = { fg = "cursor", modifiers = ["reversed"] }
"ui.cursor.primary.normal" = { fg = "cursor", modifiers = ["reversed"] }
"ui.cursor.primary.insert" = { fg = "yellow", modifiers = ["reversed"] }
"ui.cursor.primary.select" = { fg = "magenta", modifiers = ["reversed"] }
"ui.cursor.primary" = { fg = "cursor", modifiers = ["reversed"] }
"ui.cursor.match" = { bg = "#3a3d41", modifiers = ["underlined"] }

[gibbz00]

@David-Else apologies for the late reply. We're you able to resolve the issue or does it still persist?

[David-Else]

@gibbz00 I am afraid it still persists. The cursor does not change colour when it is over a space or invisible line end character. When I said "if I press A to add to the end of the line" I was just seeing the affect of the cursor being on an invisible line end character.

Can you help?

[gibbz00]

Bummer, but I'll see what I can do :) What I'm using in ayu_evolve:

"ui.cursor" = { fg = "dark_gray", bg = "light_gray" }
"ui.cursor.primary" = { fg = "dark_gray", bg = "orange" }
"ui.cursor.primary.select" = { fg = "dark_gray", bg = "magenta" }
"ui.cursor.primary.insert" = { fg = "dark_gray", bg = "green" }

Have you tried removing the "reversed" modifier and setting the cursor color using the background? Append to end of line works on my end.