modifier "hidden" does not work

[chtenb]

Summary

The modifier "hidden" is documented here: https://docs.helix-editor.com/themes.html#modifiers
However, specifying it in a theme doesn't seem to do anything. Other modifiers work fine.
My terminal (wezterm) does support SGR 8.

Reproduction Steps

I tried this:

"ui.selection.primary" = { fg = "black", modifiers = ["hidden"] }

I expected this to happen:

Selected text rendered invisible.

Instead, this happened:

Selected text remained visible and got the fg color black

Helix log

No entries appear in the log while reproducing

Platform

Windows

Terminal Emulator

wezterm 20230712-072601-f4abf8fd

Helix Version

helix 23.05 (7f5940b)

[the-mikedavis]

As the docs say, these modifiers must be supported by your terminal emulator. We support a subset of SGR parameters via crossterm (see the crossterm docs). WezTerm implements a few SGR parameters not including hidden/conceal: https://github.com/wez/wezterm/blob/2c95b98447ac88e0327b84c725efc7b837bdbd75/termwiz/src/cell.rs#L268-L278.

Hidden is not widely supported so if we can't find any terminal emulators that support it, we could remove it from the docs.

[chtenb]

@the-mikedavis As far as I can tell, wezterm does support this code:

I don't completely understand the code at https://github.com/wez/wezterm/blob/main/termwiz/src/cell.rs#L268
because the numbers do not make sense to me, but I do see an "invisible" attribute, which is probably for the hidden/conceal code?

[the-mikedavis]

Ah whoops I see, the WezTerm SGR code is here instead: https://github.com/wez/wezterm/blob/99c9613966a73d5388344fd0df68d5977b493c7c/termwiz/src/escape/csi.rs#L2648, what I linked is unrelated.

[the-mikedavis]

Actually it looks like we just aren't mapping between the helix modifier and the crossterm attribute here. I've opened #8120 to fix it