Using relative height PR is incomplete

[bestlem]

Describe your issue

The change in 11a022f changed the handling for the default font but it also should handle fixed-pitch.

I have doom-font and doom-variable font of different sizes. When I use org-mode and source code blocks the fixed font in the blocks has the same font size height as the variable font instead of using the font size specified in doom-font.

The comment for the setting of doom-font to begin with includes

(defcustom doom-font nil
  "The default font to use.
Must be a `font-spec', a font object, an XFT font string, or an XLFD string.

This affects the `default' and `fixed-pitch' faces.

...

Thus default and fixed pitch should be treated the same.

I have a patch that seems to fix this

@@ -639,7 +639,8 @@ windows, switch to `doom-fallback-buffer'. Otherwise, delegate to original
                   ;; only adjusts `doom-font' for the default face, then calls
                   ;; `doom-init-fonts-h' to propagate).  Convert now, before
                   ;; `custom-push-theme' snapshots the value.
-                  (unless (eq face 'default)
+                  (unless (or (eq face 'default)
+                              (eq face 'fixed-pitch))
                     (let ((default-height (face-attribute 'default :height frame)))
                       (when (and (integerp default-height) (> default-height 0))

Steps to reproduce

Set doom-font

(setq doom-font (font-spec :family "Jetbrains Mono Slashed" :size 14)
      doom-variable-pitch-font (font-spec :family "Georgia" :size 18)
    )

Put (variable-pitch-mode 1) in org-mode-hook
Then check the font definition for a character in a source code block.

System information

https://pastebin.com/1SDeJnL1

Disclosures

• This issue was written with/by AI.

[hlissner]

Can you provide screenshots? I cannot reproduce any odd behavior.

Put (variable-pitch-mode 1) in org-mode-hook
Then check the font definition for a character in a source code block.

Did you mean mixed-pitch-mode? variable-pitch-mode won't use the fixed-pitch face anywhere unless your theme (or you) explicitly instruct it to do so. What theme are you using, anyhow?

[bestlem]

The theme I am using is via (setq doom-theme 'modus-vivendi-tinted)

I also set (setopt modus-themes-mixed-fonts t) This then sets an inherit from fixed-pitch,
This defines org-block as based on modus-themes-fixed-pitch which is based on fixed-pitch.

I am using variable-pitch-mode - In my config I have the comment that mixed-pitch-mode does not work if I resize ie zoom the buffer in or out, but that comment is several months old and I do not remember the full issue.

[hlissner]

Whoa. Modus is doing a lot of fixed-pitch/variable-pitch hackery... Afraid there's little I can do here but suggest you disable modus-themes-mixed-fonts, perhaps figure out why mixed-pitch-mode isn't working for you with it off (I generally have no issues with any of these modes with other themes).

;;; add to $DOOMDIR/config.el
(with-eval-after-load 'modus-themes
  (setq modus-themes-mixed-fonts nil))

Emacs' API for remapping faces is notoriously brittle, and there are a multitude of ways that themes can jam a wrench into it, one of those ways being inheriting faces from default, fixed-pitch, and variable-pitch explicitly (as modus-themes-mixed-fonts will, breaking variable-pitch-mode, mixed-pitch-mode, and text-scale in odd ways) or giving them a hardcoded :height (like modus-themes-headings does, breaking text-scale or doom/increase-font-size).

There is no accommodating all possible cases. There are themes that do even stranger things (not even mentioning what users can do themselves with a creative custom-set-faces call). I'm realizing now that @agzam's fix in #8733 only fixed their particular issue (causing yours), and your patch will only fix yours (breaking theirs). So #8733 was merged in error. I'll revert it soon.

---

@agzam Can you tell me what theme you're using?

[hlissner]

perhaps figure out why mixed-pitch-mode isn't working for you with it off (I generally have no issues with any of these modes with other themes).

Actually, I know why it doesn't work for you: modus is inheriting a ton of faces (including org faces) from default, explicitly, so they explicitly inherit the hardcoded font-size of default, which overrules mixed-pitch.