vertico--format-candidate adds an extra whitespace

[manuel-uberti]

Hi,

first of all, this is a minor glitch so feel free to ignore the problem. Since I do not use marginalia, I customize vertico-current with :extend set to nil:

(set-face-attribute 'vertico-current nil :extend nil)

However, it seems like vertico--format-candidate adds a whitespace at the end of the current selected candidate:

If I override vertico--format-candidate with the following advice:

(define-advice vertico--format-candidate
    (:override (cand prefix suffix index _start) mu-vertico--format-candidate)
  "Format CAND given PREFIX, SUFFIX and INDEX."
  (setq cand (vertico--display-string (concat prefix cand suffix "\n")))
  (when (= index vertico--index)
    (add-face-text-property 0 (1- (length cand)) 'vertico-current 'append cand))
  cand)

The whitespace is removed:

Is it something vertico should take into account or should I just use the advice for this specific use-case? I wouldn't want you to add useless complexity and hacks to vertico just for this.

[minad]

I see. I think for extend to work we also have to fontify the \n. Therefore we cannot fix this as you proposed.

We could detect if extend is set to nil, but this is a special configuration which is neither common nor recommended.

Why do you dislike extend? In particular with long candidates or Marginalia I prefer the extended highlight.

[manuel-uberti]

To me the highlight makes sense only where there is something to place it upon. Without Marginalia, I see long highlights extended horizontally across the screen with little content in them.

I see your point though, I'll keep the advice in my configuration then.