Minibuffer frame for Nano Emacs

nano-minibuffer.el

;; Nicolas .P Rougier emacs configuration - mini-frame configuration
;; ---------------------------------------------------------------------
(require 'vertico)
(require 'marginalia)
(require 'mini-frame)

(defun minibuffer-setup ()

  ;; This prevents the header line to spill over second line
  (let ((inhibit-message t))
    (toggle-truncate-lines 1))

  (setq enable-recursive-minibuffers t)
  
  ;; This allows to have a consistent full width (fake) header like
  (setq display-table (make-display-table))
  (set-display-table-slot display-table
                          'truncation (make-glyph-code ?\  'nano-subtle))
  (set-display-table-slot display-table
                          'wrap (make-glyph-code ?\  'nano-subtle))
  (setq buffer-display-table display-table)
  
  (cursor-intangible-mode)
  (face-remap-add-relative 'default :foreground "black")
  (face-remap-add-relative 'completions-first-difference :foreground "black")
  (let* ((left  (concat (propertize " "
                                    'face '(nano-subtle)
                                    'display '(raise +0.20))
                        (propertize " Minibuffer"
                                    'face 'nano-subtle)
                        (propertize " "
                                    'face 'nano-subtle
                                    'display '(raise -0.30))))
         (right (propertize "C-g: abort"
                            'face '(:inherit (nano-faded nano-subtle)
                                    :weight light)))
         (spacer (propertize (make-string (- (window-width)
                                             (length left)
                                             (length right)
                                             1) ?\ )
                             'face 'nano-subtle))
         (header (concat left spacer right " "))
         (overlay (make-overlay (+ (point-min) 0) (+ (point-min) 0))))
    (overlay-put overlay 'before-string
        (concat
         (propertize " " 'display header)
         "\n"
         ;; This provides a vertical gap (half a line) above the prompt.
         (propertize " " 'face `(:extend t)
                     'display '(raise .33)
                     'read-only t 'cursor-intangible t)))))

 (add-hook 'minibuffer-setup-hook #'minibuffer-setup)


;; (defun minibuffer-exit ())
;; (add-hook 'minibuffer-exit-hook #'minibuffer-exit)

;; Prefix/Affix the current candidate. From
;; https://github.com/minad/vertico/wiki#prefix-current-candidate-with-arrow
(defun minibuffer-format-candidate (orig cand prefix suffix index _start)
  (let ((prefix (if (= vertico--index index)
                    "  " "   "))) 
    (funcall orig cand prefix suffix index _start)))
  
(advice-add #'vertico--format-candidate
            :around #'minibuffer-format-candidate)

(with-eval-after-load 'vertico
  (setq completion-styles '(basic substring partial-completion flex))
  (setq vertico-count 10)
  (setq vertico-count-format nil)
  (setq vertico-grid-separator
        #("  |  " 2 3 (display (space :width (1))
                               face (:background "#ECEFF1"))))
  (define-key vertico-map (kbd "<backtab>") #'minibuffer-complete)
  (set-face-attribute 'vertico-current nil
                      :inherit '(nano-strong nano-subtle))
  (set-face-attribute 'completions-first-difference nil
                      :inherit '(nano-default))
  (set-face-attribute 'minibuffer-prompt nil
                      :inherit '(nano-default nano-strong))
  (setq minibuffer-prompt-properties
        '(read-only t cursor-intangible t face minibuffer-prompt))

  (defun vertico--prompt-selection ()
    "Highlight the prompt"
    (let ((inhibit-modification-hooks t))
      (set-text-properties (minibuffer-prompt-end) (point-max)
                           '(face (nano-strong nano-salient))))))

(with-eval-after-load 'marginalia
  (setq truncate-string-ellipsis "…")
  (setq marginalia--ellipsis "…")
  (setq marginalia-align 'right)
  (setq marginalia-align-offset -1))


(with-eval-after-load 'mini-frame
  (set-face-background 'child-frame-border (face-foreground 'nano-faded))
  (setq mini-frame-default-height vertico-count)
  (setq mini-frame-create-lazy t)
  (setq mini-frame-show-parameters 'mini-frame-dynamic-parameters)
  (setq mini-frame-ignore-commands
        '("edebug-eval-expression" debugger-eval-expression))
  (setq mini-frame-internal-border-color (face-foreground 'nano-subtle-i))
  ;; (setq mini-frame-resize 'grow-only) ;; -> buggy as of 01/05/2021
  ;; (setq mini-frame-resize 'not-set)
  ;; (setq mini-frame-resize nil)
  (setq mini-frame-resize t)
  (setq mini-frame-resize-min-height 3)

  
  (defun mini-frame-dynamic-parameters ()
    (let* ((edges       (window-pixel-edges))      ;; (left top right bottom)
           (body-edges  (window-body-pixel-edges)) ;; (left top right bottom)
           (left   (nth 0 edges))      ;; Take margins into account
           (top    (nth 1 edges)) ;; Drop header line
           (right  (nth 2 edges))      ;; Take margins into account
           (bottom (nth 3 body-edges)) ;; Drop header line
           (left   (if (eq left-fringe-width 0)
                       left
                     (- left (frame-parameter nil 'left-fringe))))
           (right  (nth 2 edges))
           (right  (if (eq right-fringe-width 0)
                       right
                     (+ right (frame-parameter nil 'right-fringe))))
           (fringe-left 0)
           (fringe-right 0)
           (border 1)
           ;; (width (- (frame-pixel-width) (* 2 (+ fringe border))))
           (width (- right left fringe-left fringe-right (* 0 border)))
           (y (- top border)))
    `((left . ,(- left border))
      (top . ,y)
      (alpha . 1.0)
      (width . (text-pixels . ,width))
      (left-fringe . ,fringe-left)
      (right-fringe . ,fringe-right)
      (child-frame-border-width . ,border)
      (internal-border-width . ,border)
      (foreground-color . ,(face-foreground 'nano-default))
      (background-color . ,(face-background 'highlight)))))
  )

(vertico-mode)
(marginalia-mode)
(mini-frame-mode t)

(provide 'nano-minibuffer)

Hello @minad,

Using your vertico-buffer.el and a whittled-down version of your code snippet above, I have a working vertico that displays in a true top side-window:

;;;; Vertico-buffer: show vertico in top side-window (Daniel Mendler)
;; https://github.com/minad/extensions/vertico-buffer.el

(use-package vertico-buffer
  :after (vertico)
  :demand t
  ;; https://gist.github.com/rougier/126e358464e12aa28fac5b4f3dd5eb9c?permalink_comment_id=4115602#gistcomment-4115602
  :init
  (defun my-vertico-buffer-setup ()
    ;; (dolist (win (get-buffer-window-list))
    ;;   (set-window-parameter win 'my-mini-window (window-minibuffer-p win)))
    (setq-local
     left-fringe-width 1
     right-fringe-width 1
     left-margin-width 1
     right-margin-width 1
     fringes-outside-margins t)
    ;; (dolist (win (get-buffer-window-list))
    ;;   (set-window-buffer win (current-buffer)))
    )
  :config
  (advice-add #'vertico-buffer--setup :after #'my-vertico-buffer-setup)
  (setq vertico-buffer-display-action
        '(display-buffer-in-side-window
          (window-height . 12)
          (side . top)))
  (vertico-buffer-mode +1)
  )

First: You may notice that I have commented out two dolist forms in your my-vertico-buffer-setup. In my setup, vertico-buffer still operates as expected. Can you explain under what circumstances these dolist forms are necessary?

Second: I have to say that, even though, as you know, this implementation handles only vertico, I absolutely love it.
This is precisely the minibuffer user experience I have craved for years. Earlier in this thread, you wrote:

My code snippet from above and the code from vertico-buffer could be generalized such that it applies to general minibuffer windows, not only to Vertico. This would then allow you to implement other non-disruptive actions in the same way.

Could I prevail upon you to provide such a generalized "code snippet"?