Function: icomplete--render-vertical

icomplete--render-vertical is a byte-compiled function defined in icomplete.el.gz.

Signature

(icomplete--render-vertical COMPS MD)

Source Code

;; Defined in /usr/src/emacs/lisp/icomplete.el.gz
(cl-defun icomplete--render-vertical
    (comps md &aux scroll-above scroll-below
           (total-space ; number of mini-window lines available
            (1- (min
                 icomplete-prospects-height
                 (truncate (max-mini-window-lines) 1)))))
  ;; Welcome to loopapalooza!
  ;;
  ;; First, be mindful of `icomplete-scroll' and manual scrolls.  If
  ;; `icomplete--scrolled-completions' and `icomplete--scrolled-past'
  ;; are:
  ;;
  ;; - both nil, there is no manual scroll;
  ;; - both non-nil, there is a healthy manual scroll that doesn't need
  ;;   to be readjusted (user just moved around the minibuffer, for
  ;;   example)l
  ;; - non-nil and nil, respectively, a refiltering took place and we
  ;;   may need to readjust them to the new filtered `comps'.
  (when (and icomplete-scroll
             icomplete--scrolled-completions
             (null icomplete--scrolled-past))
    (cl-loop with preds
             for (comp . rest) on comps
             when (equal comp (car icomplete--scrolled-completions))
             do
             (setq icomplete--scrolled-past preds
                   comps (cons comp rest))
             (completion--cache-all-sorted-completions
              (icomplete--field-beg)
              (icomplete--field-end)
              comps)
             and return nil
             do (push comp preds)
             finally (setq icomplete--scrolled-completions nil)))
  ;; Then, in this pretty ugly loop, collect completions to display
  ;; above and below the selected one, considering scrolling
  ;; positions.
  (cl-loop with preds = icomplete--scrolled-past
           with succs = (cdr comps)
           with space-above = (- total-space
                                 1
                                 (cl-loop for (_ . r) on comps
                                          repeat (truncate total-space 2)
                                          while (listp r)
                                          count 1))
           repeat total-space
           for neighbor = nil
           if (and preds (> space-above 0)) do
           (push (setq neighbor (pop preds)) scroll-above)
           (cl-decf space-above)
           else if (consp succs) collect
           (setq neighbor (pop succs)) into scroll-below-aux
           while neighbor
           finally (setq scroll-below scroll-below-aux))
  ;; Halfway there...
  (let* ((selected (propertize (car comps) 'icomplete-selected t))
         (chosen (append scroll-above (list selected) scroll-below))
         (tuples (icomplete--augment md chosen))
         max-prefix-len max-comp-len lines nsections)
    (add-face-text-property 0 (length selected)
                            'icomplete-selected-match 'append selected)
    ;; Figure out parameters for horizontal spacing
    (cl-loop
     for (comp prefix) in tuples
     maximizing (length prefix) into max-prefix-len-aux
     maximizing (length comp) into max-comp-len-aux
     finally (setq max-prefix-len max-prefix-len-aux
                   max-comp-len max-comp-len-aux))
    ;; Serialize completions and section titles into a list
    ;; of lines to render
    (cl-loop
     for (comp prefix suffix section) in tuples
     when section
     collect (propertize section 'face 'icomplete-section) into lines-aux
     and count 1 into nsections-aux
     when (get-text-property 0 'icomplete-selected comp)
     do (add-face-text-property 0 (length comp)
                                'icomplete-selected-match 'append comp)
     collect (concat prefix
                     (make-string (- max-prefix-len (length prefix)) ? )
                     (completion-lazy-hilit comp)
                     (make-string (- max-comp-len (length comp)) ? )
                     suffix)
     into lines-aux
     finally (setq lines lines-aux
                   nsections nsections-aux))
    ;; Kick out some lines from the beginning due to extra sections.
    ;; This hopes to keep the selected entry more or less in the
    ;; middle of the dropdown-like widget when `icomplete-scroll' is
    ;; t.  Funky, but at least I didn't use `cl-loop'
    (setq lines
          (nthcdr
           (cond ((<= (length lines) total-space) 0)
                 ((> (length scroll-above) (length scroll-below)) nsections)
                 (t (min (ceiling nsections 2) (length scroll-above))))
           lines))
    ;; At long last, render final string return value.  This may still
    ;; kick out lines at the end.
    (concat " \n"
            (cl-loop for l in lines repeat total-space concat l concat "\n"))))