vertico.el - VERTical Interactive COmpletion

Introduction

This package provides a minimalistic vertical completion UI, which is based on the default completion system. By reusing the default system, Vertico achieves full compatibility with built-in Emacs commands and completion tables. Vertico is pretty bare-bone and only provides a minimal set of commands. The code base is less than 500 lines of code. Additional optional enhancements can be provided externally by complementary packages.

Features

• Vertical display with arrow key navigation
• Shows the index of the current candidate and the total number of candidates
• The current candidate is inserted with TAB and selected with RET
• Non-existing candidates are entered by moving the point to the prompt line
• Candidates are sorted by history, string length and alphabetically
• Long candidates with newlines are formatted to take up less space
• Support for annotation-function, affixation-function and x-group-function

Configuration

Vertico is available from GNU ELPA, such that it can be installed directly via package-install. After installation, the global minor mode can be enabled with M-x vertico-mode. In order to configure Vertico and other packages in your init.el, you may want to use use-package. Here is an example configuration:

;; Enable vertico
(use-package vertico
  :init
  (vertico-mode))

;; Use the `orderless' completion style.
;; Enable `partial-completion' for files to allow path expansion.
;; You may prefer to use `initials' instead of `partial-completion'.
(use-package orderless
  :init
  (setq completion-styles '(orderless)
        completion-category-defaults nil
        completion-category-overrides '((file (styles . (partial-completion))))))

;; A few more useful configurations...
(use-package emacs
  :init
  ;; Add prompt indicator to `completing-read-multiple'.
  (defun crm-indicator (args)
    (cons (concat "[CRM] " (car args)) (cdr args)))
  (advice-add #'completing-read-multiple :filter-args #'crm-indicator)

  ;; Grow and shrink minibuffer
  ;;(setq resize-mini-windows t)

  ;; Do not allow the cursor in the minibuffer prompt
  (setq minibuffer-prompt-properties
        '(read-only t cursor-intangible t face minibuffer-prompt))
  (add-hook 'minibuffer-setup-hook #'cursor-intangible-mode)

  ;; Enable recursive minibuffers
  (setq enable-recursive-minibuffers t))

Keymap

Vertico defines its own local keymap in the minibuffer which is derived from minibuffer-local-map. The keymap mostly keeps the fundamental-mode keybindings intact, but rebinds a few commands. Note in particular the binding of TAB to vertico-insert and the bindings of vertico-exit/exit-input.

• beginning-of-buffer, minibuffer-beginning-of-buffer -> vertico-beginning-of-buffer
• end-of-buffer -> vertico-end-of-buffer
• scroll-down-command -> vertico-scroll-down
• scroll-up-command -> vertico-scroll-up
• next-line, next-line-or-history-element -> vertico-next
• previous-line, previous-line-or-history-element -> vertico-previous
• exit-minibuffer -> vertico-exit
• kill-ring-save -> vertico-save
• <C-return> -> vertico-exit-input
• TAB -> vertico-insert

Note that none of the bindings of the minibuffer-local-completion-map are bound by default. If you prefer to have the default completion commands a key press away you may want to add a few bindings. Then the default completion commands will work as usual. For example you can use M-TAB to cycle between candidates if you have set completion-cycle-threshold.

(define-key vertico-map "?" #'minibuffer-completion-help)
(define-key vertico-map "\M-\r" #'minibuffer-force-complete-and-exit)
(define-key vertico-map "\M-\t" #'minibuffer-complete)

If Vertico is active, you may want to disable the automatic *Completions* buffer by setting completion-auto-help to nil and make TAB-completion less noisy by setting completion-show-inline-help to nil.

(advice-add #'vertico--setup :after
            (lambda (&rest _)
              (setq-local completion-auto-help nil
                          completion-show-inline-help nil)))

Complementary packages

Vertico works well together with a few complementary packages, which enrich the completion UI. These packages are fully supported:

• Marginalia: Rich annotations in the minibuffer
• Consult: Many useful search and navigation commands
• Embark: Minibuffer actions and context menu
• Orderless: Advanced completion style

Alternatives

There are many alternative completion UIs, each UI with its own advantages and disadvantages. The Selectrum readme provides an extensive comparison of many available completion systems from the perspective of Selectrum.

Vertico aims to be fully compliant with all Emacs commands and achieves that with a minimal code base, relying purely on completing-read while avoiding to invent its own APIs. Inventing a custom API as Helm or Ivy is explicitly avoided in order to increase flexibility and package reuse.

Since Vertico only provides the UI, you may want to combine it with some of the complementary packages, to give a full-featured completion experience similar to Ivy. Vertico is targeted at users interested in crafting their Emacs precisely to their liking - completion plays an integral part in how the users interacts with Emacs. There are at least two other interactive completion UIs, which follow a similar philosophy:

• Selectrum: If you are looking for a less minimalistic and more full-featured (but also more complex) package, you may be interested in Selectrum, which provides a similar UI as Vertico. Additionally Selectrum supports Avy-style quick keys, a horizontal display and a configurable buffer display.
• Icomplete-vertical: This package enhances the Emacs builtin Icomplete with a vertical display. In contrast to Vertico, the candidates are rotated such that the current candidate always appears at the top. From my perspective, candidate rotation feels a bit less intuitive than the UI provided by Vertico or Selectrum.