Added corfu-candidate-overlay-complete-at-point function

corfu-candidate-overlay.el

@@ -5,7 +5,7 @@
 ;; Author: Adam Kruszewski <adam@kruszewski.name>
 ;; Maintainer: Adam Kruszewski <adam@kruszewski.name>
 ;; Created: 2023
-;; Version: 1.3
+;; Version: 1.4
 ;; Package-Requires: ((emacs "28.1") (corfu "0.36"))
 ;; Homepage: https://code.bsdgeek.org/adam/corfu-candidate-overlay/
 
@@ -232,6 +232,20 @@ Otherwise the overlay can influence movement commands (i.e. the cursor is
                       is-delete-command))))
           (corfu-candidate-overlay--hide)))))
 
+(defun corfu-candidate-overlay-at-word-boundary-p ()
+  "Return non-nil when cursor is at the word boundary for completion purposes.
+Or nil otherwise."
+  (let ((next-char (char-after)))
+    (or (not next-char) ;; end of file
+        ;; one of whitespace, quoting character, punctuation,
+        ;; closing bracket, etc is next.
+        ;; When those characters follow next completion won't trigger
+        ;; either-way: ' = * - + / ~ _ (have not investigated further),
+        ;; so they are not in the list.
+        (memq next-char '(?\s ?\t ?\r ?\n
+                              ?\" ?\` ?\) ?\] ?\>
+                              ?\. ?\, ?\: ?\;)))))
+
 (defun corfu-candidate-overlay--post-command ()
   "Post command hook to update candidate overlay.
 Update happens when the user types character and the cursor is at
@@ -246,8 +260,8 @@ the end of word."
             (corfu--match-symbol-p corfu-auto-commands this-command))
            (is-delete-command
             (corfu--match-symbol-p corfu-candidate-overlay-auto-commands this-command)))
-        ;; short-circuit conditions -- the earlier we return if don't need to do
+      ;; short-circuit conditions -- the earlier we return, if don't need to do
-        ;; anything the better.
+      ;; anything, the better.
       (if (and
            ;; we are not in minibuffer, as it looks awkward.
            (not (minibuffer-window-active-p (selected-window)))
@@ -259,24 +273,16 @@ the end of word."
                  (= corfu-candidate-overlay--last-point (point))))
            (or  ;; do not update if it is not one of the insert or delete commands.
             is-insert-command
-              is-delete-command))
+            is-delete-command)
-            ;; now we check additional short-circuit conditions, but those operate on
+           ;; check whether we are at word boundardy.
-            ;; next character.
+           (corfu-candidate-overlay-at-word-boundary-p))
-            (let ((next-char (char-after)))
+          ;; ...when main compound conditions is true clause...
-              (when (or  ;; do not update if we are not at the end of the word.
+          (progn
-                     (not next-char) ;; end of file
-                     ;; one of whitespace, quoting character, punctuation,
-                     ;; closing bracket, etc is next.
-                     ;; When those characters follow next completion won't trigger
-                     ;; either-way: ' = * - + / ~ _ (have not investigated further)
-                     (memq next-char '(?\s ?\t ?\r ?\n
-                                           ?\" ?\` ?\) ?\] ?\>
-                                           ?\. ?\, ?\: ?\;)))
             ;; When the completion backend is SLOW, i.e. like every LSP client,
             ;; then the overlay will often not update and will interfere with the typing.
             ;; That's why we operate on stored prefix and candidate giving an illusion
             ;; of updating the overlay -- but using the previous auto suggestion candidate.
-                (when corfu-candidate-overlay--overlay ;; need overlay active
+            (when corfu-candidate-overlay--overlay
               (let* ((candidate
                       (corfu-candidate-overlay--get-overlay-property  'corfu-candidate))
                      (prefix
@@ -323,10 +329,22 @@ the end of word."
             ;; the corfu-candidate-overlay--show CAN be interrupted, that's why
             ;; we did the shuffling above.
             (setq corfu-candidate-overlay--last-point (point))
-                (corfu-candidate-overlay--show)))
+            (corfu-candidate-overlay--show))
-          ;; or hide the overlay if the conditions to show the overlay where not met.
+        ;; ...when main compound conditions is false clause...
+        ;; so hide the overlay if the conditions to show the overlay where not met.
         (corfu-candidate-overlay--hide)))))
 
+;;;###autoload
+(defun corfu-candidate-overlay-complete-at-point ()
+  "Insert the first completion candidate shown in the overlay."
+  (interactive)
+  (when
+      (and corfu-candidate-overlay--overlay
+           (overlayp corfu-candidate-overlay--overlay)
+           (corfu-candidate-overlay-at-word-boundary-p))
+
+    (insert (corfu-candidate-overlay--get-overlay-property 'corfu-candidate))))
+
 ;;;###autoload
 (define-minor-mode corfu-candidate-overlay-mode
   "Show first candidate in an overlay while typing."

readme.org

@@ -12,6 +12,8 @@ Overlay showing auto-completion candidate when there is only one available (so i
 [[./readme-images/corfu-candidate-overlay-one.png]]
 
 It show the first auto-suggestion from [[https://github.com/minad/corfu][corfu]] and when there is only one it will show it underlined (face attributes can be configured). In case of many suggestions available, invoking =completion-at-point= will open the corfu popup menu to choose from, in case of single completion available (i.e. underlined) it will get auto-completed seeing the menu when invoked =completion-at-point=.
+
+Package exposes also one interactive function =corfu-candidate-overlay-complete-at-point= which you can bind to a key combination. Invoking the function will complete the exact candidate overlay is currently showing[fn:4] (i.e. it will not show corfu's popup even if there are more candidates present, just complete what you see).
 ** Motivation
 Similarly to Michell Hashimoto[fn:1] of HashiCorp fame, I like my editor to do less than more. I'm not as ascetic though ;-) From time to time I do use the auto-suggestion menu of [[https://github.com/minad/corfu][corfu]], especially when I forget the exact wording of a function. I do however trigger the auto-suggestion popup manually.
 
@@ -40,8 +42,11 @@ When using slow or cpu-heavy corfu backends (e.g. [[https://github.com/minad/cap
     ;; enable corfu-candidate-overlay mode globally
     ;; this relies on having corfu-auto set to nil
     (corfu-candidate-overlay-mode +1)
-    ;; bind Ctr + TAB to trigger the completion popup of corfu
+    ;; bind Ctrl + TAB to trigger the completion popup of corfu
-    (global-set-key (kbd "C-<tab>") 'completion-at-point))
+    (global-set-key (kbd "C-<tab>") 'completion-at-point)
+    ;; bind Ctrl + Shift + Tab to trigger completion of the first candidate
+    ;; (keybing <iso-lefttab> may not work for your keyboard model)
+    (global-set-key (kbd "C-<iso-lefttab>") 'corfu-candidate-overlay-complete-at-point))
 #+end_src
 ** Customization
 Faces available for customization:
@@ -72,6 +77,7 @@ Issue reports, questions, comments and code patches are welcome -- you can send
 If you haven't sent code patches via e-mail yet and would like to learn how to work with an e-mail based workflow, you can read more at [[https://git-scm.com/docs/git-format-patch][git format-patch]] man page or at [[https://git-send-email.io/][git-send-email.io]].
 
 * Footnotes
+[fn:4] Thanks to [[https://github.com/terlar][Terje Larsen]] for suggestion!
 
 [fn:1] See video cast:
   [[https://www.youtube.com/watch?v=rysgxl35EGc][Worst Practices in Software Development: Mitchell Hashimoto uses a simple code editor]].