completion: add functions to jump between minibuffer and completions

* common.el (durand-completion-goto-minibuffer): Go to the
  *Completions* buffer or the minibuffer, depending on whether we are
  *in the minibuffer or the *Completions* buffer and the target buffer
  *exists.

* completion-conf.el (minibuffer-local-completion-map)
(completion-list-mode-map): Bind the function in the right map.

2 files changed, 36 insertions, 0 deletions

diff --git a/common.el b/common.el
index 7da6129..aa90a88 100644
--- a/common.el
+++ b/common.el
@@ -156,6 +156,40 @@ ARG means do this command ARG times."
             ((< arg 0)
              (goto-char (point-max))))))))
 
+(defun durand-completion-goto-minibuffer ()
+  "Go to the minibuffer."
+  (interactive)
+  (let ((active-minibuffer-window (active-minibuffer-window))
+        (completion-windows
+         (delq nil
+               (mapcar
+                (lambda (w)
+                  (and (consp
+                        (delq nil
+                              (mapcar
+                               (lambda (name)
+                                 (string-match-p
+                                  name
+                                  (buffer-name (window-buffer w))))
+                               durand-completion-buffer-names)))
+                       w))
+                (window-list nil 'nomini))))
+        (in-completion-p (consp
+                          (delq nil
+                                (mapcar
+                                 (lambda (name)
+                                   (string-equal name (buffer-name)))
+                                 durand-completion-buffer-names))))
+        (in-minibuffer-p
+         (minibuffer-window-active-p (selected-window))))
+    (cond
+     ((and active-minibuffer-window
+           (not in-minibuffer-p))
+      (select-window active-minibuffer-window))
+     ((and (consp completion-windows)
+           (not in-completion-p))
+      (select-window (car completion-windows))))))
+
 ;; This can be optimized by not duplicating an element on the stack.
 
 ;;;###autoload
diff --git a/completion-conf.el b/completion-conf.el
index b47520d..7885943 100644
--- a/completion-conf.el
+++ b/completion-conf.el
@@ -51,11 +51,13 @@
 (define-key minibuffer-local-completion-map (vector ?\C-p) #'durand-embark-scroll-up-or-go-to-completions)
 (define-key minibuffer-local-completion-map (vector ?\s-v) #'durand-completion-toggle-display)
 (define-key minibuffer-local-completion-map (vector 32) nil)
+(define-key minibuffer-local-completion-map (vector ?\M-o) #'durand-completion-goto-minibuffer)
 (define-key minibuffer-local-must-match-map (vector 32) nil)
 (define-key completion-list-mode-map (vector 'down) #'durand-completion-scroll-down-or-go-to-minibuffer)
 (define-key completion-list-mode-map (vector 'up) #'durand-completion-scroll-up-or-go-to-minibuffer)
 (define-key completion-list-mode-map (vector ?\C-n) #'durand-completion-scroll-down-or-go-to-minibuffer)
 (define-key completion-list-mode-map (vector ?\C-p) #'durand-completion-scroll-up-or-go-to-minibuffer)
+(define-key completion-list-mode-map (vector ?\M-o) #'durand-completion-goto-minibuffer)
 
 ;;; New behaviours of emacs 29 make the default completion list more useful now