bug#41276: [PATCH v2 8/8] * lisp/epa.el (epa-show-key): New command.

[Jonas Bernoulli <jonas@bernoul.li>]

Users can move in `epa-key-list-mode' buffers using either
`next-line'/`previous-line' or `widget-forward'/`widget-backward'.
When using the first set of commands, then the cursor stays in the
current column and that normally is the first column.  The key
widgets do not begin until the third character of their respective
lines.

All `epa' commands work regardless of whether the cursor is on the
widget or before them.  The `epa-show-key' command did not exist until
now because the `widget-button-press' already performs its task.  But
because the widgets don't span complete lines we actually need this
command too.
---
 lisp/epa.el | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lisp/epa.el b/lisp/epa.el
index 8f45c667b9..3c7dd8309a 100644
--- a/lisp/epa.el
+++ b/lisp/epa.el
@@ -25,7 +25,9 @@
 (require 'epg)
 (require 'font-lock)
 (require 'widget)
-(eval-when-compile (require 'wid-edit))
+(eval-when-compile
+  (require 'subr-x)
+  (require 'wid-edit))
 (require 'derived)
 
 (defgroup epa nil
@@ -189,6 +191,7 @@ epa-key-list-mode-map
   (let ((keymap (make-sparse-keymap))
 	(menu-map (make-sparse-keymap)))
     (set-keymap-parent keymap widget-keymap)
+    (define-key keymap "\C-m" 'epa-show-key)
     (define-key keymap "m" 'epa-mark-key)
     (define-key keymap "u" 'epa-unmark-key)
     (define-key keymap "d" 'epa-decrypt-file)
@@ -502,6 +505,14 @@ epa-select-keys
   (let ((keys (epg-list-keys context names secret)))
     (epa--select-keys prompt keys)))
 
+(defun epa-show-key ()
+  "Show a key on the current line."
+  (interactive)
+  (if-let ((key (get-text-property (point) 'epa-key)))
+      (save-selected-window
+        (epa--show-key key))
+    (error "No key on this line")))
+
 (defun epa--show-key (key)
   (let* ((primary-sub-key (car (epg-key-sub-key-list key)))
 	 (entry (assoc (epg-sub-key-id primary-sub-key)
-- 
2.26.0