master 7bfb35f8a7: Make M-S-x output better in mode that have bindings for `undefined'

[Lars Ingebrigtsen]

branch: master
commit 7bfb35f8a7b364877c5a07297f16bc38d00f1989
Author: Lars Ingebrigtsen <larsi@gnus.org>
Commit: Lars Ingebrigtsen <larsi@gnus.org>

    Make M-S-x output better in mode that have bindings for `undefined'
    
    * lisp/simple.el (command-completion-using-modes-p): Speed up case
    when there's no command modes.
    (execute-extended-command-for-buffer): Make M-S-x output better
    (bug#46665).
---
 lisp/simple.el | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/lisp/simple.el b/lisp/simple.el
index 99c951b24b..f2b3d82a7a 100644
--- a/lisp/simple.el
+++ b/lisp/simple.el
@@ -2299,7 +2299,7 @@ This function uses the `read-extended-command-predicate' 
user option."
 (defun command-completion-using-modes-p (symbol buffer)
   "Say whether SYMBOL has been marked as a mode-specific command in BUFFER."
   ;; Check the modes.
-  (let ((modes (command-modes symbol)))
+  (when-let ((modes (command-modes symbol)))
     ;; Common fast case: Just a single mode.
     (if (null (cdr modes))
         (or (provided-mode-derived-p
@@ -2539,7 +2539,16 @@ maps."
           (read-extended-command-predicate
            (lambda (symbol buffer)
              (or (command-completion-using-modes-p symbol buffer)
-                 (where-is-internal symbol keymaps)))))
+                 ;; Include commands that are bound in a keymap in the
+                 ;; current buffer.
+                 (and (where-is-internal symbol keymaps)
+                      ;; But not if they have a command predicate that
+                      ;; says that they shouldn't.  (This is the case
+                      ;; for `ignore' and `undefined' and similar
+                      ;; commands commonly found in keymaps.)
+                      (or (null (get symbol 'completion-predicate))
+                          (funcall (get symbol 'completion-predicate)
+                                   symbol buffer)))))))
      (list current-prefix-arg
            (read-extended-command)
            execute-extended-command--last-typed)))