From a40be60ec89d0eb75cd1e48793f85433de0d3e45 Mon Sep 17 00:00:00 2001
From: Juri Linkov <juri@linkov.net>
Date: Sun, 6 Dec 2020 23:12:13 +0200
Subject: [PATCH] Backport Handle read-char-from-minibuffer and y-or-n-p from
 pre-command-hook

* lisp/subr.el (read-char-from-minibuffer-insert-char)
(read-char-from-minibuffer-insert-other, y-or-n-p-insert-y)
(y-or-n-p-insert-n, y-or-n-p-insert-other):
Check for 'minibufferp' before executing the body.
(read-char-from-minibuffer, y-or-n-p): Let-bind this-command
before calling read-from-minibuffer.  (Bug#45029)

; Do not merge to master.
---
 lisp/subr.el | 47 ++++++++++++++++++++++++++++-------------------
 1 file changed, 28 insertions(+), 19 deletions(-)

diff --git a/lisp/subr.el b/lisp/subr.el
index d5cf7fb0031..9081de55c74 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -2697,20 +2697,22 @@ floating point support."
   "Insert the character you type in the minibuffer and exit.
 Discard all previous input before inserting and exiting the minibuffer."
   (interactive)
-  (delete-minibuffer-contents)
-  (insert last-command-event)
-  (exit-minibuffer))
+  (when (minibufferp)
+    (delete-minibuffer-contents)
+    (insert last-command-event)
+    (exit-minibuffer)))
 
 (defun read-char-from-minibuffer-insert-other ()
   "Handle inserting of a character other than allowed.
 Display an error on trying to insert a disallowed character.
 Also discard all previous input in the minibuffer."
   (interactive)
-  (delete-minibuffer-contents)
-  (ding)
-  (discard-input)
-  (minibuffer-message "Wrong answer")
-  (sit-for 2))
+  (when (minibufferp)
+    (delete-minibuffer-contents)
+    (ding)
+    (discard-input)
+    (minibuffer-message "Wrong answer")
+    (sit-for 2)))
 
 (defvar empty-history)
 
@@ -2737,6 +2739,8 @@ history."
                                  map)
                                read-char-from-minibuffer-map-hash))
                 read-char-from-minibuffer-map))
+         ;; Protect this-command when called from pre-command-hook (bug#45029)
+         (this-command this-command)
          (result
           (read-from-minibuffer prompt nil map nil
                                 (or history 'empty-history)))
@@ -2791,28 +2795,31 @@ history."
   "Insert the answer \"y\" and exit the minibuffer of `y-or-n-p'.
 Discard all previous input before inserting and exiting the minibuffer."
   (interactive)
-  (delete-minibuffer-contents)
-  (insert "y")
-  (exit-minibuffer))
+  (when (minibufferp)
+    (delete-minibuffer-contents)
+    (insert "y")
+    (exit-minibuffer)))
 
 (defun y-or-n-p-insert-n ()
   "Insert the answer \"n\" and exit the minibuffer of `y-or-n-p'.
 Discard all previous input before inserting and exiting the minibuffer."
   (interactive)
-  (delete-minibuffer-contents)
-  (insert "n")
-  (exit-minibuffer))
+  (when (minibufferp)
+    (delete-minibuffer-contents)
+    (insert "n")
+    (exit-minibuffer)))
 
 (defun y-or-n-p-insert-other ()
   "Handle inserting of other answers in the minibuffer of `y-or-n-p'.
 Display an error on trying to insert a disallowed character.
 Also discard all previous input in the minibuffer."
   (interactive)
-  (delete-minibuffer-contents)
-  (ding)
-  (discard-input)
-  (minibuffer-message "Please answer y or n")
-  (sit-for 2))
+  (when (minibufferp)
+    (delete-minibuffer-contents)
+    (ding)
+    (discard-input)
+    (minibuffer-message "Please answer y or n")
+    (sit-for 2)))
 
 (defvar empty-history)
 
@@ -2865,6 +2872,8 @@ is nil and `use-dialog-box' is non-nil."
       (setq prompt (funcall padded prompt))
       (let* ((empty-history '())
              (enable-recursive-minibuffers t)
+             ;; Protect this-command when called from pre-command-hook (bug#45029)
+             (this-command this-command)
              (str (read-from-minibuffer
                    prompt nil
                    (make-composed-keymap y-or-n-p-map query-replace-map)
-- 
2.39.2