master 6f0bb2f 02/10: Merge from origin/emacs-27

[Glenn Morris]

branch: master
commit 6f0bb2fe589e6b42666640d290e2e82ac24c8583
Merge: dadffdd 7384ec6
Author: Glenn Morris <rgm@gnu.org>
Commit: Glenn Morris <rgm@gnu.org>

    Merge from origin/emacs-27
    
    7384ec6416 Add warning comments abound binding keys in Isearch maps
---
 lisp/isearch.el | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lisp/isearch.el b/lisp/isearch.el
index fefdd16..67cc7be 100644
--- a/lisp/isearch.el
+++ b/lisp/isearch.el
@@ -669,6 +669,10 @@ This is like `describe-bindings', but displays only 
Isearch keys."
                              (if isearch-success 'isearch-abort binding))))
     map))
 
+;; Note: Before adding more key bindings to this map, please keep in
+;; mind that any unbound key exits Isearch and runs the command bound
+;; to it in the local or global map.  So in effect every key unbound
+;; in this map is implicitly bound.
 (defvar isearch-mode-map
   (let ((i 0)
        (map (make-keymap)))
@@ -834,6 +838,10 @@ This is like `describe-bindings', but displays only 
Isearch keys."
             :image '(isearch-tool-bar-image "left-arrow")))
     map))
 
+;; Note: Before adding more key bindings to this map, please keep in
+;; mind that any unbound key exits Isearch and runs the command bound
+;; to it in the local or global map.  So in effect every key unbound
+;; in this map is implicitly bound.
 (defvar minibuffer-local-isearch-map
   (let ((map (make-sparse-keymap)))
     (set-keymap-parent map minibuffer-local-map)