Make electric-pair-mode, delete-selection-mode and CC Mode cooperate.

Fixes debbugs#21275.

In Emacs >= 25, let electric-pair-mode take precedence over
delete-selection-mode.
delsel.el (delete-selection-uses-region-p): New function, previously a
lambda expression in a property value for `self-insert-command'.
(top-level) Set the `delete-selection' property of `self-insert-command'
to `delete-selection-uses-region-p'.

progmodes/cc-cmds.el (top-level): Give the `delete-selection' property
for c-electric-\(brace\|paren\) the value `delete-selection-uses-region-p'
when the latter function exists.

1 files changed, 11 insertions, 4 deletions

diff --git a/lisp/delsel.el b/lisp/delsel.el
index 740b60345ed..586c130020b 100644
--- a/lisp/delsel.el
+++ b/lisp/delsel.el
@@ -231,10 +231,17 @@ See `delete-selection-helper'."
     (delete-selection-helper (and (symbolp this-command)
                                   (get this-command 'delete-selection)))))
 
-(put 'self-insert-command 'delete-selection
-     (lambda ()
-       (not (run-hook-with-args-until-success
-             'self-insert-uses-region-functions))))
+(defun delete-selection-uses-region-p ()
+  "Return t when the current command will be using the region
+rather than having `delete-selection' delete it, nil otherwise.
+
+This function is intended for use as the value of the
+`delete-selection' property of a command, and shouldn't be used
+for anything else."
+  (not (run-hook-with-args-until-success
+        'self-insert-uses-region-functions)))
+
+(put 'self-insert-command 'delete-selection 'delete-selection-uses-region-p)
 
 (put 'insert-char 'delete-selection t)
 (put 'quoted-insert 'delete-selection t)