* (log-edit-show-diff): Error out if the diff function is not set.

1 files changed, 3 insertions, 1 deletions

diff --git a/lisp/log-edit.el b/lisp/log-edit.el
index 46f1544d9eb..a2f749ad127 100644
--- a/lisp/log-edit.el
+++ b/lisp/log-edit.el
@@ -435,7 +435,9 @@ If you want to abort the commit, simply delete the buffer."
 (defun log-edit-show-diff ()
   "Show the diff for the files to be committed."
   (interactive)
-  (funcall log-edit-diff-function))
+  (if (functionp log-edit-diff-function)
+      (funcall log-edit-diff-function)
+    (error "Diff functionality has not been setup")))
 
 (defun log-edit-show-files ()
   "Show the list of files to be committed."