1 files changed, 6 insertions, 0 deletions

diff --git a/src/editfns.c b/src/editfns.c
index bf4976273aa..57c96ff7844 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -531,6 +531,12 @@ find_field (pos, merge_at_boundary, beg_limit, beg, end_limit, end)
         at_field_end = 1;
       if (!EQ (field, before_field))
         at_field_start = 1;
+      if (NILP (field) && at_field_start && at_field_end)
+        /* If an inserted char would have a nil field while the surrounding
+           text is non-nil, we're probably not looking at a
+           zero-length field, but instead at a non-nil field that's
+           not intended for editing (such as comint's prompts).  */
+        at_field_end = at_field_start = 0;
     }
 
   /* Note about special `boundary' fields: