1 files changed, 25 insertions, 2 deletions
diff --git a/src/nvim/regexp.c b/src/nvim/regexp.c
index d6f207a248..68ffc70457 100644
--- a/src/nvim/regexp.c
+++ b/src/nvim/regexp.c
@@ -481,13 +481,33 @@ static char_u *skip_anyof(char *p)
 }
 
 /// Skip past regular expression.
-/// Stop at end of "startp" or where "dirc" is found ('/', '?', etc).
+/// Stop at end of "startp" or where "delim" is found ('/', '?', etc).
 /// Take care of characters with a backslash in front of it.
 /// Skip strings inside [ and ].
+char *skip_regexp(char *startp, int delim, int magic)
+{
+  return skip_regexp_ex(startp, delim, magic, NULL, NULL);
+}
+
+/// Call skip_regexp() and when the delimiter does not match give an error and
+/// return NULL.
+char *skip_regexp_err(char *startp, int delim, int magic)
+{
+  char *p = skip_regexp(startp, delim, magic);
+
+  if (*p != delim) {
+    semsg(_("E654: missing delimiter after search pattern: %s"), startp);
+    return NULL;
+  }
+  return p;
+}
+
+/// skip_regexp() with extra arguments:
 /// When "newp" is not NULL and "dirc" is '?', make an allocated copy of the
 /// expression and change "\?" to "?".  If "*newp" is not NULL the expression
 /// is changed in-place.
-char *skip_regexp(char *startp, int dirc, int magic, char **newp)
+/// If a "\?" is changed to "?" then "dropped" is incremented, unless NULL.
+char *skip_regexp_ex(char *startp, int dirc, int magic, char **newp, int *dropped)
 {
   int mymagic;
   char *p = startp;
@@ -516,6 +536,9 @@ char *skip_regexp(char *startp, int dirc, int magic, char **newp)
           *newp = xstrdup(startp);
           p = *newp + (p - startp);
         }
+        if (dropped != NULL) {
+          (*dropped)++;
+        }
         STRMOVE(p, p + 1);
       } else {
         p++;            // skip next character