vis: fix one more coverity scan warning

With the current code this will never cause a NULL dereference
since it is checked at the call site. However it makes sense
to check it anyway.

1 files changed, 2 insertions, 2 deletions

diff --git a/vis.c b/vis.c
index 5181d92..f630e7f 100644
--- a/vis.c
+++ b/vis.c
@@ -1683,8 +1683,8 @@ static bool cmd_set(Filerange *range, enum CmdOpt cmdopt, const char *argv[]) {
 }
 
 static bool is_file_pattern(const char *pattern) {
-	return strcmp(pattern, ".") == 0 || strchr(pattern, '*') ||
-	       strchr(pattern, '[') || strchr(pattern, '{');
+	return pattern && (strcmp(pattern, ".") == 0 || strchr(pattern, '*') ||
+	       strchr(pattern, '[') || strchr(pattern, '{'));
 }
 
 static const char *file_open_dialog(const char *pattern) {