send-email: fix uninitialized var warning for $smtp_auth

On the latest version of git-send-email, I see this error just before running SMTP auth (I didn't provide any --smtp-auth= parameter): Use of uninitialized value $smtp_auth in pattern match (m//) at \ /home/briannorris/git/git/git-send-email.perl line 1139. Signed-off-by: Brian Norris <computersforpeace@gmail.com> Reviewed-by: Eric Sunshine <sunshine@sunshineco.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Brian Norris committed Sep 18, 2015 at 15:12 UTC 904f6e7c15ab50c02048f50002d8f72b9ed74075
1 file changed +1 -1
git-send-email.perl
+1 -1
@@ -1142,7 +1142,7 @@ sub smtp_auth_maybe {
1142
1143 # Check mechanism naming as defined in:
1144 # https://tools.ietf.org/html/rfc4422#page-8
1145 - if ($smtp_auth !~ /^(\b[A-Z0-9-_]{1,20}\s*)*$/) {
1145 + if ($smtp_auth && $smtp_auth !~ /^(\b[A-Z0-9-_]{1,20}\s*)*$/) {
1146 die "invalid smtp auth: '${smtp_auth}'";
1147 }
1148