test_common: create_inbox: use `$!' properly on mkdir failure

stat(2) may fail and set `$!', too, so we must stash it, first.

1 files changed, 3 insertions, 3 deletions

diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index 5807105a..ed28ac48 100644
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -709,9 +709,9 @@ sub create_inbox ($$;@) {
         my ($db) = (PublicInbox::Import::default_branch() =~ m!([^/]+)\z!);
         my $dir = "t/data-gen/$base.$ident-$db";
         my $new = !-d $dir;
-        if ($new) {
-                mkdir $dir; # may race
-                -d $dir or BAIL_OUT "$dir could not be created: $!";
+        if ($new && !mkdir($dir)) {
+                my $err = $!;
+                -d $dir or xbail "mkdir($dir): $err";
         }
         my $lk = bless { lock_path => "$dir/creat.lock" }, 'PublicInbox::Lock';
         $opt{inboxdir} = File::Spec->rel2abs($dir);