t/www_listing.t | 6 ++++--

diff --git a/t/www_listing.t b/t/www_listing.t
index 39c1957756bb367c7618541abcb3d557fc168383..9230329ccd79650c4165d6623351c99142efd638 100644
--- a/t/www_listing.t
+++ b/t/www_listing.t
@@ -9,8 +9,10 @@ use PublicInbox::TestCommon;
 require_mods(qw(URI::Escape Plack::Builder Digest::SHA
 		IO::Compress::Gzip IO::Uncompress::Gunzip HTTP::Tiny));
 require PublicInbox::WwwListing;
-my $json = $PublicInbox::WwwListing::json or
-	plan skip_all => "JSON module missing";
+my $json = do {
+	no warnings 'once';
+	$PublicInbox::WwwListing::json;
+} or plan skip_all => "JSON module missing";
 
 use_ok 'PublicInbox::Git';