Bug 1446236 - Add simpler method to check if an extension is present

Bugzilla.pm

@@ -123,9 +123,19 @@ sub template_inner {
     ||= Bugzilla::Template->create(%options);
 }
 
+our $in_extensions = 0;
+
 sub extensions {
   state $extensions;
   return $extensions if $extensions;
+
+  # Guard against extensions querying the extension list during initialization
+  # (through this method or has_extension).
+  # The extension list is not fully populated at that point,
+  # so the results would not be meaningful.
+  die "Recursive attempt to load/query extensions" if $in_extensions > 0;
+  local $in_extensions = $in_extensions + 1;
+
   my $extension_packages = Bugzilla::Extension->load_all();
   $extensions = [];
   foreach my $package (@$extension_packages) {
@@ -136,6 +146,16 @@ sub extensions {
   return $extensions;
 }
 
+sub has_extension {
+  my ($class, $name) = @_;
+  my $cache = $class->request_cache;
+  if (!$cache->{extensions_hash}) {
+    my %extensions = map { $_->NAME => 1 } @{Bugzilla->extensions};
+    $cache->{extensions_hash} = \%extensions;
+  }
+  return exists $cache->{extensions_hash}{$name};
+}
+
 sub cgi {
   return request_cache->{cgi} ||= Bugzilla::CGI->new;
 }

votes.cgi

@@ -30,8 +30,7 @@ use lib qw(. lib local/lib/perl5);
 use Bugzilla;
 use Bugzilla::Error;
 
-my $is_enabled = grep { $_->NAME eq 'Voting' } @{Bugzilla->extensions};
-$is_enabled || ThrowCodeError('extension_disabled', {name => 'Voting'});
+Bugzilla->has_extension('Voting') || ThrowCodeError('extension_disabled', { name => 'Voting' });
 
 my $cgi = Bugzilla->cgi;
 my $action = $cgi->param('action') || 'show_user';