Detect plugins with a broken getsetup and warn.

IkiWiki/Setup.pm

@@ -172,6 +172,11 @@ sub getsetup () {
 			my @s=eval { $IkiWiki::hooks{getsetup}{$plugin}{call}->() };
 			next unless @s;
 
+			if (scalar(@s) % 2 != 0) {
+				print STDERR "warning: plugin $plugin has a broken getsetup; ignoring\n";
+				next;
+			}
+
 			# set default section value (note use of shared
 			# hashref between array and hash)
 			my %s=@s;

debian/changelog

@@ -2,6 +2,7 @@ ikiwiki (3.20130213) UNRELEASED; urgency=low
 
   * Allow dots in directive parameter names. (tango)
   * Add missing plugin section, and deal with missing sections with a warning.
+  * Detect plugins with a broken getsetup and warn.
 
  -- Joey Hess <joeyh@debian.org>  Fri, 15 Feb 2013 17:23:12 -0400