Add a simple unit test for [[!toc]]

t/toc.t

@@ -0,0 +1,42 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+use Test::More;
+use Encode;
+
+BEGIN { use_ok("IkiWiki"); }
+BEGIN { use_ok("IkiWiki::Render"); }
+
+%config=IkiWiki::defaultconfig();
+$config{srcdir}=$config{destdir}="/dev/null";
+$config{add_plugins}=[qw(toc)];
+IkiWiki::loadplugins();
+IkiWiki::checkconfig();
+
+sub render {
+	my $content = shift;
+	$IkiWiki::pagesources{foo} = "foo.mdwn";
+	$IkiWiki::pagemtime{foo} = 42;
+	$IkiWiki::pagectime{foo} = 42;
+	$content = IkiWiki::filter("foo", "foo", $content);
+	$content = IkiWiki::preprocess("foo", "foo", $content);
+	$content = IkiWiki::linkify("foo", "foo", $content);
+	$content = IkiWiki::htmlize("foo", "foo", "mdwn", $content);
+	$content = IkiWiki::genpage("foo", $content);
+	return $content;
+}
+
+# https://ikiwiki.info/todo/toc-with-human-readable-anchors/
+# (toc-recycle-id part)
+like(render('[[!toc ]]
+## Weasels
+
+These mustelids are weasilly recognised
+
+<h2 id="the-chapter-on-stoats">Stoats</h2>
+
+These are stoatally different
+'),
+	qr{(?s)<a href="\#index1h2">.*<a href="\#the-chapter-on-stoats">});
+
+done_testing();