diff --git a/t/tei.t b/t/tei.t
index 6dca05c..928d28f 100644
--- a/t/tei.t
+++ b/t/tei.t
@@ -9,38 +9,68 @@
 
 use Test::KorAP::XML::TEI qw!korap_tempfile!;
 
-use_ok('KorAP::XML::TEI', 'remove_xml_comments');
+use_ok('KorAP::XML::TEI', 'remove_xml_comments', 'escape_xml');
 
-my ($fh, $filename) = korap_tempfile('tei');
+subtest 'remove_xml_comments' => sub {
+  my ($fh, $filename) = korap_tempfile('tei');
 
-print $fh <<'HTML';
+  print $fh <<'HTML';
 mehrzeiliger
 Kommentar
   -->
 Test
 HTML
 
-is(remove_xml_comments($fh, "hallo"),"hallo");
-is(remove_xml_comments($fh, "hallo <!-- Test -->"),"hallo ");
-is(remove_xml_comments($fh, "<!-- Test --> hallo")," hallo");
+  is(remove_xml_comments($fh, "hallo"),"hallo");
+  is(remove_xml_comments($fh, "hallo <!-- Test -->"),"hallo ");
+  is(remove_xml_comments($fh, "<!-- Test --> hallo")," hallo");
 
-seek($fh, 0, 0);
+  seek($fh, 0, 0);
 
-is(remove_xml_comments($fh, '<!--'), "Test\n");
+  is(remove_xml_comments($fh, '<!--'), "Test\n");
 
-seek($fh, 0, 0);
+  seek($fh, 0, 0);
 
-print $fh <<'HTML';
+  print $fh <<'HTML';
 mehrzeiliger
 Kommentar
   --><!-- Versuch
 -->ist <!-- a --><!-- b --> ein Test
 HTML
 
-seek($fh, 0, 0);
+  seek($fh, 0, 0);
 
-is(remove_xml_comments($fh, 'Dies <!--'), "Dies ist  ein Test\n");
+  is(remove_xml_comments($fh, 'Dies <!--'), "Dies ist  ein Test\n");
 
-close($fh);
+  close($fh);
+};
+
+subtest 'escape_xml' => sub {
+  is(
+    escape_xml('"""'),
+    '&quot;&quot;&quot;'
+  );
+
+  is(
+    escape_xml('&&&'),
+    '&amp;&amp;&amp;'
+  );
+
+  is(
+    escape_xml('<<<'),
+    '&lt;&lt;&lt;'
+  );
+
+  is(
+    escape_xml('>>>'),
+    '&gt;&gt;&gt;'
+  );
+
+  is(
+    escape_xml('<tag att1="foo" att2="bar">C&A</tag>'),
+    '&lt;tag att1=&quot;foo&quot; att2=&quot;bar&quot;&gt;C&amp;A&lt;/tag&gt;'
+  );
+};
+
 
 done_testing;