Merge branch 'master' into issue_562

CHANGES.rst

@@ -37,6 +37,10 @@ Fixes
 
 - prevent ``mkwsgiinstance`` from blowing up parsing ``buildout.cfg``
 
+- Fix ``ZPublisher.HTTPResponse.HTTPBaseResponse.isHTML`` for binary data on
+  Python 3.
+  (`#577 <https://github.com/zopefoundation/Zope/pull/577>`_)
+
 Features
 ++++++++
 

src/ZPublisher/HTTPResponse.py

@@ -461,7 +461,7 @@ def isHTML(self, text):
             try:
                 text = text.decode(self.charset)
             except UnicodeDecodeError:
-                pass
+                return False
         text = text.lstrip()
         # Note that the string can be big, so text.lower().startswith()
         # is more expensive than s[:n].lower().

src/ZPublisher/tests/testHTTPResponse.py

@@ -1354,3 +1354,7 @@ def test_exception_500_text(self):
             self.assertTrue(expected in bytes(body))
             self.assertEqual(response.status, 500)
             self.assertEqual(response.errmsg, 'Internal Server Error')
+
+    def test_isHTML_not_decodable_bytes(self):
+        response = self._makeOne()
+        self.assertFalse(response.isHTML(u'bïñårÿ'.encode('latin1')))