Fix warning

Signed-off-by: Simo Sorce <simo@redhat.com>

diff --git a/tests/helpers/http.py b/tests/helpers/http.py
index 425d6b7..833637f 100755 (executable)
--- a/tests/helpers/http.py
+++ b/tests/helpers/http.py
@@ -37,7 +37,7 @@ class PageTree(object):
 
     @property
     def tree(self):
 
     @property
     def tree(self):

-        if not self._tree:
+        if self._tree is None:

             self._tree = html.fromstring(self.text)
         return self._tree
 
             self._tree = html.fromstring(self.text)
         return self._tree