show a no documentation warning, fixes #164

test/documentation.vim

@@ -1,10 +1,15 @@
 source plugin/jedi.vim
 
-describe 'documentation_docstrings'
+describe 'documentation docstrings'
     before
         set filetype=python
     end
 
+    after
+        bd!
+        bd!
+    end
+
     it 'simple'
         put = 'ImportError'
         normal GK
@@ -15,6 +20,12 @@ describe 'documentation_docstrings'
         normal K
         Expect bufname('%') == ''
     end
+
+    it 'no documentation'
+        put = 'x = 2'
+        normal G0K
+        Expect bufname('%') == ''
+    end
 end
 
 " vim: et:ts=4:sw=4