Bug with empty xml files is fixed #43

calculate/templates/format/xml_gconf_format.py

@@ -44,6 +44,9 @@ class XMLGConfFormat(Format):
 
         self._initialize_parser()
         self._join_before = join_before
+        if not document_text.strip():
+            document_text = ("<?xml version='1.0' encoding='UTF-8'?>"
+                             "<gconf></gconf>")
 
         if add_header and not ignore_comments:
             self.header, document_text = self._get_header_and_document_text(

calculate/templates/format/xml_xfce_format.py

@@ -39,6 +39,10 @@ class XMLXfceFormat(Format):
         self._initialize_parser()
         self._join_before = join_before
 
+        if not document_text.strip():
+            document_text = ("<?xml version='1.0' encoding='UTF-8'?>"
+                             "<gconf></gconf>")
+
         if add_header and not ignore_comments:
             self.header, document_text = self._get_header_and_document_text(
                                                document_text,