Optimise the case where catalog returns no line.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@18511 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Type/patches/WorkflowTool.py

@@ -371,6 +371,8 @@ def sumCatalogResultByWorklist(grouped_worklist_dict, catalog_result):
     flexibility point of view: if it must ever be changed into a cursor, this
     code will keep working nicely without needing to rewind the cursor.
   """
+  worklist_result_dict = {}
+  if len(catalog_result) > 0:
     # List all unique criterions in criterion_id_list
     criterion_id_dict = {}
     for worklist in grouped_worklist_dict.itervalues():
@@ -397,7 +399,6 @@ def sumCatalogResultByWorklist(grouped_worklist_dict, catalog_result):
         criterion_value_to_worklist_key_dict[criterion_value_key].append(
           worklist_id)
     # Read catalog result and distribute to matching worklists
-  worklist_result_dict = {}
     for result_line in catalog_result:
       criterion_value_key = tuple([result_line[x] for x in criterion_id_list])
       if criterion_value_key not in criterion_value_to_worklist_key_dict: