WWIP: Variable/Guard.

product/ERP5Workflow/Document/WorkflowVariable.py

@@ -67,7 +67,7 @@ class WorkflowVariable(IdAsReferenceMixin("variable_", "prefix"), XMLObject,
     )
 
     def _setVariableExpression(self, expression):
-      if isinstance(expression, str) and expression != '':
+      if isinstance(expression, basestring) and expression:
         self.setVariableExpressionText(expression)
       elif isinstance(expression, Expression) and expression.text:
         self.variable_expression = expression

product/ERP5Workflow/mixin/guardable.py

@@ -96,6 +96,7 @@ class GuardableMixin(object):
         return False
     return True
 
+  # Same as WorkflowVariable.variable_expression
   def _setGuardExpression(self, text):
     if text:
       self.guard_expression = Expression(text)