Added automagic argument checking when running functions.

system/workflow.py

@@ -1,7 +1,7 @@
-
 import gtk
 import sys
 import os
+import inspect
 from system import logger
 
 def _workflow_classes(modname):
@@ -174,17 +174,27 @@ class WorkflowView (gtk.VBox):
         if not validation.succeeded:
             logger.log('warning','Invalid Inputdata: ' + str(reason))
             return
-        
-        argcount =function.run.func_code.co_argcount - 1
-        
-        if  argcount != len(parent_data) and argcount != 0:
-            logger.log('warning','Method requires ' + str(argcount) + ' Data. ' + str(len(parent_data)) + ' selected')
+
+        args, varargs, varkw, defaults = inspect.getargspec(function.run)
+
+        # first argument is 'self' and we don't care about that...
+        args = args[1:]
+
+        if varargs and len(parent_data) < len(args):
+            logger.log('warning', "Function requires minimum %d datasets selected." % len(args))
+            return
+        elif not varargs and args and len(args) != len(parent_data):
+            # functions requiring datasets have to have the right number
+            logger.log('warning', "Function requires %d datasets, but only %d selected." % (len(args), len(parent_data)))
             return
 
-        if not project.current_data or argcount == 0:
+        # we allow functions requiring no data to be run even if
+        # something is selected
+
+        if not args:
             new_data = function.run()
         else:
-            new_data = function.run(*project.current_data)
+            new_data = function.run(*parent_data)
 
         if new_data != None:
             project.add_data(parent_data, new_data, function.name)