Introduced interface for FactoryRegistryPlugin

Created by: stefanoborini

To simplify testing, we needed to introduce probe classes. The initial approach was to override the FactoryRegistryPlugin and replace the extension points with simple lists, but this turned out not to work. We therefore introduced an interface, and changed all traits to handle the interface instead of the class.

force_bdss/io/workflow_reader.py

@@ -5,7 +5,7 @@ from traits.api import HasStrictTraits, Instance
 
 from force_bdss.core.input_slot_map import InputSlotMap
 from force_bdss.core.workflow import Workflow
-from ..factory_registry_plugin import FactoryRegistryPlugin
+from ..factory_registry_plugin import IFactoryRegistryPlugin
 
 SUPPORTED_FILE_VERSIONS = ["1"]
 
@@ -25,7 +25,7 @@ class WorkflowReader(HasStrictTraits):
     """
     #: The Factory registry. The reader needs it to create the
     #: specific model objects.
-    factory_registry = Instance(FactoryRegistryPlugin)
+    factory_registry = Instance(IFactoryRegistryPlugin)
 
     def __init__(self,
                  factory_registry,