New API for parameters

force_bdss/mco/parameters/base_mco_parameter_factory.py

@@ -13,20 +13,22 @@ class BaseMCOParameterFactory(HasStrictTraits):
     """
 
     #: A reference to the MCO factory this parameter factory lives in.
-    mco_factory = Instance('force_bdss.mco.base_mco_factory.BaseMCOFactory')
+    mco_factory = Instance('force_bdss.mco.base_mco_factory.BaseMCOFactory',
+                           allow_none=False)
 
     #: A unique string identifying the parameter
     id = Str()
 
     #: A user friendly name (for the UI)
-    name = Str("Undefined parameter")
+    name = Str()
 
     #: A long description of the parameter
-    description = Str("Undefined parameter")
+    description = Str()
 
     # The model class to instantiate when create_model is called.
     model_class = Type(
-        "force_bdss.mco.parameters.base_mco_parameter.BaseMCOParameter"
+        "force_bdss.mco.parameters.base_mco_parameter.BaseMCOParameter",
+        allow_none=False
     )
 
     def get_identifier(self):
@@ -57,7 +59,17 @@ class BaseMCOParameterFactory(HasStrictTraits):
         self.description = self.get_description()
         self.model_class = self.get_model_class()
         identifier = self.get_identifier()
-        self.id = mco_parameter_id(self.mco_factory.id, identifier)
+        try:
+            id = mco_parameter_id(self.mco_factory.id, identifier)
+        except ValueError:
+            raise ValueError(
+                "Invalid identifier {} returned by "
+                "{}.get_identifier()".format(
+                    identifier,
+                    self.__class__.__name__
+                )
+            )
+        self.id = id
 
     def create_model(self, data_values=None):
         """Creates the instance of the model class and returns it.

force_bdss/mco/parameters/tests/test_base_mco_parameter_factory.py

 import unittest
 
 from envisage.plugin import Plugin
+from traits.trait_errors import TraitError
 
 from force_bdss.mco.base_mco_factory import BaseMCOFactory
 
@@ -21,20 +22,40 @@ class DummyMCOParameter(BaseMCOParameter):
 
 
 class DummyMCOParameterFactory(BaseMCOParameterFactory):
-    id = "foo"
-    name = "bar"
-    description = "baz"
-    model_class = DummyMCOParameter
+    def get_identifier(self):
+        return "foo"
 
+    def get_name(self):
+        return "bar"
 
-class DummyMCOFactory(BaseMCOFactory):
-    pass
+    def get_description(self):
+        return "description"
+
+    def get_model_class(self):
+        return DummyMCOParameter
 
 
 class TestBaseMCOParameterFactory(unittest.TestCase):
+    def setUp(self):
+        self.mco_factory = mock.Mock(
+            spec=BaseMCOFactory,
+            plugin=mock.Mock(
+                spec=Plugin,
+                id="pid"
+            ),
+            id="mcoid"
+        )
+
     def test_initialization(self):
-        factory = DummyMCOParameterFactory(
-            mco_factory=BaseMCOFactory(plugin=mock.Mock(spec=Plugin)))
+        factory = DummyMCOParameterFactory(mco_factory=self.mco_factory)
+        self.assertEqual(factory.id, "mcoid.parameter.foo")
+        self.assertEqual(factory.name, "bar")
+        self.assertEqual(factory.description, "description")
+        self.assertEqual(factory.model_class, DummyMCOParameter)
+        self.assertIsInstance(factory.create_model(), DummyMCOParameter)
+
+    def test_create_model(self):
+        factory = DummyMCOParameterFactory(mco_factory=self.mco_factory)
         model = factory.create_model({"x": 42})
         self.assertIsInstance(model, DummyMCOParameter)
         self.assertEqual(model.x, 42)
@@ -42,3 +63,35 @@ class TestBaseMCOParameterFactory(unittest.TestCase):
         model = factory.create_model()
         self.assertIsInstance(model, DummyMCOParameter)
         self.assertEqual(model.x, 0)
+
+    def test_broken_get_identifier(self):
+        class Broken(DummyMCOParameterFactory):
+            def get_identifier(self):
+                return None
+
+        with self.assertRaises(ValueError):
+            Broken(self.mco_factory)
+
+    def test_broken_get_name(self):
+        class Broken(DummyMCOParameterFactory):
+            def get_name(self):
+                return None
+
+        with self.assertRaises(TraitError):
+            Broken(self.mco_factory)
+
+    def test_broken_get_model_class(self):
+        class Broken(DummyMCOParameterFactory):
+            def get_model_class(self):
+                return None
+
+        with self.assertRaises(TraitError):
+            Broken(self.mco_factory)
+
+    def test_broken_get_description(self):
+        class Broken(DummyMCOParameterFactory):
+            def get_description(self):
+                return None
+
+        with self.assertRaises(TraitError):
+            Broken(self.mco_factory)