removed unused code is_valid_for and value_for

IPython/utils/tests/test_traitlets.py

@@ -89,28 +89,6 b' class TestTraitType(TestCase):'
             tt = MyIntTT('bad default')
         self.assertRaises(TraitError, B)
 
-    def test_is_valid_for(self):
-        class MyTT(TraitType):
-            def is_valid_for(self, value):
-                return True
-        class A(HasTraits):
-            tt = MyTT
-
-        a = A()
-        a.tt = 10
-        self.assertEqual(a.tt, 10)
-
-    def test_value_for(self):
-        class MyTT(TraitType):
-            def value_for(self, value):
-                return 20
-        class A(HasTraits):
-            tt = MyTT
-
-        a = A()
-        a.tt = 10
-        self.assertEqual(a.tt, 20)
-
     def test_info(self):
         class A(HasTraits):
             tt = TraitType

IPython/utils/traitlets.py

@@ -447,20 +447,11 b' class TraitType(object):'
     def _validate(self, obj, value):
         if value is None and self.allow_none:
             return value
+        if hasattr(self, 'validate'):
+            value = self.validate(obj, value)
         if 'validate' in self._metadata:
             value = self._metadata['validate'](obj, value, self)
-        if hasattr(self, 'validate'):
-            return self.validate(obj, value)
-        elif hasattr(self, 'is_valid_for'):
-            valid = self.is_valid_for(value)
-            if valid:
-                return value
-            else:
-                raise TraitError('invalid value for type: %r' % value)
-        elif hasattr(self, 'value_for'):
-            return self.value_for(value)
-        else:
-            return value
+        return value
 
     def __or__(self, other):
         if isinstance(other, Union):