return None on keywords for BaseDefinition.full_name, fixes #94

jedi/api_classes.py

@@ -139,6 +139,9 @@ class BaseDefinition(object):
         """The path to a certain class/function, see #61."""
         path = [unicode(p) for p in self.path]
         # TODO add further checks, the mapping should only occur on stdlib.
+        if not path:
+            return None  # for keywords the path is empty
+
         try:
             path[0] = self._mapping[path[0]]
         except KeyError:

test/regression.py

@@ -324,7 +324,7 @@ class TestFeature(Base):
                                     == 'os.path.join'
         # issue #94
         defs = self.get_def("""import json; json.load(""")
-        defs[0].full_name
+        assert defs[0].full_name is None
 
     def test_full_name_builtin(self):
         self.assertEqual(self.complete('type')[0].full_name, 'type')