Include module with type name in validation errors (python) (#178)

* Include module with type name in validation errors

* Fix linter error

* fix test under py2

* Update stone_validators.py

Co-authored-by: Connor Worley <cworley@dropbox.com>

stone/backends/python_rsrc/stone_validators.py

@@ -69,7 +69,13 @@ def __repr__(self):
         return 'ValidationError(%r)' % six.text_type(self)
 
 
+def type_name_with_module(t):
+    # type: (typing.Type[typing.Any]) -> six.text_type
+    return '%s.%s' % (t.__module__, t.__name__)
+
+
 def generic_type_name(v):
+    # type: (typing.Any) -> six.text_type
     """Return a descriptive type name that isn't Python specific. For example,
     an int value will return 'integer' rather than 'int'."""
     if isinstance(v, bool):
@@ -87,7 +93,7 @@ def generic_type_name(v):
     elif v is None:
         return 'null'
     else:
-        return type(v).__name__
+        return type_name_with_module(type(v))
 
 
 class Validator(six.with_metaclass(ABCMeta, object)):
@@ -535,7 +541,11 @@ def validate_type_only(self, val):
         # relies on the parent class.
         if not isinstance(val, self.definition):
             raise ValidationError('expected type %s, got %s' %
-                (self.definition.__name__, generic_type_name(val)))
+                (
+                    type_name_with_module(self.definition),
+                    generic_type_name(val),
+                ),
+            )
 
     def has_default(self):
         return not self.definition._has_required_fields
@@ -600,7 +610,11 @@ def validate_type_only(self, val):
         """
         if not issubclass(self.definition, type(val)):
             raise ValidationError('expected type %s or subtype, got %s' %
-                (self.definition.__name__, generic_type_name(val)))
+                (
+                    type_name_with_module(self.definition),
+                    generic_type_name(val),
+                ),
+            )
 
 
 class Void(Primitive):

test/test_python_gen.py

@@ -652,6 +652,14 @@ def _get_val_data_type(cls, tag, cp):
                 self.assertEqual(prefix, str(e)[:len(prefix)])
                 raise
 
+    def test_type_name_with_module(self):
+        class Foo():
+            def __init__(self):
+                pass
+
+        assert bv.type_name_with_module(Foo) == "test.test_python_gen.Foo"
+        assert bv.type_name_with_module(int) == "builtins.int" if six.PY3 else "__builtin__.int"
+
 
 test_spec = """\
 namespace ns