Add api_object_schema.utils.loose_isinstance

api_object_schema/binding.py

@@ -1,5 +1,9 @@
 import itertools
 
+from ._compat import PY2, string_types
+from .utils import loose_isinstance
+
+
 class ObjectAPIBinding(object):
 
     """This class is responsible for describing how an API object field translates into a Pythonic
@@ -60,14 +64,31 @@ def get_value_from_api_value(self, system, objtype, obj, api_value):
         returned = api_value
         for translator in itertools.chain(self.from_api_translators, [self._normalize_value]):
             returned = translator(returned)
-        assert isinstance(returned, self._field.type.type)
+        assert returned is None or loose_isinstance(returned, self._field.type.type)
         return returned
 
     def _normalize_value(self, value):
-        return self._field.type.type(value)
+        return self._coerce(value, self._field.type.type)
 
     def _normalize_api_value(self, value):
-        return self._field.type.api_type(value)
+        return self._coerce(value, self._field.type.api_type)
+
+    def _coerce(self, value, result_type):
+        if value is None:
+            return None
+
+        if PY2 and result_type is str:
+            result_type = string_types
+
+        if PY2 and result_type is int:
+            result_type = (int, long)
+
+        if not isinstance(value, result_type):
+            if isinstance(result_type, tuple):
+                value = result_type[0](value)
+            else:
+                value = result_type(value)
+        return value
 
     def get_api_value_from_object(self, system, objtype, obj):
         """Retrieves the API representation of the field from a whole Pythonic object containing it.
@@ -85,10 +106,11 @@ def get_api_value_from_value(self, system, objtype, obj, value):
         :param obj: the object itself. May be ``None``.
         :param value: the Pythonic value for the field
         """
+        returned = value
         for translator in itertools.chain(self.to_api_translators, [self._normalize_api_value]):
-            value = translator(value)
-        assert isinstance(value, self._field.type.api_type)
-        return value
+            returned = translator(returned)
+        assert returned is None or loose_isinstance(returned, self._field.type.api_type)
+        return returned
 
     def set_object_value(self, system, objtype, obj, value):
         """Controls how a Pythonic value is set for a Pythonic object
@@ -124,10 +146,10 @@ def set_api_object_api_value(self, system, objtype, obj, api_obj, api_value):
 class NoBinding(ObjectAPIBinding):
 
     def get_api_value_from_value(self, *args):
-        raise NotImplementedError() # pragma: no cover
+        raise NotImplementedError()  # pragma: no cover
 
     def get_value_from_api_value(self, *args):
-        raise NotImplementedError() # pragma: no cover
+        raise NotImplementedError()  # pragma: no cover
 
 
 class AttributeBinding(ObjectAPIBinding):
@@ -164,6 +186,7 @@ def set_object_value(self, obj, value):
 class FunctionBinding(ObjectAPIBinding):
 
     def __init__(self, get_func=None, set_func=None):
+        super(FunctionBinding, self).__init__()
         self._get_func = get_func
         self._set_func = set_func
 
@@ -187,6 +210,7 @@ def get_object_value(self, system, objtype, obj):
 class ConstBinding(ObjectAPIBinding):
 
     def __init__(self, value):
+        super(ConstBinding, self).__init__()
         self._value = value
 
     def get_object_value(self, system, objtype, obj):
@@ -196,6 +220,7 @@ def get_object_value(self, system, objtype, obj):
 class CountBinding(ObjectAPIBinding):
 
     def __init__(self, list_to_sum_name_or_func):
+        super(CountBinding, self).__init__()
         self._list_name_or_func = list_to_sum_name_or_func
 
     def get_object_value(self, system, objtype, obj):

api_object_schema/field.py

@@ -1,4 +1,3 @@
-from ._compat import string_types, PY2
 from .binding import NoBinding
 from .type_info import TypeInfo
 from sentinels import NOTHING
@@ -66,16 +65,3 @@ def get_is_visible(self, obj):
             return self._is_visible(obj)
         return self._is_visible
 
-    def get_internal_value(self, data):
-        validation_type = self.type.api_type
-        if PY2 and validation_type is str:
-            validation_type = string_types
-
-        if PY2 and validation_type is int:
-            validation_type = (int, long)
-
-        if (validation_type is not bool and isinstance(data, bool)) or (data is not None and not isinstance(data, validation_type)):
-            raise TypeError("{0!r} is not of field internal type(s) {1!r}".format(data, validation_type))
-
-        internal_value = self.type.translator.from_api(data)
-        return internal_value

api_object_schema/utils.py

@@ -0,0 +1,13 @@
+def loose_isinstance(obj, type_):
+    """
+    Like isinstance, only handles ridiculous cases like isinstance(True, int) and isinstance(u"hello", str)
+    """
+    if type_ is int or type_ is long:
+        if isinstance(obj, bool):
+            return False
+        elif isinstance(obj, (int, long)):
+            return True
+        # fallthrough
+    elif type_ is str and isinstance(obj, unicode):
+        return True
+    return isinstance(obj, type_)

tests/test_utils.py

@@ -0,0 +1,13 @@
+from api_object_schema.utils import loose_isinstance
+
+def test_loose_isinstance():
+    for type, matching, not_matching in [
+            (str, ["hello", u"hello"], [1, True, None]),
+            (bool, [True, False], ["s", 1.0, 1]),
+            (int, [100L, 100, 183874837847398473], [1.2, "hello", True, False]),
+            (long, [100L, 100, 183874837847398473], [1.2, "hello", True, False]),
+            ]:
+        for m in matching:
+            assert loose_isinstance(m, type)
+        for m in not_matching:
+            assert not loose_isinstance(m, type)