Integrated changes from master.

graphene/types/schema.py

@@ -311,20 +311,17 @@ class TypeMap(dict):
                         if isinstance(arg.type, NonNull)
                         else arg.default_value,
                     )
-                resolve = field.get_resolver(
-                    self.get_resolver(graphene_type, name, field.default_value)
-                )
                 _field = GraphQLField(
                     field_type,
                     args=args,
                     resolve=field.get_resolver(
                         self.get_resolver_for_type(
-                            type_, "resolve_{}", name, field.default_value
+                            graphene_type, "resolve_{}", name, field.default_value
                         )
                     ),
                     subscribe=field.get_resolver(
                         self.get_resolver_for_type(
-                            type_, "subscribe_{}", name, field.default_value
+                            graphene_type, "subscribe_{}", name, field.default_value
                         )
                     ),
                     deprecation_reason=field.deprecation_reason,
@@ -334,11 +331,11 @@ class TypeMap(dict):
             fields[field_name] = _field
         return fields
 
-    def get_resolver_for_type(self, type_, pattern, name, default_value):
-        if not issubclass(type_, ObjectType):
+    def get_resolver_for_type(self, graphene_type, pattern, name, default_value):
+        if not issubclass(graphene_type, ObjectType):
             return
         func_name = pattern.format(name)
-        resolver = getattr(type_, func_name, None)
+        resolver = getattr(graphene_type, func_name, None)
         if not resolver:
             # If we don't find the resolver in the ObjectType class, then try to
             # find it in each of the interfaces
@@ -360,6 +357,48 @@ class TypeMap(dict):
         )
         return partial(default_resolver, name, default_value)
 
+    def resolve_type(self, resolve_type_func, type_name, root, info, _type):
+        type_ = resolve_type_func(root, info)
+
+        if not type_:
+            return_type = self[type_name]
+            return default_type_resolver(root, info, return_type)
+
+        if inspect.isclass(type_) and issubclass(type_, ObjectType):
+            graphql_type = self.get(type_._meta.name)
+            assert graphql_type, "Can't find type {} in schema".format(type_._meta.name)
+            assert graphql_type.graphene_type == type_, (
+                "The type {} does not match with the associated graphene type {}."
+            ).format(type_, graphql_type.graphene_type)
+            return graphql_type
+
+        return type_
+
+    def get_resolver(self, graphene_type, name, default_value):
+        if not issubclass(graphene_type, ObjectType):
+            return
+        resolver = getattr(graphene_type, "resolve_{}".format(name), None)
+        if not resolver:
+            # If we don't find the resolver in the ObjectType class, then try to
+            # find it in each of the interfaces
+            interface_resolver = None
+            for interface in graphene_type._meta.interfaces:
+                if name not in interface._meta.fields:
+                    continue
+                interface_resolver = getattr(interface, "resolve_{}".format(name), None)
+                if interface_resolver:
+                    break
+            resolver = interface_resolver
+
+        # Only if is not decorated with classmethod
+        if resolver:
+            return get_unbound_function(resolver)
+
+        default_resolver = (
+            graphene_type._meta.default_resolver or get_default_resolver()
+        )
+        return partial(default_resolver, name, default_value)
+
 
 class Schema:
     """Schema Definition.