Take kwargs in marshmallow post-processors

This is expected by upstream, and they have added arguments in newer
releases.

Fixes: #859

Author: stefanor

tests/test_context_factory.py

@@ -128,7 +128,7 @@ class UserSchema(Schema):
             name = fields.Str()
 
             @post_dump()
-            def check_context(self, data):
+            def check_context(self, data, **kwargs):
                 assert self.context["test"] == "context"
                 self.context["test_number"] += 1
 
@@ -304,7 +304,7 @@ class UserSchema(Schema):
             name = fields.Str()
 
             @post_dump()
-            def check_context(self, data):
+            def check_context(self, data, **kwargs):
                 assert self.context["test"] == "context"
                 self.context["test_number"] += 1
 
@@ -479,7 +479,7 @@ class UserSchema(Schema):
             name = fields.Str()
 
             @post_dump()
-            def check_context(self, data):
+            def check_context(self, data, **kwargs):
                 assert self.context["test"] == "context"
                 self.context["test_number"] += 1
 

tests/test_types.py

@@ -464,7 +464,7 @@ class MarshmallowContextSchema(Schema):
         name = fields.String()
 
         @validates_schema
-        def check_context(self, data):
+        def check_context(self, data, **kwargs):
             assert self.context == custom_context
             self.context["marshmallow"] += 1