Added support for async SerializerMethodField

adrf/fields.py

@@ -1,5 +1,6 @@
 from rest_framework.serializers import SerializerMethodField as DRFSerializerMethodField
 
+
 class SerializerMethodField(DRFSerializerMethodField):
     async def ato_representation(self, attribute):
         method = getattr(self.parent, self.method_name)

tests/test_serializers.py

@@ -5,6 +5,7 @@
 from rest_framework import serializers
 from rest_framework.test import APIRequestFactory
 
+from adrf.fields import SerializerMethodField
 from adrf.serializers import ModelSerializer, Serializer
 
 from .models import Order, User
@@ -254,3 +255,39 @@ async def test_order_serializer_valid(self):
         assert await sync_to_async(serializer.is_valid)()
         assert await serializer.adata == data
         assert serializer.errors == {}
+
+
+class TestSerializerWithSerializerMethodField(TestCase):
+    def test_sync_serializer_valid(self):
+        class SimpleSerializer(Serializer):
+            username = serializers.CharField()
+            age = SerializerMethodField()
+
+            def get_age(self, obj):
+                return 1900
+
+        data = {
+            "username": "test",
+        }
+        data_with_age = {"age": 1900, **data}
+        serializer = SimpleSerializer(data=data)
+        assert serializer.is_valid()
+        assert serializer.data == data_with_age
+        assert serializer.errors == {}
+
+    async def test_async_serializer_valid(self):
+        class SimpleAsyncSerializer(Serializer):
+            username = serializers.CharField()
+            age = SerializerMethodField()
+
+            async def get_age(self, obj):
+                return 1900
+
+        data = {
+            "username": "test",
+        }
+        data_with_age = {"age": 1900, **data}
+        serializer = SimpleAsyncSerializer(data=data)
+        assert serializer.is_valid()
+        assert await serializer.adata == data_with_age
+        assert serializer.errors == {}