Fixes Invariant in union serialization when the value is a LazyObject

reactivated/serialization/__init__.py

@@ -23,6 +23,7 @@
 from django.db import models
 from django.forms.models import ModelChoiceIteratorValue  # type: ignore
 from django.utils.module_loading import import_string
+from django.utils.functional import LazyObject
 
 from reactivated import fields, stubs, utils
 from reactivated.models import ComputedRelation
@@ -1132,6 +1133,10 @@ def serialize(
     if value is None:
         return None
 
+    # If value is a lazy object, resolve it before continuing.
+    if isinstance(value, LazyObject):
+        value = value.__reduce__()[1][0]
+
     serializer: Serializer
     serializer_path = schema.schema.get("serializer", None)
 

tests/serialization.py

@@ -24,6 +24,7 @@
 from django.db.models import IntegerField, Model, UUIDField
 from django.forms.models import ModelChoiceIteratorValue
 from django.utils.translation import gettext, gettext_lazy
+from django.utils.functional import SimpleLazyObject
 from jsonschema import validate
 
 from reactivated import Pick
@@ -608,6 +609,7 @@ def test_simple_union(snapshot):
     assert serialize(["1", "2", "3"], schema) == ["1", "2", "3"]
     assert serialize((5, "hello"), schema) == [5, "hello"]
     assert serialize(True, schema) is True
+    assert serialize(SimpleLazyObject(lambda: "hello"), schema) == "hello"
     assert schema == snapshot