From b537c687677d558e7944b08f54e12d146001e99b Mon Sep 17 00:00:00 2001
From: LeSingh1 <sshaurya914@gmail.com>
Date: Sat, 20 Jun 2026 12:25:47 -0700
Subject: [PATCH 1/3] Fix TypeError in RelatedField.get_choices() when
 to_representation returns unhashable type

When a subclass overrides to_representation() to return an unhashable
type such as a dict, RelatedField.get_choices() raises:

  TypeError: unhashable type: 'dict'

because the return value is used directly as a dictionary key.

Fix by converting the representation to str() before using it as the
key. This is safe since HTML select option values are always strings.

Fixes #5141
---
 rest_framework/relations.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rest_framework/relations.py b/rest_framework/relations.py
index 4409bce77c..0f3c0cd037 100644
--- a/rest_framework/relations.py
+++ b/rest_framework/relations.py
@@ -199,7 +199,7 @@ def get_choices(self, cutoff=None):
             queryset = queryset[:cutoff]
 
         return {
-            self.to_representation(item): self.display_value(item) for item in queryset
+            str(self.to_representation(item)): self.display_value(item) for item in queryset
         }
 
     @property

From 072cfa2e3754b42019061561249957185ffed810 Mon Sep 17 00:00:00 2001
From: LeSingh1 <sshaurya914@gmail.com>
Date: Thu, 9 Jul 2026 10:08:08 -0700
Subject: [PATCH 2/3] fix: use try/except in get_choices to preserve hashable
 key types; add tests

---
 rest_framework/relations.py | 11 ++++++++---
 tests/test_relations.py     | 35 +++++++++++++++++++++++++++++++++++
 2 files changed, 43 insertions(+), 3 deletions(-)

diff --git a/rest_framework/relations.py b/rest_framework/relations.py
index 0f3c0cd037..47452cd6f4 100644
--- a/rest_framework/relations.py
+++ b/rest_framework/relations.py
@@ -198,9 +198,14 @@ def get_choices(self, cutoff=None):
         if cutoff is not None:
             queryset = queryset[:cutoff]
 
-        return {
-            str(self.to_representation(item)): self.display_value(item) for item in queryset
-        }
+        result = {}
+        for item in queryset:
+            value = self.to_representation(item)
+            try:
+                result[value] = self.display_value(item)
+            except TypeError:
+                result[str(value)] = self.display_value(item)
+        return result
 
     @property
     def choices(self):
diff --git a/tests/test_relations.py b/tests/test_relations.py
index b9ab157896..7a6d555ec6 100644
--- a/tests/test_relations.py
+++ b/tests/test_relations.py
@@ -509,6 +509,41 @@ def test_get_value_multi_dictionary_partial(self):
         assert empty == self.field.get_value(mvd)
 
 
+class TestRelatedFieldGetChoicesUnhashable(APISimpleTestCase):
+    def test_get_choices_with_unhashable_to_representation(self):
+        """get_choices() should not raise TypeError when to_representation returns an unhashable type."""
+        queryset = MockQueryset([
+            MockObject(pk=1, name='foo'),
+            MockObject(pk=2, name='bar'),
+        ])
+
+        class DictRelatedField(serializers.RelatedField):
+            def to_representation(self, obj):
+                return {'id': obj.pk, 'name': obj.name}
+
+            def to_internal_value(self, data):
+                pass
+
+        field = DictRelatedField(read_only=True)
+        field.queryset = queryset
+        choices = field.get_choices()
+        assert choices == {
+            "{'id': 1, 'name': 'foo'}": 'MockObject name=foo, pk=1',
+            "{'id': 2, 'name': 'bar'}": 'MockObject name=bar, pk=2',
+        }
+
+    def test_get_choices_with_hashable_to_representation_unchanged(self):
+        """get_choices() should return original type keys when to_representation returns a hashable."""
+        queryset = MockQueryset([
+            MockObject(pk=1, name='foo'),
+            MockObject(pk=2, name='bar'),
+        ])
+        field = serializers.PrimaryKeyRelatedField(queryset=queryset)
+        choices = field.get_choices()
+        # Keys should remain ints (not stringified), preserving existing behavior
+        assert list(choices.keys()) == [1, 2]
+
+
 class TestHyperlink:
     def setup_method(self):
         self.default_hyperlink = serializers.Hyperlink('http://example.com', 'test')

From 4ac2a10b38cab37828bed12e7a0097f0750f1051 Mon Sep 17 00:00:00 2001
From: LeSingh1 <sshaurya914@gmail.com>
Date: Fri, 10 Jul 2026 07:35:34 -0700
Subject: [PATCH 3/3] fix: correct expected display_value in get_choices
 unhashable test

MockObject.__str__ wraps its representation in angle brackets, so
display_value() returns '<MockObject ...>'. Align the expected choices
mapping with that output so the test passes.
---
 tests/test_relations.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/test_relations.py b/tests/test_relations.py
index 7a6d555ec6..b72b0266b5 100644
--- a/tests/test_relations.py
+++ b/tests/test_relations.py
@@ -528,8 +528,8 @@ def to_internal_value(self, data):
         field.queryset = queryset
         choices = field.get_choices()
         assert choices == {
-            "{'id': 1, 'name': 'foo'}": 'MockObject name=foo, pk=1',
-            "{'id': 2, 'name': 'bar'}": 'MockObject name=bar, pk=2',
+            "{'id': 1, 'name': 'foo'}": '<MockObject name=foo, pk=1>',
+            "{'id': 2, 'name': 'bar'}": '<MockObject name=bar, pk=2>',
         }
 
     def test_get_choices_with_hashable_to_representation_unchanged(self):