[3.15] Add functions related to UniqueConstraint (#591)

* [3.15] Add functions related to UniqueConstraint

* [3.15] Fix to the correct type

Author: JaeHyuckSa

rest_framework-stubs/serializers.pyi

@@ -253,6 +253,7 @@ class ModelSerializer(Serializer, BaseSerializer[_MT]):
         self, kwargs: MutableMapping[str, Any], extra_kwargs: MutableMapping[str, Any]
     ) -> MutableMapping[str, Any]: ...
     def get_extra_kwargs(self) -> dict[str, Any]: ...
+    def get_unique_together_constraints(self, model: _MT) -> Iterator[tuple[set[tuple[str, ...]], Manager[_MT]]]: ...
     def get_uniqueness_extra_kwargs(
         self, field_names: Iterable[str], declared_fields: Mapping[str, Field], extra_kwargs: dict[str, Any]
     ) -> tuple[dict[str, Any], dict[str, HiddenField]]: ...

rest_framework-stubs/utils/field_mapping.pyi

@@ -1,8 +1,9 @@
 from _typeshed import Incomplete
 from collections.abc import MutableMapping, Sequence
-from typing import Any, Generic, TypeVar
+from typing import Any, Generic, Iterator, TypeVar
 
 from django.db import models
+from rest_framework.validators import UniqueValidator
 
 NUMERIC_FIELD_TYPES: Sequence[type[models.Field]]
 
@@ -17,6 +18,7 @@ class ClassLookupDict(Generic[_K, _V]):
 
 def needs_label(model_field: models.Field, field_name: str) -> bool: ...
 def get_detail_view_name(model: models.Model) -> str: ...
+def get_unique_validators(field_name: str, model_field: models.Field) -> Iterator[UniqueValidator]: ...
 def get_field_kwargs(field_name: str, model_field: models.Field) -> dict[str, Any]: ...
 def get_relation_kwargs(field_name: str, relation_info: Incomplete) -> dict[str, Any]: ...
 def get_nested_relation_kwargs(relation_info: Incomplete) -> dict[str, Any]: ...

scripts/stubtest/allowlist_todo.txt

@@ -135,7 +135,3 @@ rest_framework.validators.Validator
 rest_framework.views.APIView.metadata_class
 rest_framework.views.AsView
 rest_framework.views.GenericView
-
-# Added in 3.15:
-rest_framework.serializers.ModelSerializer.get_unique_together_constraints
-rest_framework.utils.field_mapping.get_unique_validators