From a150522d14d52d6721236ae3d391b4ae0b8a936b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebasti=C3=A1n=20Ram=C3=ADrez?= <tiangolo@gmail.com>
Date: Fri, 6 Feb 2026 19:58:07 +0100
Subject: [PATCH] =?UTF-8?q?=E2=99=BB=EF=B8=8F=20Cleanup=20more,=20remove?=
 =?UTF-8?q?=20unneeded=20code?=
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---
 fastapi/_compat/v2.py         | 6 +++---
 fastapi/dependencies/utils.py | 6 +-----
 fastapi/routing.py            | 7 ++-----
 3 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/fastapi/_compat/v2.py b/fastapi/_compat/v2.py
index 766976a974..57b3d94ffc 100644
--- a/fastapi/_compat/v2.py
+++ b/fastapi/_compat/v2.py
@@ -169,11 +169,11 @@ class ModelField:
         values: dict[str, Any] = {},  # noqa: B006
         *,
         loc: tuple[Union[int, str], ...] = (),
-    ) -> tuple[Any, Union[list[dict[str, Any]], None]]:
+    ) -> tuple[Any, list[dict[str, Any]]]:
         try:
             return (
                 self._type_adapter.validate_python(value, from_attributes=True),
-                None,
+                [],
             )
         except ValidationError as exc:
             return None, _regenerate_error_with_loc(
@@ -359,7 +359,7 @@ def serialize_sequence_value(*, field: ModelField, value: Any) -> Sequence[Any]:
     return shared.sequence_annotation_to_type[origin_type](value)  # type: ignore[no-any-return,index]
 
 
-def get_missing_field_error(loc: tuple[str, ...]) -> dict[str, Any]:
+def get_missing_field_error(loc: tuple[Union[int, str], ...]) -> dict[str, Any]:
     error = ValidationError.from_exception_data(
         "Field required", [{"type": "missing", "loc": loc, "input": {}}]
     ).errors(include_url=False)[0]
diff --git a/fastapi/dependencies/utils.py b/fastapi/dependencies/utils.py
index 7ea0dee6e6..dd42371ecc 100644
--- a/fastapi/dependencies/utils.py
+++ b/fastapi/dependencies/utils.py
@@ -717,11 +717,7 @@ def _validate_value_with_model_field(
             return None, [get_missing_field_error(loc=loc)]
         else:
             return deepcopy(field.default), []
-    v_, errors_ = field.validate(value, values, loc=loc)
-    if isinstance(errors_, list):
-        return None, errors_
-    else:
-        return v_, []
+    return field.validate(value, values, loc=loc)
 
 
 def _is_json_field(field: ModelField) -> bool:
diff --git a/fastapi/routing.py b/fastapi/routing.py
index b8d1f76248..fe8d886093 100644
--- a/fastapi/routing.py
+++ b/fastapi/routing.py
@@ -277,15 +277,12 @@ async def serialize_response(
     endpoint_ctx: Optional[EndpointContext] = None,
 ) -> Any:
     if field:
-        errors = []
         if is_coroutine:
-            value, errors_ = field.validate(response_content, {}, loc=("response",))
+            value, errors = field.validate(response_content, {}, loc=("response",))
         else:
-            value, errors_ = await run_in_threadpool(
+            value, errors = await run_in_threadpool(
                 field.validate, response_content, {}, loc=("response",)
             )
-        if isinstance(errors_, list):
-            errors.extend(errors_)
         if errors:
             ctx = endpoint_ctx or EndpointContext()
             raise ResponseValidationError(