From adfb5b520e5c50d094893e8f754339fc5400d42f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebasti=C3=A1n=20Ram=C3=ADrez?= <tiangolo@gmail.com>
Date: Sat, 27 Dec 2025 01:13:03 +0100
Subject: [PATCH] =?UTF-8?q?=E2=99=BB=EF=B8=8F=20Refactor=20check=20in=20js?=
 =?UTF-8?q?onable=5Fencoder?=
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---
 fastapi/encoders.py | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/fastapi/encoders.py b/fastapi/encoders.py
index b2be91bd6..eac153035 100644
--- a/fastapi/encoders.py
+++ b/fastapi/encoders.py
@@ -223,11 +223,6 @@ def jsonable_encoder(
         include = set(include)
     if exclude is not None and not isinstance(exclude, (set, dict)):
         exclude = set(exclude)
-    if is_pydantic_v1_model_instance(obj):
-        raise PydanticV1NotSupportedError(
-            "pydantic.v1 models are no longer supported by FastAPI."
-            f" Please update the model {obj!r}."
-        )
     if isinstance(obj, BaseModel):
         obj_dict = _model_dump(
             obj,  # type: ignore[arg-type]
@@ -325,7 +320,11 @@ def jsonable_encoder(
     for encoder, classes_tuple in encoders_by_class_tuples.items():
         if isinstance(obj, classes_tuple):
             return encoder(obj)
-
+    if is_pydantic_v1_model_instance(obj):
+        raise PydanticV1NotSupportedError(
+            "pydantic.v1 models are no longer supported by FastAPI."
+            f" Please update the model {obj!r}."
+        )
     try:
         data = dict(obj)
     except Exception as e: