From f0059dd4db8d3f78e47386630a00868c80bada80 Mon Sep 17 00:00:00 2001
From: Viicos <65306057+Viicos@users.noreply.github.com>
Date: Tue, 28 Nov 2023 18:51:04 +0100
Subject: [PATCH] Explicitly raise an error if field names clashes with types

---
 pydantic/fields.py   |  8 ++++++++
 tests/test_fields.py | 14 ++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/pydantic/fields.py b/pydantic/fields.py
index 849215b3a1..e93a9aa270 100644
--- a/pydantic/fields.py
+++ b/pydantic/fields.py
@@ -321,6 +321,14 @@ class MyModel(pydantic.BaseModel):
         Returns:
             A field object with the passed values.
         """
+
+        if annotation is default:
+            raise RuntimeError(
+                'Error when building FieldInfo from annotated attribute. '
+                "Make sure you don't have any field name clashing with a type annotation "
+                '(e.g. `date: date = Field(None)`).'
+            )
+
         final = False
         if _typing_extra.is_finalvar(annotation):
             final = True
diff --git a/tests/test_fields.py b/tests/test_fields.py
index 0220dce853..6f84388ee5 100644
--- a/tests/test_fields.py
+++ b/tests/test_fields.py
@@ -17,6 +17,20 @@ def test_field_info_annotation_keyword_argument():
     assert e.value.args == ('"annotation" is not permitted as a Field keyword argument',)
 
 
+def test_field_info_annotated_attribute_name_clashing():
+    """This tests that `FieldInfo.from_annotated_attribute` will raise a `RuntimeError` if attribute names clashes
+    with a type.
+    """
+
+    with pytest.raises(RuntimeError):
+
+        class SubModel(BaseModel):
+            a: int = 1
+
+        class Model(BaseModel):
+            SubModel: SubModel = Field()
+
+
 def test_init_var_field():
     @pydantic.dataclasses.dataclass
     class Foo: