Use eval_type_lenient instead of try_eval_type for older Pydantic version

fastapi/_compat/__init__.py

@@ -26,7 +26,7 @@ from .v2 import Undefined as Undefined
 from .v2 import Url as Url
 from .v2 import copy_field_info as copy_field_info
 from .v2 import create_body_model as create_body_model
-from .v2 import evaluate_forwardref as evaluate_forwardref
+from .v2 import evaluate_forwardref as evaluate_forwardref  # ty: ignore[deprecated]
 from .v2 import get_cached_model_fields as get_cached_model_fields
 from .v2 import get_definitions as get_definitions
 from .v2 import get_flat_models_from_fields as get_flat_models_from_fields

fastapi/_compat/v2.py

@@ -25,9 +25,7 @@ from pydantic import ValidationError as ValidationError
 from pydantic._internal._schema_generation_shared import (  # type: ignore[attr-defined]  # ty: ignore[unused-ignore-comment]
     GetJsonSchemaHandler as GetJsonSchemaHandler,
 )
-from pydantic._internal._typing_extra import (
-    try_eval_type,  # ty: ignore[deprecated]
-)
+from pydantic._internal._typing_extra import eval_type_lenient  # ty: ignore[deprecated]
 from pydantic.fields import FieldInfo as FieldInfo
 from pydantic.json_schema import GenerateJsonSchema as _GenerateJsonSchema
 from pydantic.json_schema import JsonSchemaValue as JsonSchemaValue
@@ -40,7 +38,7 @@ from pydantic_core.core_schema import (
 
 RequiredParam = PydanticUndefined
 Undefined = PydanticUndefined
-evaluate_forwardref = try_eval_type
+evaluate_forwardref = eval_type_lenient  # ty: ignore[deprecated]
 
 
 class GenerateJsonSchema(_GenerateJsonSchema):

fastapi/dependencies/utils.py

@@ -33,7 +33,7 @@ from fastapi._compat import (
     Undefined,
     copy_field_info,
     create_body_model,
-    evaluate_forwardref,
+    evaluate_forwardref,  # ty: ignore[deprecated]
     field_annotation_is_scalar,
     field_annotation_is_scalar_sequence,
     field_annotation_is_sequence,
@@ -246,8 +246,10 @@ def get_typed_annotation(annotation: Any, globalns: dict[str, Any]) -> Any:
     if isinstance(annotation, str):
         annotation = ForwardRef(annotation)
     if isinstance(annotation, ForwardRef):
-        annotation, is_evaluated = evaluate_forwardref(annotation, globalns, globalns)  # ty: ignore[deprecated]
-        if not is_evaluated:
+        annotation = evaluate_forwardref(annotation, globalns, globalns)  # ty: ignore[deprecated]
+        # eval_type_lenient returns the ForwardRef unchanged when resolution
+        # fails, so a ForwardRef result means the type could not be resolved.
+        if isinstance(annotation, ForwardRef):
             raise NameError(
                 f"Could not resolve annotation {annotation.__forward_arg__!r}. "
                 f"Make sure the type is defined or imported before it is used "