Pass use_default_with_required via constructor instead of patching

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: butvinm

src/datamodel_code_generator/parser/graphql.py

@@ -386,7 +386,7 @@ def parse_field(
             validation_aliases = alias
         else:
             single_alias = alias
-        new_field = self.data_model_field_type(
+        return self.data_model_field_type(
             name=field_name,
             default=effective_default,
             data_type=final_data_type,
@@ -404,9 +404,8 @@ def parse_field(
             original_name=field_name,
             has_default=effective_has_default,
             use_serialization_alias=self.use_serialization_alias,
+            use_default_with_required=use_default_with_required,
         )
-        new_field.use_default_with_required = use_default_with_required
-        return new_field
 
     def parse_object_like(
         self,

src/datamodel_code_generator/parser/jsonschema.py

@@ -1201,6 +1201,7 @@ def get_object_field(  # noqa: PLR0913
         original_field_name: str | None,
         effective_default: Any = None,
         effective_has_default: bool | None = None,
+        use_default_with_required: bool = False,
     ) -> DataModelFieldBase:
         """Create a data model field from a JSON Schema object field."""
         default_value = effective_default if effective_has_default is not None else field.default
@@ -1251,6 +1252,7 @@ def get_object_field(  # noqa: PLR0913
             use_frozen_field=self.use_frozen_field,
             use_serialization_alias=self.use_serialization_alias,
             use_default_factory_for_optional_nested_models=self.use_default_factory_for_optional_nested_models,
+            use_default_with_required=use_default_with_required,
         )
 
     def get_data_type(self, obj: JsonSchemaObject) -> DataType:
@@ -2832,19 +2834,21 @@ def parse_object_fields(
                 required: bool = False
             else:
                 required = original_field_name in requires
-            new_field = self.get_object_field(
-                field_name=field_name,
-                field=field,
-                required=required,
-                field_type=field_type,
-                alias=alias,
-                original_field_name=original_field_name,
-                effective_default=effective_default,
-                effective_has_default=effective_has_default,
+            fields.append(
+                self.get_object_field(
+                    field_name=field_name,
+                    field=field,
+                    required=required,
+                    field_type=field_type,
+                    alias=alias,
+                    original_field_name=original_field_name,
+                    effective_default=effective_default,
+                    effective_has_default=effective_has_default,
+                    use_default_with_required=required
+                    and self.apply_default_values_for_required_fields
+                    and effective_has_default,
+                )
             )
-            if required and self.apply_default_values_for_required_fields and effective_has_default:
-                new_field.use_default_with_required = True
-            fields.append(new_field)
         return fields
 
     def parse_object(

src/datamodel_code_generator/parser/openapi.py

@@ -508,7 +508,7 @@ def _get_model_name(cls, path_name: str, method: str, suffix: str) -> str:
         camel_path_name = snake_to_upper_camel(normalized)
         return f"{camel_path_name}{method.capitalize()}{suffix}"
 
-    def parse_all_parameters(  # noqa: PLR0912, PLR0914, PLR0915
+    def parse_all_parameters(  # noqa: PLR0912, PLR0914
         self,
         name: str,
         parameters: list[ReferenceObject | ParameterObject],
@@ -551,21 +551,21 @@ def parse_all_parameters(  # noqa: PLR0912, PLR0914, PLR0915
                     class_name=reference.name,
                 )
                 effective_required = parameter.required
-                use_default_with_required = (
-                    effective_required and self.apply_default_values_for_required_fields and effective_has_default
-                )
-                new_field = self.get_object_field(
-                    field_name=field_name,
-                    field=param_schema,
-                    field_type=self.parse_item(field_name, param_schema, [*path, name, parameter_name]),
-                    original_field_name=parameter_name,
-                    required=effective_required,
-                    alias=alias,
-                    effective_default=effective_default,
-                    effective_has_default=effective_has_default,
+                fields.append(
+                    self.get_object_field(
+                        field_name=field_name,
+                        field=param_schema,
+                        field_type=self.parse_item(field_name, param_schema, [*path, name, parameter_name]),
+                        original_field_name=parameter_name,
+                        required=effective_required,
+                        alias=alias,
+                        effective_default=effective_default,
+                        effective_has_default=effective_has_default,
+                        use_default_with_required=effective_required
+                        and self.apply_default_values_for_required_fields
+                        and effective_has_default,
+                    )
                 )
-                new_field.use_default_with_required = use_default_with_required
-                fields.append(new_field)
             else:
                 data_types: list[DataType] = []
                 object_schema: JsonSchemaObject | None = None
@@ -601,48 +601,48 @@ def parse_all_parameters(  # noqa: PLR0912, PLR0914, PLR0915
                     class_name=reference.name,
                 )
                 effective_required = parameter.required
-                use_default_with_required = (
-                    effective_required and self.apply_default_values_for_required_fields and effective_has_default
-                )
                 # Handle multiple aliases (Pydantic v2 AliasChoices)
                 single_alias: str | None = None
                 validation_aliases: list[str] | None = None
                 if isinstance(alias, list):
                     validation_aliases = alias
                 else:
                     single_alias = alias
-                new_field = self.data_model_field_type(
-                    name=field_name,
-                    default=effective_default,
-                    data_type=data_type,
-                    required=effective_required,
-                    alias=single_alias,
-                    validation_aliases=validation_aliases,
-                    constraints=object_schema.model_dump(exclude_none=True)
-                    if object_schema and self.is_constraints_field(object_schema)
-                    else None,
-                    nullable=object_schema.nullable
-                    if object_schema and self.strict_nullable and object_schema.nullable is not None
-                    else (
-                        False
-                        if object_schema and self.strict_nullable and (effective_has_default or effective_required)
-                        else None
-                    ),
-                    strip_default_none=self.strip_default_none,
-                    extras=self.get_field_extras(object_schema) if object_schema else {},
-                    use_annotated=self.use_annotated,
-                    use_serialize_as_any=self.use_serialize_as_any,
-                    use_field_description=self.use_field_description,
-                    use_field_description_example=self.use_field_description_example,
-                    use_inline_field_description=self.use_inline_field_description,
-                    use_default_kwarg=self.use_default_kwarg,
-                    original_name=parameter_name,
-                    has_default=effective_has_default,
-                    type_has_null=object_schema.type_has_null if object_schema else None,
-                    use_serialization_alias=self.use_serialization_alias,
+                fields.append(
+                    self.data_model_field_type(
+                        name=field_name,
+                        default=effective_default,
+                        data_type=data_type,
+                        required=effective_required,
+                        alias=single_alias,
+                        validation_aliases=validation_aliases,
+                        constraints=object_schema.model_dump(exclude_none=True)
+                        if object_schema and self.is_constraints_field(object_schema)
+                        else None,
+                        nullable=object_schema.nullable
+                        if object_schema and self.strict_nullable and object_schema.nullable is not None
+                        else (
+                            False
+                            if object_schema and self.strict_nullable and (effective_has_default or effective_required)
+                            else None
+                        ),
+                        strip_default_none=self.strip_default_none,
+                        extras=self.get_field_extras(object_schema) if object_schema else {},
+                        use_annotated=self.use_annotated,
+                        use_serialize_as_any=self.use_serialize_as_any,
+                        use_field_description=self.use_field_description,
+                        use_field_description_example=self.use_field_description_example,
+                        use_inline_field_description=self.use_inline_field_description,
+                        use_default_kwarg=self.use_default_kwarg,
+                        original_name=parameter_name,
+                        has_default=effective_has_default,
+                        type_has_null=object_schema.type_has_null if object_schema else None,
+                        use_serialization_alias=self.use_serialization_alias,
+                        use_default_with_required=effective_required
+                        and self.apply_default_values_for_required_fields
+                        and effective_has_default,
+                    )
                 )
-                new_field.use_default_with_required = use_default_with_required
-                fields.append(new_field)
 
         if OpenAPIScope.Parameters in self.open_api_scopes and fields:
             # Using _create_data_model from parent class JsonSchemaParser