Describe the bug
When a field's type is object (dict) with additionalProperties containing an anyOf union that includes a tuple-like array schema (prefixItems + minItems/maxItems), and the field has "default": {}, the generator wraps the default with the inner union member's RootModel instead of using default_factory=dict.
Generated: default_factory=lambda: Configs({}) where Configs is a RootModel[tuple[Any]]
Expected: default_factory=dict
The {} default belongs to the outer dict type, not to the inner Configs RootModel.
To Reproduce
Example schema:
{
"openapi": "3.1.0",
"info": { "title": "Repro", "version": "0.1.0" },
"paths": {
"/test": {
"get": {
"responses": {
"200": {
"description": "OK",
"content": {
"application/json": {
"schema": { "$ref": "#/components/schemas/MyModel" }
}
}
}
}
}
}
},
"components": {
"schemas": {
"MyModel": {
"type": "object",
"properties": {
"configs": {
"additionalProperties": {
"anyOf": [
{
"prefixItems": [{}],
"type": "array",
"maxItems": 1,
"minItems": 1
},
{ "type": "number" }
]
},
"type": "object",
"default": {}
}
}
}
}
}
}Used commandline:
$ datamodel-codegen --input schema.json --output models.py --output-model-type pydantic_v2.BaseModel --use-annotated --field-constraints
Generated output:
class Configs(RootModel[tuple[Any]]):
root: Annotated[tuple[Any], Field(max_length=1, min_length=1)]
class MyModel(BaseModel):
configs: Annotated[
dict[str, Configs | float] | None,
Field(
default_factory=lambda: Configs({}),
description='Mapping of name to config',
title='Configs',
),
]Expected behavior
The default factory should match the field's outer type (dict), not the inner union member:
class MyModel(BaseModel):
configs: Annotated[
dict[str, Configs | float] | None,
Field(
default_factory=dict,
description='Mapping of name to config',
title='Configs',
),
]Version:
- OS: Linux
- Python version: 3.13
- datamodel-code-generator version: 0.55.0
Describe the bug
When a field's type is
object(dict) withadditionalPropertiescontaining ananyOfunion that includes a tuple-like array schema (prefixItems+minItems/maxItems), and the field has"default": {}, the generator wraps the default with the inner union member's RootModel instead of usingdefault_factory=dict.Generated:
default_factory=lambda: Configs({})whereConfigsis aRootModel[tuple[Any]]Expected:
default_factory=dictThe
{}default belongs to the outerdicttype, not to the innerConfigsRootModel.To Reproduce
Example schema:
{ "openapi": "3.1.0", "info": { "title": "Repro", "version": "0.1.0" }, "paths": { "/test": { "get": { "responses": { "200": { "description": "OK", "content": { "application/json": { "schema": { "$ref": "#/components/schemas/MyModel" } } } } } } } }, "components": { "schemas": { "MyModel": { "type": "object", "properties": { "configs": { "additionalProperties": { "anyOf": [ { "prefixItems": [{}], "type": "array", "maxItems": 1, "minItems": 1 }, { "type": "number" } ] }, "type": "object", "default": {} } } } } } }Used commandline:
Generated output:
Expected behavior
The default factory should match the field's outer type (
dict), not the inner union member:Version: