Type annotation falls back to Any if property schema is partially overwridden

[simontaurus]

Describe the bug
Importing a schema and partial overwrite it (e.g., set a different default value) leads to lost type information

To Reproduce

schemaA

{
    "type": "object",
    "title": "SchemaA",
    "properties": {
        "test": {
            "title": "test",
            "type": "string",
            "default": "default_value1"
        }
    }
}

schemaB.json

{
    "allOf": [
        {
            "$ref": "SchemaA.json"
        }
    ],
    "type": "object",
    "title": "SchemaB",
    "properties": {
        "test": {
            "default": "default_value2"
        }
    }
}

Used commandline:

$ datamodel-codegen --input schemaB.json --output model.py

Result model.py: type of test in SchemaB is resetted to Any

class SchemaA(BaseModel):
    test: Optional[str] = Field('default_value1', title='test')

class SchemaB(SchemaA):
    test: Optional[Any] = 'default_value2'

Expected behavior
type of test in SchemaB is still str

class SchemaA(BaseModel):
    test: Optional[str] = Field('default_value1', title='test')

class SchemaB(SchemaA):
    test: Optional[str] = 'default_value2'

Version:

• OS: Windows 10
• Python version: 3.11 | 3.9
• datamodel-code-generator version: 0.25.6 | 0.26.0

[koxudaxi]

The type annotation issue (falling back to Any) has been fixed in PR #2614. However, merging default values in allOf is undefined behavior per JSON Schema spec, so the current output is expected.
Thnank you!!

[simontaurus]

@koxudaxi Sorry to bother you again, but there's another edge-case:

Overriding any annotation in an ìtem schema (here: setting a title) bot not repeating the type:

{
    "$defs": {
        "Thing": {
            "title": "Thing",
            "type": "object",
            "required": [
                "type",
                "name"
            ],
            "properties": {
                "type": {
                    "type": "string",
                    "default": "playground:Thing",
                    "options": {
                        "hidden": true
                    }
                },
                "type_list": {
                    "type": "array",
                    "default": [
                        "playground:Thing"
                    ],
                    "items": {
                        "type": "string",
                        "options": {
                            "hidden": true
                        }
                    }
                }
            }
        }
    },
    "allOf": [
        {
            "$ref": "#/$defs/Thing"
        }
    ],
    "title": "Person",
    "type": "object",
    "required": [
        "name"
    ],
    "properties": {
        "type": {
            "$comment": "Already defined in playground:Thing -> we override just the default",
            "default": "playground:Person"
        },
        "type_list": {
            "default": [
                "playground:Person"
            ],
            "items": {
                "title": "A type entry" # just set an annotation here. Not repeating "type": "string"
            }
        }
    }
}

still produces

class Thing(BaseModel):
    type: str
    type_list: Optional[List[str]] = ['playground:Thing']

class Person(Thing):
    type: Optional[str] = 'playground:Person'
    type_list: Optional[List[Any]] = ['playground:Person'] # should be 'Optional[List[str]]'

(example taken from #2645)

[simontaurus]

@koxudaxi sorry again but still spotting an issue of the class hierarchy is deeper (> 1 superclass)

This schema

{
    "$defs": {
        "Entity": {
            "title": "Entity",
            "type": "object",
            "required": [
                "type"
            ],
            "properties": {
                "type": { # initial definition
                    "type": "string",
                    "default": "playground:Entity"
                }
            }
        },
        "Thing": {
            "allOf": [
                {
                    "$ref": "#/$defs/Entity"
                }
            ],
            "title": "Thing",
            "type": "object",
            "required": [
                "type",
                "name"
            ],
            "properties": {
                "type": { # partial override (1)
                    "default": "playground:Thing",
                    "options": {
                        "hidden": true
                    }
                },
                "name": {
                    "type": "string",
                    "description": "The things name",
                    "minLength": 1,
                    "default": "A Thing"
                }
            }
        }
    },
    "allOf": [
        {
            "$ref": "#/$defs/Thing"
        }
    ],
    "title": "Person",
    "type": "object",
    "properties": {
        "type": { # partial override (2)
            "$comment": "Already defined in playground:Thing -> we override just the default",
            "default": "playground:Person"
        }
    }
}

generates again

type: Any

class Entity(BaseModel):
    type: str


class Thing(Entity):
    type: str
    name: constr(min_length=1) = Field(..., description='The things name')


class Person(Thing):
    type: Any | None = 'playground:Person'

[github-actions]

📢 Related PR Released: 0.51.0

PR #2861, which references this issue, has been released. See the release notes for details.

Note: This issue was not explicitly closed by the PR.