PydanticModelField

This class represents a field within a Pydantic model and provides utilities for managing its metadata and type information during static analysis. It supports operations such as converting fields into method arguments, expanding complex types, and serializing field data for persistence. The class is designed to integrate with type-checking plugins to handle features like aliases, default values, and generic type inheritance.

Attributes

Attribute	Type	Description
name	str	The original name of the field as defined in the Pydantic model class.
alias	`str	None`
is_frozen	bool	Indicates whether the field is immutable and cannot be modified after the model is initialized.
has_dynamic_alias	bool	Indicates whether the field's alias is determined dynamically at runtime rather than being a static string.
has_default	bool	Indicates whether the field has a default value or a default factory assigned to it.
strict	`bool	None`
line	int	The line number in the source code where the field is defined for error reporting and mapping.
column	int	The column number in the source code where the field definition begins.
type	`Type	None`
info	TypeInfo	The TypeInfo object representing the Pydantic model class that contains this field.

---

Constructor

Signature

def PydanticModelField(
    name: str,
    alias: str | None,
    is_frozen: bool,
    has_dynamic_alias: bool,
    has_default: bool,
    strict: bool | None,
    line: int,
    column: int,
    type: Type | None,
    info: TypeInfo
) - > null

Parameters

Name	Type	Description
name	str	The name of the field.
alias	`str	None`
is_frozen	bool	Indicates if the field is immutable.
has_dynamic_alias	bool	Indicates if the field has a dynamically generated alias.
has_default	bool	Indicates if the field has a default value.
strict	`bool	None`
line	int	The line number where the field is defined in the source code.
column	int	The column number where the field is defined in the source code.
type	`Type	None`
info	TypeInfo	The TypeInfo object associated with the model.

---

Signature

def PydanticModelField(
    name: string,
    alias: string | null,
    is_frozen: boolean,
    has_dynamic_alias: boolean,
    has_default: boolean,
    strict: boolean | null,
    line: integer,
    column: integer,
    type: Type | null,
    info: TypeInfo
)

Parameters

Name	Type	Description
name	string	The Python attribute name of the field.
alias	`string	null`
is_frozen	boolean	Indicates whether the field is immutable after model instantiation.
has_dynamic_alias	boolean	Indicates if the field's alias is determined at runtime rather than statically defined.
has_default	boolean	Indicates if the field has a default value or a default factory.
strict	`boolean	null`
line	integer	The source code line number where the field is defined.
column	integer	The source code column offset where the field is defined.
type	`Type	null`
info	TypeInfo	The mypy TypeInfo of the class that owns this field.

---

Methods

---

to_argument()

@classmethod
def to_argument(
    current_info: TypeInfo,
    typed: boolean,
    model_strict: boolean,
    force_optional: boolean,
    use_alias: boolean,
    api: SemanticAnalyzerPluginInterface,
    force_typevars_invariant: boolean,
    is_root_model_root: boolean
) - > Argument

Based on mypy.plugins.dataclasses.DataclassAttribute.to_argument.

Parameters

Name	Type	Description
current_info	TypeInfo	The TypeInfo of the model currently being analyzed.
typed	boolean	Whether to include explicit type annotations in the generated argument.
model_strict	boolean	The default strictness setting of the parent model to use if the field doesn't specify one.
force_optional	boolean	If true, forces the argument to be treated as optional regardless of default values.
use_alias	boolean	Whether to use the field's alias as the argument name instead of the attribute name.
api	SemanticAnalyzerPluginInterface	The mypy semantic analyzer interface for type lookups.
force_typevars_invariant	boolean	Whether to force type variables to be invariant to avoid variance errors in method signatures.
is_root_model_root	boolean	Indicates if this field represents the 'root' field of a Pydantic RootModel.

Returns

Type	Description
Argument	A mypy Argument object suitable for inclusion in a generated method signature like init.

---

expand_type()

@classmethod
def expand_type(
    current_info: TypeInfo,
    api: SemanticAnalyzerPluginInterface,
    force_typevars_invariant: boolean,
    include_root_type: boolean
) - > Type | null

Based on mypy.plugins.dataclasses.DataclassAttribute.expand_type.

Parameters

Name	Type	Description
current_info	TypeInfo	The TypeInfo used as the context for expanding generic type variables.
api	SemanticAnalyzerPluginInterface	The mypy semantic analyzer interface used to access options like strict_optional.
force_typevars_invariant	boolean	If true, modifies type variables to be invariant during expansion.
include_root_type	boolean	If true, allows the type to be a Union of the model and its root type for Pydantic RootModels.

Returns

Type	Description
`Type	null`

---

to_var()

@classmethod
def to_var(
    current_info: TypeInfo,
    api: SemanticAnalyzerPluginInterface,
    use_alias: boolean,
    force_typevars_invariant: boolean
) - > Var

Based on mypy.plugins.dataclasses.DataclassAttribute.to_var.

Parameters

Name	Type	Description
current_info	TypeInfo	The TypeInfo used for type expansion context.
api	SemanticAnalyzerPluginInterface	The mypy semantic analyzer interface.
use_alias	boolean	Whether to name the variable using the field's alias.
force_typevars_invariant	boolean	Whether to force invariance on type variables during type expansion.

Returns

Type	Description
Var	A mypy Var object representing the field as a class variable.

---

serialize()

@classmethod
def serialize() - > JsonDict

Based on mypy.plugins.dataclasses.DataclassAttribute.serialize.

Returns

Type	Description
JsonDict	A dictionary representation of the field metadata for mypy caching.

---

deserialize()

@classmethod
def deserialize(
    info: TypeInfo,
    data: JsonDict,
    api: SemanticAnalyzerPluginInterface
) - > [PydanticModelField](../v1/mypy/pydanticmodelfield.md?sid=pydantic_v1_mypy_pydanticmodelfield)

Based on mypy.plugins.dataclasses.DataclassAttribute.deserialize.

Parameters

Name	Type	Description
info	TypeInfo	The TypeInfo of the class owning this field.
data	JsonDict	The serialized field data.
api	SemanticAnalyzerPluginInterface	The mypy semantic analyzer interface used to fix up types during deserialization.

Returns

Type	Description
[PydanticModelField](../v1/mypy/pydanticmodelfield.md?sid=pydantic_v1_mypy_pydanticmodelfield)	A new instance of PydanticModelField reconstructed from the serialized data.

---

expand_typevar_from_subtype()

@classmethod
def expand_typevar_from_subtype(
    sub_type: TypeInfo,
    api: SemanticAnalyzerPluginInterface
) - > null

Expands type vars in the context of a subtype when an attribute is inherited from a generic super type.

Parameters

Name	Type	Description
sub_type	TypeInfo	The TypeInfo of the inheriting subtype used to map generic parameters.
api	SemanticAnalyzerPluginInterface	The mypy semantic analyzer interface.

Returns

Type	Description
null	None

---