fields

class polyfactory.fields.WrappedCallable

Bases: TypedDict

A ref storing a callable. This class is a utility meant to prevent binding of methods.

class polyfactory.fields.Require

Bases: object

A factory field that marks an attribute as a required build-time kwarg.

class polyfactory.fields.NeverNone

Bases: object

A factory field that marks as always generated, even if it’s an optional.

class polyfactory.fields.AlwaysNone

Bases: object

A factory field that marks as never generated, setting the value to None, regardless of if it’s an optional field

This is distinct from Ignore() which does not set a value for a field at all. If Ignore() is used and a default value for a field is not set on the underlying model, then the field will not be set at all.

class polyfactory.fields.Ignore

Bases: object

A factory field that marks an attribute as ignored. This prevents the factory generating any value for this field.

If you are using this on a pydantic model this will cause the field to be omitted from the resulting pydantic model if there is no default value set for the pydantic field.

class polyfactory.fields.Use

Bases: Generic[P, T]

Factory field used to wrap a callable.

The callable will be invoked whenever building the given factory attribute.

__init__(fn: ~typing.Callable[[~P], ~polyfactory.fields.T], *args: ~typing.~P, **kwargs: ~typing.~P) → None

Wrap a callable.

Parameters:

• fn – A callable to wrap.

• args – Any args to pass to the callable.

• kwargs – Any kwargs to pass to the callable.

to_value() → T

Invoke the callable.

Returns:

The output of the callable.

class polyfactory.fields.PostGenerated

Bases: object

Factory field that allows generating values after other fields are generated by the factory.

__init__(fn: Callable, *args: Any, **kwargs: Any) → None

Designate field as post-generated.

Parameters:

• fn – A callable.

• args – Args for the callable.

• kwargs – Kwargs for the callable.

to_value(name: str, values: dict[str, Any]) → Any

Invoke the post-generation callback passing to it the build results.

Parameters:

• name – Field name.

• values – Generated values.

Returns:

An arbitrary value.

class polyfactory.fields.Fixture

Bases: object

Factory field to create a pytest fixture from a factory.

__init__(fixture: Callable, size: int | None = None, **kwargs: Any) → None

Create a fixture from a factory.

Parameters:

• fixture – A factory that was registered as a fixture.

• size – Optional batch size.

• kwargs – Any build kwargs.

to_value() → Any

Call the factory’s build or batch method.

Raises:

ParameterException

Returns:

The build result.