Improved list generation

[hmvp]

The problem

We currently use a class (see next section) to generate random lists, with the option to override values on the items on that list.
I could not find functionality in factory_boy that matches this, however I feel that it would be very handy to have...

If this already exists I would really like to know how to do that ergonomically without a separate class...

Proposed solution

from typing import Any

import factory
from factory.random import randgen


class RandomListFactory(factory.SubFactory):
    def __init__(self, item_factory: factory.Factory, list_factory: str = "factory.ListFactory", **params: Any):
        self.item_factory = item_factory
        super().__init__(list_factory, **params)

    def evaluate(self, instance: Any, step: factory.base.builder.BuildStep, extra: dict[str, Any]) -> Any:
        size = extra.pop("size", None)
        min_items = size if (size is not None) else extra.pop("min", 1)
        max_items = size if (size is not None) else extra.pop("max", 15)
        for i in range(randgen.randint(min_items, max_items)):
            extra[str(i)] = factory.SubFactory(self.item_factory)

        return step.recurse(self.get_factory(), extra, force_sequence=step.sequence)


class GenerateMoneyFactory(factory.DictFactory):
    amount = factory.Faker("random_int")
    type = factory.Faker("random_element", elements=["Dollar", "Euro", "Rupee"])


class GeneratedWalletFactory(factory.DictFactory):
    contents = RandomListFactory(GenerateMoneyFactory)


wallet = GeneratedWalletFactory(contents__size=2, contents__0__amount=10, contents__1__type="Rupee")
print(wallet)  # prints: {'contents': [{'amount': 10, 'type': <random>}, {'amount': <random>, 'type': 'Rupee'}]}


wallet = GeneratedWalletFactory(contents__min=1, contents__max=3, contents__0__amount=10)
print(wallet)  # prints: {'contents': [{'amount': 10, 'type': <random>}, <random one or two extra items>]}

Extra notes

If you want to add this, feel free to improve it to make it more consistent with the rest of the code