Test setup helpers

[tandemdude]

Currently, it is quite confusing on how to set up a test for a command invoke method so that options can be resolved correctly. It would be nice to provide some helper functionality to make it easier for developers, and to prevent having to delve into protected fields.

[Skelmis]

I've ended using this to setup commands for usage within tests after our earlier discussions and with some minor refinement

from typing import Sequence, TypeVar, Type
from unittest import mock

import hikari
import lightbulb

T = TypeVar("T")


async def prepare_command(
    cls: Type[T],
    options: Sequence[hikari.CommandInteractionOption] = None,
) -> (T, lightbulb.Context):
    await cls.as_command_builder(
        hikari.Locale.EN_GB, lightbulb.localization_unsupported
    )
    client: lightbulb.Client = mock.Mock()
    ctx: lightbulb.Context = mock.Mock(spec=lightbulb.Context, client=client)
    if options is not None:
        ctx.options = options

    cls_instance: T = cls()
    cls_instance._set_context(ctx)  # noqa

    return cls_instance, ctx