m2m

tests.py

from django.db import transaction
from django.test import TestCase

from users.models import User
from . import models


class MyTestCase(TestCase):
    def test_create_expense(self):
        user = User.objects.create(email="[email protected]")
        tags = [
            models.Tag.objects.create(title="tag #{}".format(i+1)) for i in range(10)
        ]

        with transaction.atomic():
            expense = models.Expense.objects.create(
                user=user,
                amount=3,
                details="ASdasda"
            )
            expense.tags = tags[2:6]

        expense.tags.add(tags[8])
        expense.tags.clear()