Unit va integration: bitta funksiyaga ikki xil test

# apps/todos/services.py
from datetime import date

from apps.todos.models import Task


def group_tasks(tasks: list[Task], today: date) -> dict[str, list[Task]]:
    """Vazifalarni sanaga qarab uch guruhga ajratadi.

    E'tibor bering: bazaga tegmaydi, bugungi sanani ham o'zi olmaydi —
    hammasi tashqaridan keladi. Aynan shu ikkala qaror uni unit test
    uchun ideal qiladi.
    """
    groups = {"bugun": [], "kechikkan": [], "kelgusi": []}
    for task in tasks:
        if task.due_date is None or task.is_done:
            continue
        if task.due_date < today:
            groups["kechikkan"].append(task)
        elif task.due_date == today:
            groups["bugun"].append(task)
        else:
            groups["kelgusi"].append(task)
    return groups

# apps/todos/views.py
from django.shortcuts import render
from django.utils import timezone

from apps.todos.models import Task
from apps.todos.services import group_tasks


def dashboard(request):
    tasks = Task.objects.filter(is_done=False)
    groups = group_tasks(list(tasks), timezone.localdate())
    return render(request, "todos/dashboard.html", {"groups": groups})

# apps/todos/urls.py
from django.urls import path

from apps.todos.views import dashboard

urlpatterns = [
    path("", dashboard, name="dashboard"),
]

# config/urls.py
from django.contrib import admin
from django.urls import include, path

urlpatterns = [
    path("admin/", admin.site.urls),
    path("todos/", include("apps.todos.urls")),
]

{# apps/todos/templates/todos/dashboard.html #}
<h1>Vazifalar</h1>
{% for name, tasks in groups.items %}
  <h2>{{ name }}</h2>
  <ul>
    {% for task in tasks %}<li>{{ task.title }}</li>{% empty %}<li>—</li>{% endfor %}
  </ul>
{% endfor %}

# apps/todos/tests/test_services.py
from datetime import date

from apps.todos.models import Task
from apps.todos.services import group_tasks

BUGUN = date(2026, 8, 16)


def make_task(due):
    # saqlanmagan obyekt — bazasiz, shuning uchun django_db belgisi ham kerak emas
    return Task(title="ish", due_date=due)


def test_uch_guruh_togri_ajratiladi():
    tasks = [
        make_task(date(2026, 8, 15)),  # kecha  → kechikkan
        make_task(BUGUN),  # bugun  → bugun
        make_task(date(2026, 8, 20)),  # keyin  → kelgusi
    ]
    groups = group_tasks(tasks, today=BUGUN)
    assert [t.due_date for t in groups["kechikkan"]] == [date(2026, 8, 15)]
    assert len(groups["bugun"]) == 1
    assert len(groups["kelgusi"]) == 1


def test_bajarilgan_va_muddatsizlar_chiqmaydi():
    tasks = [Task(title="tayyor", due_date=BUGUN, is_done=True), Task(title="muddatsiz")]
    groups = group_tasks(tasks, today=BUGUN)
    assert groups == {"bugun": [], "kechikkan": [], "kelgusi": []}

# apps/todos/tests/test_views.py
from datetime import timedelta

import pytest
from django.utils import timezone

from apps.todos.models import Task


@pytest.mark.django_db
def test_dashboard_kechikkanlarni_korsatadi(client):
    kecha = timezone.localdate() - timedelta(days=1)
    Task.objects.create(title="Hisobot topshirish", due_date=kecha)

    response = client.get("/todos/")

    assert response.status_code == 200
    assert "Hisobot topshirish" in response.content.decode()
    assert response.context["groups"]["kechikkan"][0].title == "Hisobot topshirish"

        /  E2E  \          juda oz: brauzer orqali butun tizim
       / integr. \         o'rtacha: har muhim oqimga bittadan
      /   unit    \        ko'p: har mantiq bo'lagiga bir nechta