Test dublyorlari - stub, mock va fake

class SmsXizmati:
    """Haqiqiy xizmat - pul turadi va internet talab qiladi."""

    def yubor(self, raqam, matn):
        raise RuntimeError("haqiqiy SMS yuborildi - testda bu bo'lmasligi kerak")


def ogohlantir(yuboruvchi, mijoz, qarz):
    if qarz <= 0:
        return False
    matn = f"Hurmatli {mijoz['ism']}, sizda {qarz} so'm qarz bor."
    yuboruvchi.yubor(mijoz["telefon"], matn)
    return True

from xabar import ogohlantir


class SoxtaYuboruvchi:
    """Spy: yuborilgan xabarlarni yozib boradi."""

    def __init__(self):
        self.yuborilganlar = []

    def yubor(self, raqam, matn):
        self.yuborilganlar.append((raqam, matn))


def test_qarzdorga_xabar_ketadi():
    yuboruvchi = SoxtaYuboruvchi()
    mijoz = {"ism": "Aziza", "telefon": "+998901234567"}

    natija = ogohlantir(yuboruvchi, mijoz, 50_000)

    assert natija is True
    assert len(yuboruvchi.yuborilganlar) == 1
    raqam, matn = yuboruvchi.yuborilganlar[0]
    assert raqam == "+998901234567"
    assert "50000 so'm" in matn


def test_qarzsiz_mijozga_xabar_ketmaydi():
    yuboruvchi = SoxtaYuboruvchi()
    mijoz = {"ism": "Bekzod", "telefon": "+998901234568"}

    natija = ogohlantir(yuboruvchi, mijoz, 0)

    assert natija is False
    assert yuboruvchi.yuborilganlar == []

pytest -q test_qolda.py

from unittest.mock import Mock

from xabar import ogohlantir


def test_mock_bilan():
    yuboruvchi = Mock()
    mijoz = {"ism": "Aziza", "telefon": "+998901234567"}

    ogohlantir(yuboruvchi, mijoz, 50_000)

    yuboruvchi.yubor.assert_called_once_with(
        "+998901234567",
        "Hurmatli Aziza, sizda 50000 so'm qarz bor.",
    )


def test_mock_chaqirilmaganini_tekshirish():
    yuboruvchi = Mock()
    mijoz = {"ism": "Bekzod", "telefon": "+998901234568"}

    ogohlantir(yuboruvchi, mijoz, 0)

    yuboruvchi.yubor.assert_not_called()


def test_mock_javob_qaytarsin():
    yuboruvchi = Mock()
    yuboruvchi.yubor.return_value = "yuborildi"

    javob = yuboruvchi.yubor("+998901234567", "salom")

    assert javob == "yuborildi"
    assert yuboruvchi.yubor.call_count == 1

pytest -q test_mock.py

def valyuta_kursi():
    # Haqiqiy kodda shu yerda tashqi xizmatga so'rov ketadi:
    #   javob = urllib.request.urlopen("https://misol.uz/kurs", timeout=5)
    #   return float(javob.read())
    # Darslikda uning chaqirilgani darhol ko'rinishi uchun xato tashlaymiz.
    raise RuntimeError("haqiqiy so'rov ketdi - testda bu bo'lmasligi kerak")


def dollarda(summa_som):
    return round(summa_som / valyuta_kursi(), 2)

import kurs


def test_dollarga_aylantirish(monkeypatch):
    monkeypatch.setattr(kurs, "valyuta_kursi", lambda: 12_500.0)

    natija = kurs.dollarda(125_000)

    assert natija == 10.0


def test_boshqa_kurs_bilan(monkeypatch):
    monkeypatch.setattr(kurs, "valyuta_kursi", lambda: 12_000.0)

    assert kurs.dollarda(120_000) == 10.0

pytest -q test_monkeypatch.py

from kurs import valyuta_kursi


def dollar_hisoboti(summa_som):
    return f"{summa_som} so'm = {round(summa_som / valyuta_kursi(), 2)} dollar"

import kurs
from hisobot import dollar_hisoboti


def test_hisobot(monkeypatch):
    monkeypatch.setattr(kurs, "valyuta_kursi", lambda: 12_500.0)

    natija = dollar_hisoboti(125_000)

    assert natija == "125000 so'm = 10.0 dollar"

pytest -q --tb=short test_notogri_patch.py

import hisobot


def test_hisobot(monkeypatch):
    monkeypatch.setattr(hisobot, "valyuta_kursi", lambda: 12_500.0)

    natija = hisobot.dollar_hisoboti(125_000)

    assert natija == "125000 so'm = 10.0 dollar"

pytest -q test_togri_patch.py

class Ombor:
    """Interfeys - haqiqiy amalga oshirish bazaga yozadi."""

    def saqla(self, mijoz):
        raise NotImplementedError

    def top(self, mijoz_id):
        raise NotImplementedError


class XotiradagiOmbor(Ombor):
    """Fake: xuddi shunday ishlaydi, lekin xotirada."""

    def __init__(self):
        self.yozuvlar = {}

    def saqla(self, mijoz):
        self.yozuvlar[mijoz["id"]] = mijoz

    def top(self, mijoz_id):
        return self.yozuvlar.get(mijoz_id)


def royxatdan_otkaz(ombor, mijoz):
    if ombor.top(mijoz["id"]) is not None:
        raise ValueError("bunday mijoz allaqachon bor")
    ombor.saqla(mijoz)
    return mijoz["id"]

import pytest

from ombor import XotiradagiOmbor, royxatdan_otkaz


def test_yangi_mijoz_saqlanadi():
    ombor = XotiradagiOmbor()

    mijoz_id = royxatdan_otkaz(ombor, {"id": 1, "ism": "Aziza"})

    assert mijoz_id == 1
    assert ombor.top(1)["ism"] == "Aziza"


def test_takroriy_mijoz_xato_beradi():
    ombor = XotiradagiOmbor()
    royxatdan_otkaz(ombor, {"id": 1, "ism": "Aziza"})

    with pytest.raises(ValueError, match="allaqachon"):
        royxatdan_otkaz(ombor, {"id": 1, "ism": "Aziza"})

pytest -q test_fake.py