মক ও ইন্টারঅ্যাকশন ভেরিফিকেশন

import unittest
from unittest.mock import Mock


def complete_order(order_id, total, email_service):
    # সঠিক বাস্তবায়ন — অর্ডার শেষে রিসিট ইমেইল সার্ভিসকে জানানো হয়
    email_service.send_receipt(order_id, total)
    return True


def complete_order_broken(order_id, total, email_service):
    # বাগ: রিসিট ইমেইল পাঠাতে ভুলে গেছে!
    return True


class OrderReceiptTests(unittest.TestCase):
    def test_correct_implementation_sends_receipt(self):
        mock_email_service = Mock()
        complete_order(101, 550, mock_email_service)
        mock_email_service.send_receipt.assert_called_once_with(101, 550)
        self.assertEqual(mock_email_service.send_receipt.call_count, 1)

    def test_broken_implementation_forgets_to_send_receipt(self):
        mock_email_service = Mock()
        complete_order_broken(101, 550, mock_email_service)
        mock_email_service.send_receipt.assert_called_once_with(101, 550)


suite = unittest.TestLoader().loadTestsFromTestCase(OrderReceiptTests)
unittest.TextTestRunner(verbosity=2).run(suite)

from unittest.mock import Mock


def complete_order_wrong_amount(order_id, total, email_service):
    # বাগ: total-এর বদলে ভুল করে 0 পাঠাচ্ছে
    email_service.send_receipt(order_id, 0)
    return True


mock_a = Mock()
complete_order(101, 550, mock_a)
print("সঠিক বাস্তবায়ন — call_count:", mock_a.send_receipt.call_count)
print("সঠিক বাস্তবায়ন — call_args:", mock_a.send_receipt.call_args)

mock_b = Mock()
complete_order_wrong_amount(101, 550, mock_b)
print("ভুল-আর্গুমেন্ট বাস্তবায়ন — call_args:", mock_b.send_receipt.call_args)

try:
    mock_b.send_receipt.assert_called_once_with(101, 550)
    print("assert_called_once_with পাস করলো (এটা হওয়ার কথা না!)")
except AssertionError:
    print("assert_called_once_with ব্যর্থ (AssertionError) — ভুল আর্গুমেন্ট ধরা পড়েছে")