import unittest
import importlib

def _dynamic_test(test_case, condition, success_message, failure_message):
    if condition:
        test_case._testMethodName = success_message
        test_case.assertTrue(True, success_message)
    else:
        test_case._testMethodName = failure_message
        test_case.fail(failure_message)


class TestRegisterUser(unittest.TestCase):
    def setUp(self):
        """Reset users_db before each test"""
        import user_code
        user_code.users_db.clear()

    def test_successful_registration(self):
        import user_code
        try:
            result = user_code.register_user(
                username="Test",
                email="test@example.com",
                age=18
            )
            expected_output = "User Test registered successfully!"
            condition = result == expected_output
            failure_message = (
                "The success message should use the provided `username` parameter. "
                f"For input ('Test', 'test@example.com', 18), expected "
                f"`{expected_output}`, but got `{result}`."
            )
        except AttributeError:
            condition = False
            failure_message = "The function `register_user` is not defined."

        _dynamic_test(
            self,
            condition,
            "User is registered successfully with valid input.",
            failure_message
        )

    def test_user_count_after_registration(self):
        import user_code
        try:
            user_code.register_user("Test", "test@example.com", 18)
            condition = len(user_code.users_db) == 1
            failure_message = (
                "After one successful registration, `users_db` should contain exactly one user."
            )
        except AttributeError:
            condition = False
            failure_message = "The function `register_user` is not defined."

        _dynamic_test(
            self,
            condition,
            "User count after registration is correct.",
            failure_message
        )

    def test_user_data_after_registration(self):
        import user_code
        try:
            user_code.register_user("Test", "test@example.com", 18)
            registered_user = user_code.users_db[0]
            condition = (
                registered_user == {
                    "username": "Test",
                    "email": "test@example.com",
                    "age": 18
                }
            )
            failure_message = (
                "The user dictionary should be created from function parameters. "
                "Expected {'username': username, 'email': email, 'age': age} "
                f"but got {registered_user}."
            )
        except Exception:
            condition = False
            failure_message = (
                "User data was not stored correctly in `users_db`."
            )

        _dynamic_test(
            self,
            condition,
            "User data is stored correctly using function parameters.",
            failure_message
        )

    def test_underage_registration(self):
        import user_code
        try:
            result = user_code.register_user("Test", "test@example.com", 16)
            expected_output = "Registration failed: age must be 18 or older."
            condition = result == expected_output and len(user_code.users_db) == 0
            failure_message = (
                "Users under 18 should not be registered and `users_db` must remain empty."
            )
        except AttributeError:
            condition = False
            failure_message = "The function `register_user` is not defined."

        _dynamic_test(
            self,
            condition,
            "Underage users are blocked correctly.",
            failure_message
        )

    def test_multiple_registrations(self):
        import user_code
        try:
            user_code.register_user("Test", "test@example.com", 18)
            user_code.register_user("Another", "another@example.com", 30)
            condition = len(user_code.users_db) == 2
            failure_message = (
                "Each call to `register_user` should append a new user to `users_db`."
            )
        except AttributeError:
            condition = False
            failure_message = "The function `register_user` is not defined."

        _dynamic_test(
            self,
            condition,
            "Multiple users can be registered successfully.",
            failure_message
        )

    def test_users_db_is_declared(self):
        import user_code
        _dynamic_test(
            self,
            hasattr(user_code, "users_db"),
            "The `users_db` variable is declared.",
            "Expected `users_db` to be declared."
        )


if __name__ == "__main__":
    unittest.main()


test_main.py

Opnå en solid forståelse af, hvordan funktioner former Python-programmering. Behersk definition og kald af funktioner, arbejde med argumenter, håndtering af returværdier samt oprettelse af fleksibel og effektiv kode ved brug af rekursion og lambda-udtryk.

Undersøg hvad funktioner er, og hvorfor de er essentielle i Python. Lær at oprette funktioner, definere argumenter, håndtere returværdier og anvende indbyggede funktioner effektivt.

Lær, hvordan positionelle og valgfrie argumenter fungerer i Python. Udarbejd fleksible funktioner, der håndterer forskellige input og øger fleksibiliteten i din kode.

Forstå hvordan man arbejder med vilkårlige og nøgleordsargumenter for at håndtere variable inputstørrelser. Lær hvordan disse teknikker gør dine funktioner mere dynamiske og organiserede.

Opdag, hvordan returværdier repræsenterer en funktions output. Lær at returnere enkelt- eller flere værdier, anvende None samt udforske generatorer for mere avanceret styring af dataflow.

Lås op for avancerede funktionskoncepter med rekursion og lambda-funktioner. Forstå hvordan rekursion løser gentagne problemer, og hvordan lambda-udtryk skaber korte, énliniers funktioner.

Udfordring: Positionelle Argumenter

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