Summary - Mocking

Combine Mock, patch and side_effect to write a service test.

Summary - Mocking

This group covered the tools of unittest.mock. Mock produces fakes; patch swaps a real object during a test; MagicMock supports magic methods; side_effect gives sequential or exceptional behavior; assert_called_with checks calls.

The final task combines Mock, side_effect and assert_called_with: you'll build a fake service method that returns sequential responses and check the calls.

Exercise Mock + side_effect + assert combined

Import Mock from unittest.mock. Create m = Mock(); set m.side_effect = [10, 20]. Print m() and m(). Add the check m.assert_called(); print print("ok").

Show example solution

from unittest.mock import Mock

m = Mock()
m.side_effect = [10, 20]
print(m())
print(m())
m.assert_called()
print("ok")

Test yourself

What do you use for a Mock that returns different values in sequence?
- side_effect
- MagicMock
- return_value
- patch
Show answer

side_effect — side_effect cycles a list or calls a function.

Summary: call check

m = Mock()
m(7)
m.____(7)

Show answer

m = Mock()
m(7)
m.assert_called_with(7)

Match the group tools

Mock

Fake object
patch

Swaps real
MagicMock

Magic methods
side_effect

Sequential/exception

Next lesson: async/await

We Are Enhancing Your Experience

Cookie Preferences

Strictly Necessary Cookies

Analytical Cookies