How can I use unittest.mock for advanced testing scenarios?

How can I use unittest.mock for advanced testing scenarios?

You can use unittest.mock to create complex test cases by mocking objects, methods, and even entire classes. What specific scenario do you have in mind?

I want to mock a database call in my tests. How can I do that?

You can use unittest.mock.patch to replace the database call with a mock object. This allows you to simulate different responses without hitting the actual database.

Can you show me an example of how to implement that?

Sure! Here's a simple example:

from unittest.mock import patch

@patch('your_module.database_call')
def test_function(mock_db_call):
    mock_db_call.return_value = 'mocked data'
    result = your_function()
    assert result == 'expected result'

What if I need to assert that the database call was made?

You can use mock_db_call.assert_called_once() to ensure that the mock was called exactly once during the test.