Custom markers in PyTest - Test Execution Trace

Test Overview

This test uses a custom marker to categorize a test case. It verifies that the test runs only when the marker is used and that the assertion inside the test passes.

Test Code - pytest

PyTest

import pytest

@pytest.mark.slow
def test_addition():
    result = 2 + 3
    assert result == 5

Execution Trace - 4 Steps

Step	Action	System State	Assertion	Result
1	Pytest starts test collection and identifies test_addition with custom marker 'slow'.	Test suite is ready to run tests with markers.	-	PASS
2	Pytest runs test_addition marked with @pytest.mark.slow.	Inside test_addition function, calculation 2 + 3 is performed.	-	PASS
3	Assertion checks if result equals 5.	Variable result holds value 5.	assert result == 5	PASS
4	Test test_addition completes successfully.	Test marked 'slow' passed.	-	PASS

Failure Scenario

Failing Condition: The assertion fails because the result is not equal to 5.

Execution Trace Quiz - 3 Questions

What does the custom marker '@pytest.mark.slow' do in this test?

A It categorizes the test as slow so it can be selectively run.

B It makes the test run faster.

C It skips the test automatically.

D It changes the assertion behavior.

Key Result

Using custom markers helps organize tests by categories like speed or feature, allowing selective test runs and better test management.