Statement coverage in Testing Fundamentals - Test Execution Trace

Test Overview

This test checks if all the statements in a simple function are executed at least once. It verifies that the function returns the correct output for given inputs, ensuring full statement coverage.

Test Code - PyTest

Testing Fundamentals

def max_of_two(a, b):
    if a > b:
        return a
    else:
        return b


def test_max_of_two():
    assert max_of_two(5, 3) == 5
    assert max_of_two(2, 4) == 4
    assert max_of_two(7, 7) == 7

if __name__ == "__main__":
    test_max_of_two()

Execution Trace - 5 Steps

Step	Action	System State	Assertion	Result
1	Test starts	Test environment ready, function max_of_two defined	-	PASS
2	Call max_of_two(5, 3)	Function executes with a=5, b=3	Check if returned value == 5	PASS
3	Call max_of_two(2, 4)	Function executes with a=2, b=4	Check if returned value == 4	PASS
4	Call max_of_two(7, 7)	Function executes with a=7, b=7	Check if returned value == 7	PASS
5	All assertions passed, test ends	All statements in max_of_two executed at least once	Verify full statement coverage	PASS

Failure Scenario

Failing Condition: If one of the assertions fails because the function returns wrong value

Execution Trace Quiz - 3 Questions

What does statement coverage ensure in this test?

A All possible input values are tested

B All lines of code in the function are executed at least once

C The function runs without errors

D The function returns the same value every time

Key Result

Statement coverage helps ensure every line of code runs during testing, catching missed logic or errors in any part of the function.