Condition coverage in Testing Fundamentals - Build an Automation Script

Test condition coverage for a function with multiple conditions

Preconditions (2)

Step 1: Call the function with inputs (True, True)

Step 2: Call the function with inputs (True, False)

Step 3: Call the function with inputs (False, True)

Step 4: Call the function with inputs (False, False)

Step 5: Verify that each condition in the function has been evaluated to both True and False at least once

✅ Expected Result: All conditions inside the function have been tested for both True and False values, ensuring condition coverage.

Automation Requirements - pytest

Assertions Needed:

Assert the function returns expected output for each input combination

Assert that all conditions in the function are exercised with True and False values

Best Practices:

Use parameterized tests to cover all input combinations

Keep tests simple and focused on one function

Use clear and descriptive test names

Automated Solution

Testing Fundamentals

import pytest

# Function with multiple conditions to test

def check_conditions(a: bool, b: bool) -> str:
    if a and b:
        return "Both True"
    elif a and not b:
        return "A True, B False"
    elif not a and b:
        return "A False, B True"
    else:
        return "Both False"

# Parameterized test to cover all condition combinations
@pytest.mark.parametrize("a,b,expected", [
    (True, True, "Both True"),
    (True, False, "A True, B False"),
    (False, True, "A False, B True"),
    (False, False, "Both False")
])
def test_check_conditions(a, b, expected):
    result = check_conditions(a, b)
    assert result == expected, f"Expected {expected} but got {result}"

The function check_conditions has two boolean inputs and multiple conditions combined with and and not. To achieve condition coverage, we must test all possible True/False values for each condition.

The test uses pytest.mark.parametrize to run the test function four times with all combinations of a and b. Each test asserts the function returns the expected string for that input.

This ensures each condition (a and b) is evaluated as True and False at least once, fulfilling condition coverage requirements.

Common Mistakes - 3 Pitfalls

Testing only some input combinations instead of all

Using print statements instead of assertions

Hardcoding expected outputs without understanding conditions

Bonus Challenge

Now add data-driven testing with 3 different sets of boolean inputs and expected outputs using pytest parameterize.

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