Grouping related tests in PyTest - Build an Automation Script

Group related tests for arithmetic operations

Preconditions (2)

Step 1: Create a test class named TestArithmetic

Step 2: Inside the class, write three test methods: test_addition, test_subtraction, test_multiplication

Step 3: In test_addition, assert that 2 + 3 equals 5

Step 4: In test_subtraction, assert that 5 - 2 equals 3

Step 5: In test_multiplication, assert that 3 * 4 equals 12

Step 6: Run pytest on the test_arithmetic.py file

✅ Expected Result: All three tests run together as part of the TestArithmetic group and pass successfully

Automation Requirements - pytest

Assertions Needed:

Assert equality of arithmetic results using assert statements

Best Practices:

Group related tests inside a test class

Use clear and descriptive test method names

Keep tests independent and simple

Automated Solution

PyTest

import pytest

class TestArithmetic:
    def test_addition(self):
        assert 2 + 3 == 5

    def test_subtraction(self):
        assert 5 - 2 == 3

    def test_multiplication(self):
        assert 3 * 4 == 12

This code defines a test class TestArithmetic to group related arithmetic tests.

Each test method checks one operation using simple assert statements.

Grouping tests in a class helps organize them logically and run them together.

Running pytest on this file will discover and run all three tests, showing clear pass/fail results.

Common Mistakes - 3 Pitfalls

Writing multiple unrelated tests as standalone functions without grouping

Using unclear test method names like test1, test2

Combining multiple assertions in one test method for different operations

Bonus Challenge

Now add a test for division inside the TestArithmetic class with inputs 10 and 2, asserting the result is 5

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