Automating Unit Test Generation for Backend Code

Scenario

You have a Python backend application with a module that contains business logic functions. You want to generate unit tests for these functions to ensure they work as expected. The project structure is as follows:

backend_app/
├── business_logic.py
└── tests/
└── test_business_logic.py

Contents of business_logic.py:

# business_logic.py

def calculate_discount(price, customer_type):
    if customer_type == 'VIP':
        return price * 0.8  # 20% discount
    elif customer_type == 'Loyal':
        return price * 0.9  # 10% discount
    else:
        return price  # No discount

def is_eligible_for_loan(age, income, credit_score):
    if age < 18:
        return False
    if income < 20000:
        return False
    if credit_score < 600:
        return False
    return True

Prompt to Use in Fynix

"Please generate unit tests for the functions calculate_discount and is_eligible_for_loan in business_logic.py. The tests should cover various scenarios, including edge cases, and use Python's built-in unittest framework. Provide assertions to verify that the functions return the expected results for different inputs. Ensure that the generated tests can be run directly and include any necessary imports."

Tip: You can use /test instead of just writing test.

Expected Output from Fynix

Contents of tests/test_business_logic.py:

# tests/test_business_logic.py

import unittest
from backend_app.business_logic import calculate_discount, is_eligible_for_loan

class TestBusinessLogic(unittest.TestCase):

    def test_calculate_discount_vip_customer(self):
        price = 100
        customer_type = 'VIP'
        expected = 80  # 20% discount
        result = calculate_discount(price, customer_type)
        self.assertEqual(result, expected)

    def test_calculate_discount_loyal_customer(self):
        price = 100
        customer_type = 'Loyal'
        expected = 90  # 10% discount
        result = calculate_discount(price, customer_type)
        self.assertEqual(result, expected)

    def test_calculate_discount_regular_customer(self):
        price = 100
        customer_type = 'Regular'
        expected = 100  # No discount
        result = calculate_discount(price, customer_type)
        self.assertEqual(result, expected)

    def test_is_eligible_for_loan_underage(self):
        age = 17
        income = 50000
        credit_score = 700
        result = is_eligible_for_loan(age, income, credit_score)
        self.assertFalse(result)

    def test_is_eligible_for_loan_low_income(self):
        age = 25
        income = 15000
        credit_score = 700
        result = is_eligible_for_loan(age, income, credit_score)
        self.assertFalse(result)

    def test_is_eligible_for_loan_low_credit_score(self):
        age = 30
        income = 50000
        credit_score = 550
        result = is_eligible_for_loan(age, income, credit_score)
        self.assertFalse(result)

    def test_is_eligible_for_loan_eligible(self):
        age = 30
        income = 50000
        credit_score = 700
        result = is_eligible_for_loan(age, income, credit_score)
        self.assertTrue(result)

if __name__ == '__main__':
    unittest.main()

Instructions to Run and See Output

1. Project Structure Confirmation: Ensure your project structure matches the following:

backend_app/
├── business_logic.py
└── tests/
    └── test_business_logic.py

2. Copy the Code:

   • Place the provided business_logic.py in backend_app/.
   • Place the generated test_business_logic.py in backend_app/tests/.

3. Run the Unit Tests:

   • Navigate to the backend_app directory in your terminal:

cd backend_app
111

    * Run the tests using the unittest framework:

```bash
python -m unittest tests/test_business_logic.py

4. Expected Output:

You should see output similar to:

.......
----------------------------------------------------------------------
Ran 7 tests in 0.001s

OK

Note: Replace backend_app, business_logic.py, and function names with your actual project names and functions when using the prompt in your real work scenarios.