How do I test decorators in Python?

How do I test decorators in Python?

To test decorators in Python, you can use the unittest framework. You can create a test case that applies the decorator to a function and then checks the output.

Can you show me an example of a simple decorator and how to test it?

Sure! Here's a simple decorator that adds 1 to a number:

def add_one(func):
    def wrapper(*args, **kwargs):
        return func(*args, **kwargs) + 1
    return wrapper

To test it, you can use unittest like this:

import unittest

class TestAddOneDecorator(unittest.TestCase):
    @add_one
    def return_five(self):
        return 5

    def test_add_one(self):
        self.assertEqual(self.return_five(), 6)

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

What if my decorator takes arguments?

If your decorator takes arguments, you need to create a nested function. Here's an example:

def repeat(num_times):
    def decorator_repeat(func):
        def wrapper(*args, **kwargs):
            for _ in range(num_times):
                func(*args, **kwargs)
        return wrapper
    return decorator_repeat