===================================
Python Testing Quicklist(GPT)
===================================

--------------------------
1. Create a Test File
--------------------------

* Name convention: ``test_<module>.py``

  Example::

      calc.py
      test_calc.py

--------------------------
2. Import the Tools
--------------------------

.. code-block:: python

    import unittest   # built-in testing framework
    import pytest      # external framework (optional, powerful)

--------------------------
Using unittest (Built-in)
--------------------------

**Basic Structure**

.. code-block:: python

    import unittest
    import calc   # the file you’re testing

    class TestCalc(unittest.TestCase):

        def test_add(self):
            self.assertEqual(calc.add(2, 3), 5)

        def test_subtract(self):
            self.assertEqual(calc.subtract(5, 3), 2)

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

**Common Assertions**

+--------------------------+--------------------------------+
| Method                   | Description                    |
+==========================+================================+
| ``assertEqual(a, b)``    | a == b                         |
+--------------------------+--------------------------------+
| ``assertNotEqual(a, b)`` | a != b                         |
+--------------------------+--------------------------------+
| ``assertTrue(x)``        | bool(x) is True                |
+--------------------------+--------------------------------+
| ``assertFalse(x)``       | bool(x) is False               |
+--------------------------+--------------------------------+
| ``assertIsNone(x)``      | x is None                      |
+--------------------------+--------------------------------+
| ``assertIn(a, b)``       | a in b                         |
+--------------------------+--------------------------------+
| ``assertRaises(Error)``  | checks for exceptions          |
+--------------------------+--------------------------------+

-------------------------------------
Using pytest (Popular Alternative)
-------------------------------------

**Simple Example**

.. code-block:: python

    def add(a, b):
        return a + b

    def test_add():
        assert add(2, 3) == 5

**Run tests**

.. code-block:: bash

    pytest

**Pytest Extras**

* ``pytest -v`` → verbose  
* ``pytest -q`` → quiet  
* ``pytest <file>`` → run specific file  
* ``pytest -k "add"`` → run tests with “add” in the name  
* ``pytest --maxfail=1 --disable-warnings -q`` → stop on first fail  

--------------------------
Best Practices
--------------------------

* One ``test_`` file per module.
* Each test function name starts with ``test_``.
* Keep tests independent.
* Use descriptive names (e.g. ``test_add_positive_numbers``).
* Automate with CI/CD (e.g., GitHub Actions).

--------------------------
Useful Tools
--------------------------

+--------------+----------------------------------------------+
| Tool         | Purpose                                      |
+==============+==============================================+
| ``unittest`` | Built-in, solid for small/medium projects    |
+--------------+----------------------------------------------+
| ``pytest``   | Simpler syntax, plugins, better reporting    |
+--------------+----------------------------------------------+
| ``nose2``    | Successor to nose (older, less used now)     |
+--------------+----------------------------------------------+
| ``coverage`` | Measures code coverage                       |
+--------------+----------------------------------------------+
| ``tox``      | Test across multiple environments            |
+--------------+----------------------------------------------+