What is the unittest module in Python?

The unittest module is a built-in Python library that is used for testing the functionality of individual units of source code. It is a powerful tool that allows developers to write and run repeatable tests, which can help to ensure that their code is working as intended and that it remains reliable over time.

The unittest module provides several key features, including:

• The ability to define test cases and test suites, which can be used to group together related tests
• A set of assert methods that can be used to verify that code is behaving as expected
• Support for running tests in parallel, which can help to speed up the testing process

Before we dive into the specifics of the directory structure, it’s important to understand some key concepts related to unittest.

• Test Case: A test case is an individual unit of testing. It consists of a set of inputs and the expected output or behavior for those inputs. Test cases are written using the unittest module, and are typically stored in separate files from the main codebase.
• Test Suite: A test suite is a collection of test cases that are run together. Test suites allow you to group related test cases and run them as a single unit.
• Test Runner: A test runner is a tool that executes the test suite and displays the results. There are several test runners available for Python, including the built-in unittest runner and third-party tools such as pytest.

In this article, we will take a look at the typical directory structure for running tests using unittest in Python.