Summary  
This chapter covers how to discover and execute Python tests using the built-in unittest module, including running all tests or targeting specific test files and interpreting test result outputs (dots for passes, F for failures, E for errors).

General domain of usage  
Automated software testing

Running Python tests is usually done from the command line, giving you quick feedback on the state of your code. The built-in `unittest` module lets you easily discover and run tests directly from the terminal.

```
# To run all tests in the current directory and its subdirectories using unittest:
python -m unittest discover
```

When you run tests, Python shows the results in the terminal. A dot (`.`) means a test passed, **F** indicates a failure, and **E** indicates an error. At the end, you’ll see a summary with the total number of tests and details about any issues.

To run a specific test file, provide its path and filename. This is helpful when you want to focus on a particular module or test set.


```
# To run a single test file named test_math.py:
python -m unittest test_math.py
```

Integrating test runs into your daily workflow is essential. You can automate test execution with scripts or continuous integration tools to ensure that your code remains reliable as it evolves.

Note

How can you run all tests in a directory using unittest?

Learn how to write reliable Python code by testing it the right way. This short course introduces unit testing using Python’s built-in unittest framework, focusing on practical skills rather than theory. You’ll learn what unit tests are, why they matter, and how to write clear, meaningful tests for real Python functions. The course covers assertions, testing edge cases, handling exceptions, and understanding test failures. You’ll also learn how to structure test files and run tests confidently.

Get started with the basics of unit testing in Python. Learn what unit tests are, why they are important, and how they fit into the software development process.

Learn how to write clear and meaningful unit tests using assertions and by testing a variety of scenarios.

Discover how to test code that raises exceptions and how to interpret test failures.

Learn how to structure your test files and run tests efficiently.

Running Tests Confidently