PyCharm can discover, run and debug unittest and pytest tests using the configured project interpreter.
Understanding the Concept
PyCharm can discover, run and debug unittest and pytest tests using the configured project interpreter. Select the framework in settings if automatic detection does not match the project.
Use the context menu Run or Debug action in the project editor.
How this fits into a real test suite
A reliable test starts with a specific expected behavior. Keep the fixture small, arrange the input, call the real code, and assert a result the reader can verify. Add one boundary or failure case so the test does not pass only for a convenient example. In a larger project, run the same test automatically after each change.
Tests are repeatable experiments. Use temporary resources and injected dependencies where possible; when the environment is part of the requirement, add a separate integration test rather than weakening the unit test.
Worked Example
Read the code from the first line to the last. Identify which values are inputs, which operation is being demonstrated and what should happen before running it.
import unittest
class PyCharmExampleTests(unittest.TestCase):
def test_upper(self):
self.assertEqual('ready'.upper(), 'READY')Walkthrough: What Each Part Does
- The imports make unittest available. These are standard-library building blocks unless the example explicitly names an external tool.
- The definition PyCharmExampleTests creates reusable behavior. Its body runs when called, awaited or instantiated; defining it alone does not run the body of an ordinary function.
- The final check compares actual behavior with an explicit expectation. A successful test tells you that this particular case passed, not that every possible input works.
This demonstration focuses on one practical behavior. Before changing several lines, vary one input or one configuration choice and check whether the result changes for the reason you expected.
The example uses terminal, platform, external tool or process behavior that was not exercised automatically. Run it only in a suitable environment after reviewing the shown permissions and paths.
Important Behavior and Edge Cases
Using the wrong interpreter and concluding that a test or dependency is missing from the project.
Use the context menu Run or Debug action in the project editor.
Practice Exercise
Right-click a TestCase file in PyCharm and run it, then set a breakpoint in the tested function.
Write down the result you expect before running your changed code. Check at least one normal case and one boundary or failure case. If your example starts workers or opens resources, verify how they are cleaned up.
Further reading: official documentation and API reference.
Common Beginner Mistakes
- Using the wrong interpreter and concluding that a test or dependency is missing from the project.
- Writing assertions that check implementation details but fail to validate the behavior that matters to the caller.
Key Takeaways
- PyCharm can discover, run and debug unittest and pytest tests using the configured project interpreter.
- Use the context menu Run or Debug action in the project editor.
- Practice: Right-click a TestCase file in PyCharm and run it, then set a breakpoint in the tested function.