The pytest framework makes it easy to write small tests, yet scales to support complex functional testing for applications and libraries.

An example of a simple test:

# content of test_sample.py
def inc(x):
 return x + 1
def test_answer():
 assert inc(3) == 5

To execute it:

$ pytest
============================= test session starts =============================
collected 1 items
test_sample.py F
================================== FAILURES ===================================
_________________________________ test_answer _________________________________
 def test_answer():
> assert inc(3) == 5
E assert 4 == 5
E + where 4 = inc(3)
test_sample.py:5: AssertionError
========================== 1 failed in 0.04 seconds ===========================

Due to pytest's detailed assertion introspection, only plain assert statements are used. See getting-started for more examples.

• Detailed info on failing assert statements (no need to remember self.assert* names);
• Auto-discovery of test modules and functions;
• Modular fixtures for managing small or parametrized long-lived test resources;
• Can run unittest (or trial), nose test suites out of the box;
• Python 2.7, Python 3.4+, PyPy 2.3, Jython 2.5 (untested);
• Rich plugin architecture, with over 315+ external plugins and thriving community;

For full documentation, including installation, tutorials and PDF documents, please see http://docs.pytest.org.

Please use the GitHub issue tracker to submit bugs or request features.

Consult the Changelog page for fixes and enhancements of each version.

Copyright Holger Krekel and others, 2004-2017.

Distributed under the terms of the MIT license, pytest is free and open source software.