pytest: helps you write better programs¶
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 ============================
platform linux -- Python 3.x.y, pytest-3.x.y, py-1.x.y, pluggy-0.x.y
rootdir: $REGENDOC_TMPDIR, inifile:
collected 1 item
test_sample.py F [100%]
================================= FAILURES =================================
_______________________________ test_answer ________________________________
def test_answer():
> assert inc(3) == 5
E assert 4 == 5
E + where 4 = inc(3)
test_sample.py:6: AssertionError
========================= 1 failed in 0.12 seconds =========================
Due to pytest’s detailed assertion introspection, only plain assert statements are used.
See Getting Started for more examples.
Features¶
- 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 (including trial) and 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;