pytest-rerunfailures is a plugin for py.test that re-runs tests to eliminate intermittent failures.
You will need the following prerequisites in order to use pytest-rerunfailures:
- Python 2.6, 2.7, 3.3, 3.4, 3.5, PyPy, or PyPy3
- py.test 2.4.2 or newer, except Python 3.5 that needs py.test 2.7.3 or newer
To install pytest-rerunfailures:
$ pip install pytest-rerunfailures
Re-run all failures
To re-run all test failures, use the
--reruns command line option with the
maximum number of times you'd like the tests to run:
$ py.test --rerun 5
Re-run individual failures
To mark individual tests as flaky, and have them automatically re-run when they
fail, add the
flaky mark with the maximum number of times you'd like the
test to run:
@pytest.mark.flaky(reruns=5) def test_example(): import random assert random.choice([True, False])
Note that when teardown fails, two reports are generated for the case, one for the test case and the other for the teardown error.
Here's an example of the output provided by the plugin when run with
--reruns 2 and
test_report.py RRF ================================== FAILURES ================================== __________________________________ test_fail _________________________________ def test_fail(): > assert False E assert False test_report.py:9: AssertionError ============================ rerun test summary info ========================= RERUN test_report.py::test_fail RERUN test_report.py::test_fail ============================ short test summary info ========================= FAIL test_report.py::test_fail ======================= 1 failed, 2 rerun in 0.02 seconds ====================
Note that output will show all re-runs. Tests that fail on all the re-runs will be marked as failed. Due to a current limitation in pytest-xdist, when running tests in parallel only the final result will be included in the output.
- This plugin may not be used with class, module, and package level fixtures.
- This plugin is not compatible with pytest-xdist's --looponfail flag.
- This plugin is not compatible with the core --pdb flag.
- The support for Python 3.5 is limited to pytest 2.7.3 and higher. (Will break
TypeError: Call constructor takes either 0 or 3 positional argumentsfor older versions, see https://github.com/pytest-dev/pytest/issues/744)