tests: check returncode from executing external commands If a command fails, it could lead to undefined behavior, which lets tests fail without clear indication of the cause of the failures. Therefore, if not stated otherwise, check the return code.

babel >= 0.9.6, < 2.4
waitress >= 0.8.8, < 1.0
pytest ~= 3.0
pytest-runner
pytest-sugar>=0.7.0
pytest-catchlog
mock
sphinx
webtest < 3