Python CLI program unit testing

Question

I am working on a python Command-Line-Interface program, and I find it boring when doing testings, for example, here is the help information of the program:

Answer 1

Maybe too little too late, but you can always use

import os.system
result =  os.system(<'Insert your command with options here'>
assert(0 == result)

In that way, you can run your program as if it was from command line, and evaluate the exit code.

(Update after I studied pytest) You can also use capsys. (from running pytest --fixtures)

capsys Enable text capturing of writes to sys.stdout and sys.stderr.

The captured output is made available via ``capsys.readouterr()`` method
calls, which return a ``(out, err)`` namedtuple.
``out`` and ``err`` will be ``text`` objects.