#! /usr/bin/env python

"""Basic tests for os.popen()



  Particularly useful for platforms that fake popen.

"""



import unittest

from test import test_support

import os, sys



# Test that command-lines get down as we expect.

# To do this we execute:

#    python -c "import sys;print sys.argv" {rest_of_commandline}

# This results in Python being spawned and printing the sys.argv list.

# We can then eval() the result of this, and see what each argv was.

python = sys.executable

if ' ' in python:

    python = '"' + python + '"'     # quote embedded space for cmdline



class PopenTest(unittest.TestCase):

    def _do_test_commandline(self, cmdline, expected):

        cmd = '%s -c "import sys;print sys.argv" %s' % (python, cmdline)

        data = os.popen(cmd).read()

        got = eval(data)[1:] # strip off argv[0]

        self.assertEqual(got, expected)



    def test_popen(self):

        self.assertRaises(TypeError, os.popen)

        self._do_test_commandline(

            "foo bar",

            ["foo", "bar"]

        )

        self._do_test_commandline(

            'foo "spam and eggs" "silly walk"',

            ["foo", "spam and eggs", "silly walk"]

        )

        self._do_test_commandline(

            'foo "a \\"quoted\\" arg" bar',

            ["foo", 'a "quoted" arg', "bar"]

        )

        test_support.reap_children()



def test_main():

    test_support.run_unittest(PopenTest)



if __name__ == "__main__":

    test_main()

