1"""Basic tests for os.popen()
2
3  Particularly useful for platforms that fake popen.
4"""
5
6import unittest
7from test import support
8import os, sys
9
10# Test that command-lines get down as we expect.
11# To do this we execute:
12#    python -c "import sys;print(sys.argv)" {rest_of_commandline}
13# This results in Python being spawned and printing the sys.argv list.
14# We can then eval() the result of this, and see what each argv was.
15python = sys.executable
16if ' ' in python:
17    python = '"' + python + '"'     # quote embedded space for cmdline
18
19class PopenTest(unittest.TestCase):
20
21    def _do_test_commandline(self, cmdline, expected):
22        cmd = '%s -c "import sys; print(sys.argv)" %s'
23        cmd = cmd % (python, cmdline)
24        with os.popen(cmd) as p:
25            data = p.read()
26        got = eval(data)[1:] # strip off argv[0]
27        self.assertEqual(got, expected)
28
29    def test_popen(self):
30        self.assertRaises(TypeError, os.popen)
31        self._do_test_commandline(
32            "foo bar",
33            ["foo", "bar"]
34        )
35        self._do_test_commandline(
36            'foo "spam and eggs" "silly walk"',
37            ["foo", "spam and eggs", "silly walk"]
38        )
39        self._do_test_commandline(
40            'foo "a \\"quoted\\" arg" bar',
41            ["foo", 'a "quoted" arg', "bar"]
42        )
43        support.reap_children()
44
45    def test_return_code(self):
46        self.assertEqual(os.popen("exit 0").close(), None)
47        if os.name == 'nt':
48            self.assertEqual(os.popen("exit 42").close(), 42)
49        else:
50            self.assertEqual(os.popen("exit 42").close(), 42 << 8)
51
52    def test_contextmanager(self):
53        with os.popen("echo hello") as f:
54            self.assertEqual(f.read(), "hello\n")
55
56    def test_iterating(self):
57        with os.popen("echo hello") as f:
58            self.assertEqual(list(f), ["hello\n"])
59
60    def test_keywords(self):
61        with os.popen(cmd="exit 0", mode="w", buffering=-1):
62            pass
63
64if __name__ == "__main__":
65    unittest.main()
66