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# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
import os
import unittest
from tempfile import mkstemp
from mozunit import MockedOpen, main
class TestMozUnit(unittest.TestCase):
def test_mocked_open(self):
# Create a temporary file on the file system.
(fd, path) = mkstemp()
with os.fdopen(fd, "w") as file:
file.write("foobar")
self.assertFalse(os.path.exists("file1"))
self.assertFalse(os.path.exists("file2"))
with MockedOpen({"file1": "content1", "file2": "content2"}):
self.assertTrue(os.path.exists("file1"))
self.assertTrue(os.path.exists("file2"))
self.assertFalse(os.path.exists("foo/file1"))
# Check the contents of the files given at MockedOpen creation.
self.assertEqual(open("file1", "r").read(), "content1")
self.assertEqual(open("file2", "r").read(), "content2")
# Check that overwriting these files alters their content.
with open("file1", "w") as file:
file.write("foo")
self.assertTrue(os.path.exists("file1"))
self.assertEqual(open("file1", "r").read(), "foo")
# ... but not until the file is closed.
file = open("file2", "w")
file.write("bar")
self.assertEqual(open("file2", "r").read(), "content2")
file.close()
self.assertEqual(open("file2", "r").read(), "bar")
# Check that appending to a file does append
with open("file1", "a") as file:
file.write("bar")
self.assertEqual(open("file1", "r").read(), "foobar")
self.assertFalse(os.path.exists("file3"))
# Opening a non-existing file ought to fail.
self.assertRaises(IOError, open, "file3", "r")
self.assertFalse(os.path.exists("file3"))
# Check that writing a new file does create the file.
with open("file3", "w") as file:
file.write("baz")
self.assertEqual(open("file3", "r").read(), "baz")
self.assertTrue(os.path.exists("file3"))
# Check the content of the file created outside MockedOpen.
self.assertEqual(open(path, "r").read(), "foobar")
# Check that overwriting a file existing on the file system
# does modify its content.
with open(path, "w") as file:
file.write("bazqux")
self.assertEqual(open(path, "r").read(), "bazqux")
with MockedOpen():
# Check that appending to a file existing on the file system
# does modify its content.
with open(path, "a") as file:
file.write("bazqux")
self.assertEqual(open(path, "r").read(), "foobarbazqux")
# Check that the file was not actually modified on the file system.
self.assertEqual(open(path, "r").read(), "foobar")
os.remove(path)
# Check that the file created inside MockedOpen wasn't actually
# created.
self.assertRaises(IOError, open, "file3", "r")
if __name__ == "__main__":
main()