michael@0: # This Source Code Form is subject to the terms of the Mozilla Public
michael@0: # License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0: # file, You can obtain one at http://mozilla.org/MPL/2.0/.
michael@0: 
michael@0: import sys
michael@0: import os
michael@0: from mozunit import main, MockedOpen
michael@0: import unittest
michael@0: from tempfile import mkstemp
michael@0: 
michael@0: class TestMozUnit(unittest.TestCase):
michael@0:     def test_mocked_open(self):
michael@0:         # Create a temporary file on the file system.
michael@0:         (fd, path) = mkstemp()
michael@0:         with os.fdopen(fd, 'w') as file:
michael@0:             file.write('foobar');
michael@0: 
michael@0:         self.assertFalse(os.path.exists('file1'))
michael@0:         self.assertFalse(os.path.exists('file2'))
michael@0: 
michael@0:         with MockedOpen({'file1': 'content1',
michael@0:                          'file2': 'content2'}):
michael@0:             self.assertTrue(os.path.exists('file1'))
michael@0:             self.assertTrue(os.path.exists('file2'))
michael@0:             self.assertFalse(os.path.exists('foo/file1'))
michael@0: 
michael@0:             # Check the contents of the files given at MockedOpen creation.
michael@0:             self.assertEqual(open('file1', 'r').read(), 'content1')
michael@0:             self.assertEqual(open('file2', 'r').read(), 'content2')
michael@0: 
michael@0:             # Check that overwriting these files alters their content.
michael@0:             with open('file1', 'w') as file:
michael@0:                 file.write('foo')
michael@0:             self.assertTrue(os.path.exists('file1'))
michael@0:             self.assertEqual(open('file1', 'r').read(), 'foo')
michael@0: 
michael@0:             # ... but not until the file is closed.
michael@0:             file = open('file2', 'w')
michael@0:             file.write('bar')
michael@0:             self.assertEqual(open('file2', 'r').read(), 'content2')
michael@0:             file.close()
michael@0:             self.assertEqual(open('file2', 'r').read(), 'bar')
michael@0: 
michael@0:             # Check that appending to a file does append
michael@0:             with open('file1', 'a') as file:
michael@0:                 file.write('bar')
michael@0:             self.assertEqual(open('file1', 'r').read(), 'foobar')
michael@0: 
michael@0:             self.assertFalse(os.path.exists('file3'))
michael@0: 
michael@0:             # Opening a non-existing file ought to fail.
michael@0:             self.assertRaises(IOError, open, 'file3', 'r')
michael@0:             self.assertFalse(os.path.exists('file3'))
michael@0: 
michael@0:             # Check that writing a new file does create the file.
michael@0:             with open('file3', 'w') as file:
michael@0:                 file.write('baz')
michael@0:             self.assertEqual(open('file3', 'r').read(), 'baz')
michael@0:             self.assertTrue(os.path.exists('file3'))
michael@0: 
michael@0:             # Check the content of the file created outside MockedOpen.
michael@0:             self.assertEqual(open(path, 'r').read(), 'foobar')
michael@0: 
michael@0:             # Check that overwriting a file existing on the file system
michael@0:             # does modify its content.
michael@0:             with open(path, 'w') as file:
michael@0:                 file.write('bazqux')
michael@0:             self.assertEqual(open(path, 'r').read(), 'bazqux')
michael@0: 
michael@0:         with MockedOpen():
michael@0:             # Check that appending to a file existing on the file system
michael@0:             # does modify its content.
michael@0:             with open(path, 'a') as file:
michael@0:                 file.write('bazqux')
michael@0:             self.assertEqual(open(path, 'r').read(), 'foobarbazqux')
michael@0: 
michael@0:         # Check that the file was not actually modified on the file system.
michael@0:         self.assertEqual(open(path, 'r').read(), 'foobar')
michael@0:         os.remove(path)
michael@0: 
michael@0:         # Check that the file created inside MockedOpen wasn't actually
michael@0:         # created.
michael@0:         self.assertRaises(IOError, open, 'file3', 'r')
michael@0: 
michael@0: if __name__ == "__main__":
michael@0:     main()