'Check that calling read(0) on a ZipExtFile object returns an empty
string and doesn\'t advance file pointer.'

def test_read0(self):

    with zipfile.ZipFile(TESTFN, mode='w') as zipf:
        zipf.writestr('foo.txt', 'O,    for    a    Muse    of    Fire!')
        with zipf.open('foo.txt') as f:
            for i in range(FIXEDTEST_SIZE):
                self.assertEqual(f.read(0), '')
            self.assertEqual(f.read(), 'O,    for    a    Muse    of    Fire!')
