'A zipfile entry with the wrong magic number should raise BadZipfile for
readfile(), but that should not affect other files in the archive.'

def test_invalidHeader(self):

    fn = self.makeZipFile(['test    contents', 'more    contents'])
    with zipfile.ZipFile(fn, 'r') as zf:
        zeroOffset = zf.getinfo('0').header_offset
    with open(fn, 'r+b') as scribble:
        scribble.seek(zeroOffset, 0)
        scribble.write(('0' * 4))
    with zipstream.ChunkingZipFile(fn) as czf:
        self.assertRaises(zipfile.BadZipfile, czf.readfile, '0')
        with czf.readfile('1') as zfe:
            self.assertEqual(zfe.read(), 'more    contents')
