def test_tell(self):
raw = RawDirect(self.file)
raw.write('A' * 512)
self.assertEquals(raw.tell(), 512)
raw.write('B' * 512)
self.assertEquals(raw.tell(), 1024)
raw.seek(0)
self.assertEquals(raw.read(512), ('A' * 512))
self.assertEquals(raw.read(512), ('B' * 512))
self.assertEquals(raw.tell(), 1024)
def test_write_past_device_eof(self):
# Create a sparse file that is less than the block size
fd, file = tempfile.mkstemp(dir='/tmp')
os.ftruncate(fd, 511)
os.close(fd)
try:
# Mount the file as a loopback device (simulate a block device)
device = find_loopback_device()
call("losetup %s %s" % (device, file), shell=True)
raw = RawDirect(device)
# Should raise IOError: [Errno 28] No space left on device
self.assertRaises(OSError, raw.write, 'A' * 512)
self.assertEquals(raw.tell(), 0)
self.assertEquals(os.lseek(raw._fd, 0, os.SEEK_CUR), 0)
raw.close()
finally:
call("losetup -d %s" % device, shell=True)
