def test_parse_header(self, nr_segments, offsets):
"""Test parsing header data."""
# Encode the header
header = bytearray()
header.extend(pack('<L', nr_segments))
header.extend(pack('<{}L'.format(len(offsets)), *offsets))
# Add padding
header.extend(b'\x00' * (64 - len(header)))
assert len(header) == 64
assert offsets == _parse_rle_header(header)
def test_invalid_nr_segments_raises(self):
"""Test that more than 15 segments raises exception."""
with pytest.raises(ValueError, match="invalid number of segments"):
_parse_rle_header(b'\x10' + b'\x00' * 63)
def test_invalid_header_length(self):
"""Test exception raised if header is not 64 bytes long."""
for length in [0, 1, 63, 65]:
with pytest.raises(ValueError,
match='RLE header can only be 64 bytes long'):
_parse_rle_header(b'\x00' * length)