def test_fileno(tmp_path: Path) -> None:
file_path = tmp_path / "file"
file_path.write_bytes(b"abcd")
with file_path.open("rb") as fin:
obj = IOProxy(fin, 1, 3)
assert obj.fileno() == fin.fileno()
def test_seek() -> None:
original = Mock()
proxy = IOProxy(original, 4, 14)
assert proxy.tell() == 0
assert proxy.seek(7) == 7
assert proxy.tell() == 7
assert not original.method_calls # did not touch original
def parse(
cls,
fileobj: BinaryIO,
block_read_strategy: Optional[_BlockReadStrategyType] = None,
) -> "XZStream":
"""Parse one XZ stream from a fileobj.
fileobj position should be right at the end of the stream when calling
and will be moved right at the start of the stream
"""
# footer
footer_end_pos = fileobj.seek(-12, SEEK_CUR) + 12
footer = fileobj.read(12)
check, backward_size = parse_xz_footer(footer)
# index
block_start = fileobj.seek(-12 - backward_size, SEEK_CUR)
index = fileobj.read(backward_size)
records = parse_xz_index(index)
blocks_len = sum(
round_up(unpadded_size) for unpadded_size, _ in records)
block_start -= blocks_len
blocks = []
for unpadded_size, uncompressed_size in records:
block_end = block_start + round_up(unpadded_size)
blocks.append(
XZBlock(
IOProxy(fileobj, block_start, block_end),
check,
unpadded_size,
uncompressed_size,
block_read_strategy=block_read_strategy,
))
block_start = block_end
# header
fileobj.seek(-12 - blocks_len - backward_size, SEEK_CUR)
header = fileobj.read(12)
header_check = parse_xz_header(header)
if header_check != check:
raise XZError("stream: inconsistent check value")
header_start_pos = fileobj.seek(-12, SEEK_CUR)
stream_fileobj = IOProxy(fileobj, header_start_pos, footer_end_pos)
stream = cls(stream_fileobj,
check,
block_read_strategy=block_read_strategy)
for block in blocks:
stream._append(block)
return stream
def test_read() -> None:
originals: List[IOAbstract] = [
IOProxy(BytesIO(b"abc"), 0, 3),
generate_mock(0), # size 0, will be never used
IOProxy(BytesIO(b"defghij"), 0, 7),
]
combiner = IOCombiner(*originals)
# read all
originals[0].seek(2)
originals[2].seek(4)
combiner.seek(0)
assert combiner.read() == b"abcdefghij"
assert originals[0].tell() == 3
assert originals[2].tell() == 7
combiner.seek(4)
assert combiner.read() == b"efghij"
assert originals[0].tell() == 3
assert originals[2].tell() == 7
# read partial
originals[0].seek(2)
originals[2].seek(4)
combiner.seek(1)
assert combiner.read(6) == b"bcdefg"
assert originals[0].tell() == 3
assert originals[2].tell() == 4
assert combiner.read(6) == b"hij"
assert originals[0].tell() == 3
assert originals[2].tell() == 7
assert combiner.read(6) == b""
assert originals[0].tell() == 3
assert originals[2].tell() == 7
assert combiner.read(6) == b""
assert originals[0].tell() == 3
assert originals[2].tell() == 7
# with original seek
combiner.seek(1)
originals[0].seek(2)
originals[2].seek(4)
assert combiner.read(5) == b"bcdef"
assert originals[0].tell() == 3
assert originals[2].tell() == 3
# never used at all
assert not cast(Mock, originals[1]).method_calls
def test_truncate() -> None:
original = Mock()
with IOProxy(original, 4, 14) as proxy:
assert proxy.truncate(5) == 5
assert original.method_calls == [call.truncate(9)]
original.reset_mock()
assert proxy.truncate(20) == 20
assert original.method_calls == [call.truncate(24)]
def test_append() -> None:
combiner = IOCombiner[IOAbstract](generate_mock(13), generate_mock(37))
assert len(combiner) == 50
combiner._append( # pylint: disable=protected-access
IOProxy(BytesIO(b"abcdefghij"), 0, 10)
)
assert len(combiner) == 60
combiner.seek(54)
assert combiner.read(4) == b"efgh"
def test_write() -> None:
original = BytesIO(b"xxxxabcdefghijyyyyy")
with IOProxy(original, 4, 14) as proxy:
proxy.seek(10)
assert proxy.write(b"uvw") == 3
assert original.getvalue() == b"xxxxabcdefghijuvwyy"
assert proxy.write(b"UVWXYZ") == 6
assert original.getvalue() == b"xxxxabcdefghijuvwUVWXYZ"
def _create_fileobj(self) -> XZBlock:
self.fileobj.truncate(self._fileobj_blocks_end_pos)
return XZBlock(
IOProxy(
self.fileobj,
self._fileobj_blocks_end_pos,
self._fileobj_blocks_end_pos,
),
self.check,
0,
0,
self.preset,
self.filters,
self.block_read_strategy,
)
def test_read() -> None:
original = BytesIO(b"xxxxabcdefghijyyyyy")
proxy = IOProxy(original, 4, 14)
# read all
original.seek(2)
proxy.seek(0)
assert proxy.read() == b"abcdefghij"
assert original.tell() == 14
proxy.seek(4)
assert proxy.read() == b"efghij"
assert original.tell() == 14
# read partial
original.seek(2)
proxy.seek(6)
assert proxy.read(3) == b"ghi"
assert original.tell() == 13
assert proxy.read(3) == b"j"
assert original.tell() == 14
assert proxy.read(3) == b""
assert original.tell() == 14
assert proxy.read(3) == b""
assert original.tell() == 14
# with original seek
original.seek(2)
proxy.seek(4)
original.seek(1)
assert proxy.read() == b"efghij"
assert original.tell() == 14