import unittest
from test import support
from test.support import import_helper
import binascii
import copy
import pickle
import random
import sys
from test.support import bigmemtest, _1G, _4G, is_s390x
zlib = import_helper.import_module('zlib')
requires_Compress_copy = unittest.skipUnless(
hasattr(zlib.compressobj(), "copy"),
'requires Compress.copy()')
requires_Decompress_copy = unittest.skipUnless(
hasattr(zlib.decompressobj(), "copy"),
'requires Decompress.copy()')
def _zlib_runtime_version_tuple(zlib_version=zlib.ZLIB_RUNTIME_VERSION):
# Register "1.2.3" as "1.2.3.0"
# or "1.2.0-linux","1.2.0.f","1.2.0.f-linux"
v = zlib_version.split('-', 1)[0].split('.')
if len(v) < 4:
v.append('0')
elif not v[-1].isnumeric():
v[-1] = '0'
return tuple(map(int, v))
ZLIB_RUNTIME_VERSION_TUPLE = _zlib_runtime_version_tuple()
# bpo-46623: When a hardware accelerator is used (currently only on s390x),
# using different ways to compress data with zlib can produce different
# compressed data.
# Simplified test_pair() code:
#
# def func1(data):
# return zlib.compress(data)
#
# def func2(data)
# co = zlib.compressobj()
# x1 = co.compress(data)
# x2 = co.flush()
# return x1 + x2
#
# On s390x if zlib uses a hardware accelerator, func1() creates a single
# "final" compressed block whereas func2() produces 3 compressed blocks (the
# last one is a final block). On other platforms with no accelerator, func1()
# and func2() produce the same compressed data made of a single (final)
# compressed block.
#
# Only the compressed data is different, the decompression returns the original
# data:
#
# zlib.decompress(func1(data)) == zlib.decompress(func2(data)) == data
#
# To simplify the skip condition, make the assumption that s390x always has an
# accelerator, and nothing else has it.
HW_ACCELERATED = is_s390x
class VersionTestCase(unittest.TestCase):
def test_library_version(self):
# Test that the major version of the actual library in use matches the
# major version that we were compiled against. We can't guarantee that
# the minor versions will match (even on the machine on which the module
# was compiled), and the API is stable between minor versions, so
# testing only the major versions avoids spurious failures.
self.assertEqual(zlib.ZLIB_RUNTIME_VERSION[0], zlib.ZLIB_VERSION[0])
class ChecksumTestCase(unittest.TestCase):
# checksum test cases
def test_crc32start(self):
self.assertEqual(zlib.crc32(b""), zlib.crc32(b"", 0))
self.assertTrue(zlib.crc32(b"abc", 0xffffffff))
def test_crc32empty(self):
self.assertEqual(zlib.crc32(b"", 0), 0)
self.assertEqual(zlib.crc32(b"", 1), 1)
self.assertEqual(zlib.crc32(b"", 432), 432)
def test_adler32start(self):
self.assertEqual(zlib.adler32(b""), zlib.adler32(b"", 1))
self.assertTrue(zlib.adler32(b"abc", 0xffffffff))
def test_adler32empty(self):
self.assertEqual(zlib.adler32(b"", 0), 0)
self.assertEqual(zlib.adler32(b"", 1), 1)
self.assertEqual(zlib.adler32(b"", 432), 432)
def test_penguins(self):
self.assertEqual(zlib.crc32(b"penguin", 0), 0x0e5c1a120)
self.assertEqual(zlib.crc32(b"penguin", 1), 0x43b6aa94)
self.assertEqual(zlib.adler32(b"penguin", 0), 0x0bcf02f6)
self.assertEqual(zlib.adler32(b"penguin", 1), 0x0bd602f7)
self.assertEqual(zlib.crc32(b"penguin"), zlib.crc32(b"penguin", 0))
self.assertEqual(zlib.adler32(b"penguin"),zlib.adler32(b"penguin",1))
def test_crc32_adler32_unsigned(self):
foo = b'abcdefghijklmnop'
# explicitly test signed behavior
self.assertEqual(zlib.crc32(foo), 2486878355)
self.assertEqual(zlib.crc32(b'spam'), 1138425661)
self.assertEqual(zlib.adler32(foo+foo), 3573550353)
self.assertEqual(zlib.adler32(b'spam'), 72286642)
def test_same_as_binascii_crc32(self):
foo = b'abcdefghijklmnop'
crc = 2486878355
self.assertEqual(binascii.crc32(foo), crc)
self.assertEqual(zlib.crc32(foo), crc)
self.assertEqual(binascii.crc32(b'spam'), zlib.crc32(b'spam'))
# Issue #10276 - check that inputs >=4 GiB are handled correctly.
class ChecksumBigBufferTestCase(unittest.TestCase):
@bigmemtest(size=_4G + 4, memuse=1, dry_run=False)
def test_big_buffer(self, size):
data = b"nyan" * (_1G + 1)
self.assertEqual(zlib.crc32(data), 1044521549)
self.assertEqual(zlib.adler32(data), 2256789997)
class ExceptionTestCase(unittest.TestCase):
# make sure we generate some expected errors
def test_badlevel(self):
# specifying compression level out of range causes an error
# (but -1 is Z_DEFAULT_COMPRESSION and apparently the zlib
# accepts 0 too)
self.assertRaises(zlib.error, zlib.compress, b'ERROR', 10)
def test_badargs(self):
self.assertRaises(TypeError, zlib.adler32)
self.assertRaises(TypeError, zlib.crc32)
self.assertRaises(TypeError, zlib.compress)
self.assertRaises(TypeError, zlib.decompress)
for arg in (42, None, '', 'abc', (), []):
self.assertRaises(TypeError, zlib.adler32, arg)
self.assertRaises(TypeError, zlib.crc32, arg)
self.assertRaises(TypeError, zlib.compress, arg)
self.assertRaises(TypeError, zlib.decompress, arg)
def test_badcompressobj(self):
# verify failure on building compress object with bad params
self.assertRaises(ValueError, zlib.compressobj, 1, zlib.DEFLATED, 0)
# specifying total bits too large causes an error
self.assertRaises(ValueError,
zlib.compressobj, 1, zlib.DEFLATED, zlib.MAX_WBITS + 1)
def test_baddecompressobj(self):
# verify failure on building decompress object with bad params
self.assertRaises(ValueError, zlib.decompressobj, -1)
def test_decompressobj_badflush(self):
# verify failure on calling decompressobj.flush with bad params
self.assertRaises(ValueError, zlib.decompressobj().flush, 0)
self.assertRaises(ValueError, zlib.decompressobj().flush, -1)
@support.cpython_only
def test_overflow(self):
with self.assertRaisesRegex(OverflowError, 'int too large'):
zlib.decompress(b'', 15, sys.maxsize + 1)
with self.assertRaisesRegex(OverflowError, 'int too large'):
zlib.decompressobj().decompress(b'', sys.maxsize + 1)
with self.assertRaisesRegex(OverflowError, 'int too large'):
zlib.decompressobj().flush(sys.maxsize + 1)
@support.cpython_only
def test_disallow_instantiation(self):
# Ensure that the type disallows instantiation (bpo-43916)
support.check_disallow_instantiation(self, type(zlib.compressobj()))
support.check_disallow_instantiation(self, type(zlib.decompressobj()))
class BaseCompressTestCase(object):
def check_big_compress_buffer(self, size, compress_func):
_1M = 1024 * 1024
# Generate 10 MiB worth of random, and expand it by repeating it.
# The assumption is that zlib's memory is not big enough to exploit
# such spread out redundancy.
data = random.randbytes(_1M * 10)
data = data * (size // len(data) + 1)
try:
compress_func(data)
finally:
# Release memory
data = None
def check_big_decompress_buffer(self, size, decompress_func):
data = b'x' * size
try:
compressed = zlib.compress(data, 1)
finally:
# Release memory
data = None
data = decompress_func(compressed)
# Sanity check
try:
self.assertEqual(len(data), size)
self.assertEqual(len(data.strip(b'x')), 0)
finally:
data = None
class CompressTestCase(BaseCompressTestCase, unittest.TestCase):
# Test compression in one go (whole message compression)
def test_speech(self):
x = zlib.compress(HAMLET_SCENE)
self.assertEqual(zlib.decompress(x), HAMLET_SCENE)
def test_keywords(self):
x = zlib.compress(HAMLET_SCENE, level=3)
self.assertEqual(zlib.decompress(x), HAMLET_SCENE)
with self.assertRaises(TypeError):
zlib.compress(data=HAMLET_SCENE, level=3)
self.assertEqual(zlib.decompress(x,
wbits=zlib.MAX_WBITS,
bufsize=zlib.DEF_BUF_SIZE),
HAMLET_SCENE)
def test_speech128(self):
# compress more data
data = HAMLET_SCENE * 128
x = zlib.compress(data)
# With hardware acceleration, the compressed bytes
# might not be identical.
if not HW_ACCELERATED:
self.assertEqual(zlib.compress(bytearray(data)), x)
for ob in x, bytearray(x):
self.assertEqual(zlib.decompress(ob), data)
def test_incomplete_stream(self):
# A useful error message is given
x = zlib.compress(HAMLET_SCENE)
self.assertRaisesRegex(zlib.error,
"Error -5 while decompressing data: incomplete or truncated stream",
zlib.decompress, x[:-1])
# Memory use of the following functions takes into account overallocation
@bigmemtest(size=_1G + 1024 * 1024, memuse=3)
def test_big_compress_buffer(self, size):
compress = lambda s: zlib.compress(s, 1)
self.check_big_compress_buffer(size, compress)
@bigmemtest(size=_1G + 1024 * 1024, memuse=2)
def test_big_decompress_buffer(self, size):
self.check_big_decompress_buffer(size, zlib.decompress)
@bigmemtest(size=_4G, memuse=1)
def test_large_bufsize(self, size):
# Test decompress(bufsize) parameter greater than the internal limit
data = HAMLET_SCENE * 10
compressed = zlib.compress(data, 1)
self.assertEqual(zlib.decompress(compressed, 15, size), data)
def test_custom_bufsize(self):
data = HAMLET_SCENE * 10
compressed = zlib.compress(data, 1)
self.assertEqual(zlib.decompress(compressed, 15, CustomInt()), data)
@unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform')
@bigmemtest(size=_4G + 100, memuse=4)
def test_64bit_compress(self, size):
data = b'x' * size
try:
comp = zlib.compress(data, 0)
self.assertEqual(zlib.decompress(comp), data)
finally:
comp = data = None
class CompressObjectTestCase(BaseCompressTestCase, unittest.TestCase):
# Test compression object
def test_pair(self):
# straightforward compress/decompress objects
datasrc = HAMLET_SCENE * 128
datazip = zlib.compress(datasrc)
# should compress both bytes and bytearray data
for data in (datasrc, bytearray(datasrc)):
co = zlib.compressobj()
x1 = co.compress(data)
x2 = co.flush()
self.assertRaises(zlib.error, co.flush) # second flush should not work
# With hardware acceleration, the compressed bytes might not
# be identical.
if not HW_ACCELERATED:
self.assertEqual(x1 + x2, datazip)
for v1, v2 in ((x1, x2), (bytearray(x1), bytearray(x2))):
dco = zlib.decompressobj()
y1 = dco.decompress(v1 + v2)
y2 = dco.flush()
self.assertEqual(data, y1 + y2)
self.assertIsInstance(dco.unconsumed_tail, bytes)
self.assertIsInstance(dco.unused_data, bytes)
def test_keywords(self):
level = 2
method = zlib.DEFLATED
wbits = -12
memLevel = 9
strategy = zlib.Z_FILTERED
co = zlib.compressobj(level=level,
method=method,
wbits=wbits,
memLevel=memLevel,
strategy=strategy,
zdict=b"")
do = zlib.decompressobj(wbits=wbits, zdict=b"")
with self.assertRaises(TypeError):
co.compress(data=HAMLET_SCENE)
with self.assertRaises(TypeError):
do.decompress(data=zlib.compress(HAMLET_SCENE))
x = co.compress(HAMLET_SCENE) + co.flush()
y = do.decompress(x, max_length=len(HAMLET_SCENE)) + do.flush()
self.assertEqual(HAMLET_SCENE, y)
def test_compressoptions(self):
# specify lots of options to compressobj()
level = 2
method = zlib.DEFLATED
wbits = -12
memLevel = 9
strategy = zlib.Z_FILTERED
co = zlib.compressobj(level, method, wbits, memLevel, strategy)
x1 = co.compress(HAMLET_SCENE)
x2 = co.flush()
dco = zlib.decompressobj(wbits)
y1 = dco.decompress(x1 + x2)
y2 = dco.flush()
self.assertEqual(HAMLET_SCENE, y1 + y2)
def test_compressincremental(self):
# compress object in steps, decompress object as one-shot
data = HAMLET_SCENE * 128
co = zlib.compressobj()
bufs = []
for i in range(0, len(data), 256):
bufs.append(co.compress(data[i:i+256]))
bufs.append(co.flush())
combuf = b''.join(bufs)
dco = zlib.decompressobj()
y1 = dco.decompress(b''.join(bufs))
y2 = dco.flush()
self.assertEqual(data, y1 + y2)
def test_decompinc(self, flush=False, source=None, cx=256, dcx=64):
# compress object in steps, decompress object in steps
source = source or HAMLET_SCENE
data = source * 128
co = zlib.compressobj()
bufs = []
for i in range(0, len(data), cx):
bufs.append(co.compress(data[i:i+cx]))
bufs.append(co.flush())
combuf = b''.join(bufs)
decombuf = zlib.decompress(combuf)
# Test type of return value
self.assertIsInstance(decombuf, bytes)
self.assertEqual(data, decombuf)
dco = zlib.decompressobj()
bufs = []
for i in range(0, len(combuf), dcx):
bufs.append(dco.decompress(combuf[i:i+dcx]))
self.assertEqual(b'', dco.unconsumed_tail, ########
"(A) uct should be b'': not %d long" %
len(dco.unconsumed_tail))
self.assertEqual(b'', dco.unused_data)
if flush:
bufs.append(dco.flush())
else:
while True:
chunk = dco.decompress(b'')
if chunk:
bufs.append(chunk)
else:
break
self.assertEqual(b'', dco.unconsumed_tail, ########
"(B) uct should be b'': not %d long" %
len(dco.unconsumed_tail))
self.assertEqual(b'', dco.unused_data)
self.assertEqual(data, b''.join(bufs))
# Failure means: "decompressobj with init options failed"
def test_decompincflush(self):
self.test_decompinc(flush=True)
def test_decompimax(self, source=None, cx=256, dcx=64):
# compress in steps, decompress in length-restricted steps
source = source or HAMLET_SCENE
# Check a decompression object with max_length specified
data = source * 128
co = zlib.compressobj()
bufs = []
for i in range(0, len(data), cx):
bufs.append(co.compress(data[i:i+cx]))
bufs.append(co.flush())
combuf = b''.join(bufs)
self.assertEqual(data, zlib.decompress(combuf),
'compressed data failure')
dco = zlib.decompressobj()
bufs = []
cb = combuf
while cb:
#max_length = 1 + len(cb)//10
chunk = dco.decompress(cb, dcx)
self.assertFalse(len(chunk) > dcx,
'chunk too big (%d>%d)' % (len(chunk), dcx))
bufs.append(chunk)
cb = dco.unconsumed_tail
bufs.append(dco.flush())
self.assertEqual(data, b''.join(bufs), 'Wrong data retrieved')
def test_decompressmaxlen(self, flush=False):
# Check a decompression object with max_length specified
data = HAMLET_SCENE * 128
co = zlib.compressobj()
bufs = []
for i in range(0, len(data), 256):
bufs.append(co.compress(data[i:i+256]))
bufs.append(co.flush())
combuf = b''.join(bufs)
self.assertEqual(data, zlib.decompress(combuf),
'compressed data failure')
dco = zlib.decompressobj()
bufs = []
cb = combuf
while cb:
max_length = 1 + len(cb)//10
chunk = dco.decompress(cb, max_length)
self.assertFalse(len(chunk) > max_length,
'chunk too big (%d>%d)' % (len(chunk),max_length))
bufs.append(chunk)
cb = dco.unconsumed_tail
if flush:
bufs.append(dco.flush())
else:
while chunk:
chunk = dco.decompress(b'', max_length)
self.assertFalse(len(chunk) > max_length,
'chunk too big (%d>%d)' % (len(chunk),max_length))
bufs.append(chunk)
self.assertEqual(data, b''.join(bufs), 'Wrong data retrieved')
def test_decompressmaxlenflush(self):
self.test_decompressmaxlen(flush=True)
def test_maxlenmisc(self):
# Misc tests of max_length
dco = zlib.decompressobj()
self.assertRaises(ValueError, dco.decompress, b"", -1)
self.assertEqual(b'', dco.unconsumed_tail)
def test_maxlen_large(self):
# Sizes up to sys.maxsize should be accepted, although zlib is
# internally limited to expressing sizes with unsigned int
data = HAMLET_SCENE * 10
self.assertGreater(len(data), zlib.DEF_BUF_SIZE)
compressed = zlib.compress(data, 1)
dco = zlib.decompressobj()
self.assertEqual(dco.decompress(compressed, sys.maxsize), data)
def test_maxlen_custom(self):
data = HAMLET_SCENE * 10
compressed = zlib.compress(data, 1)
dco = zlib.decompressobj()
self.assertEqual(dco.decompress(compressed, CustomInt()), data[:100])
def test_clear_unconsumed_tail(self):
# Issue #12050: calling decompress() without providing max_length
# should clear the unconsumed_tail attribute.
cdata = b"x\x9cKLJ\x06\x00\x02M\x01" # "abc"
dco = zlib.decompressobj()
ddata = dco.decompress(cdata, 1)
ddata += dco.decompress(dco.unconsumed_tail)
self.assertEqual(dco.unconsumed_tail, b"")
def test_flushes(self):
# Test flush() with the various options, using all the
# different levels in order to provide more variations.
sync_opt = ['Z_NO_FLUSH', 'Z_SYNC_FLUSH', 'Z_FULL_FLUSH',
'Z_PARTIAL_FLUSH']
# Z_BLOCK has a known failure prior to 1.2.5.3
if ZLIB_RUNTIME_VERSION_TUPLE >= (1, 2, 5, 3):
sync_opt.append('Z_BLOCK')
sync_opt = [getattr(zlib, opt) for opt in sync_opt
if hasattr(zlib, opt)]
data = HAMLET_SCENE * 8
for sync in sync_opt:
for level in range(10):
with self.subTest(sync=sync, level=level):
obj = zlib.compressobj( level )
a = obj.compress( data[:3000] )
b = obj.flush( sync )
c = obj.compress( data[3000:] )
d = obj.flush()
self.assertEqual(zlib.decompress(b''.join([a,b,c,d])),
data, ("Decompress failed: flush "
"mode=%i, level=%i") % (sync, level))
del obj
@unittest.skipUnless(hasattr(zlib, 'Z_SYNC_FLUSH'),
'requires zlib.Z_SYNC_FLUSH')
def test_odd_flush(self):
# Test for odd flushing bugs noted in 2.0, and hopefully fixed in 2.1
import random
# Testing on 17K of "random" data
# Create compressor and decompressor objects
co = zlib.compressobj(zlib.Z_BEST_COMPRESSION)
dco = zlib.decompressobj()
# Try 17K of data
# generate random data stream
data = random.randbytes(17 * 1024)
# compress, sync-flush, and decompress
first = co.compress(data)
second = co.flush(zlib.Z_SYNC_FLUSH)
expanded = dco.decompress(first + second)
# if decompressed data is different from the input data, choke.
self.assertEqual(expanded, data, "17K random source doesn't match")
def test_empty_flush(self):
# Test that calling .flush() on unused objects works.
# (Bug #1083110 -- calling .flush() on decompress objects
# caused a core dump.)
co = zlib.compressobj(zlib.Z_BEST_COMPRESSION)
self.assertTrue(co.flush()) # Returns a zlib header
dco = zlib.decompressobj()
self.assertEqual(dco.flush(), b"") # Returns nothing
def test_dictionary(self):
h = HAMLET_SCENE
# Build a simulated dictionary out of the words in HAMLET.
words = h.split()
random.shuffle(words)
zdict = b''.join(words)
# Use it to compress HAMLET.
co = zlib.compressobj(zdict=zdict)
cd = co.compress(h) + co.flush()
# Verify that it will decompress with the dictionary.
dco = zlib.decompressobj(zdict=zdict)
self.assertEqual(dco.decompress(cd) + dco.flush(), h)
# Verify that it fails when not given the dictionary.
dco = zlib.decompressobj()
self.assertRaises(zlib.error, dco.decompress, cd)
def test_dictionary_streaming(self):
# This simulates the reuse of a compressor object for compressing
# several separate data streams.
co = zlib.compressobj(zdict=HAMLET_SCENE)
do = zlib.decompressobj(zdict=HAMLET_SCENE)
piece = HAMLET_SCENE[1000:1500]
d0 = co.compress(piece) + co.flush(zlib.Z_SYNC_FLUSH)
d1 = co.compress(piece[100:]) + co.flush(zlib.Z_SYNC_FLUSH)
d2 = co.compress(piece[:-100]) + co.flush(zlib.Z_SYNC_FLUSH)
self.assertEqual(do.decompress(d0), piece)
self.assertEqual(do.decompress(d1), piece[100:])
self.assertEqual(do.decompress(d2), piece[:-100])
def test_decompress_incomplete_stream(self):
# This is 'foo', deflated
x = b'x\x9cK\xcb\xcf\x07\x00\x02\x82\x01E'
# For the record
self.assertEqual(zlib.decompress(x), b'foo')
self.assertRaises(zlib.error, zlib.decompress, x[:-5])
# Omitting the stream end works with decompressor objects
# (see issue #8672).
dco = zlib.decompressobj()
y = dco.decompress(x[:-5])
y += dco.flush()
self.assertEqual(y, b'foo')
def test_decompress_eof(self):
x = b'x\x9cK\xcb\xcf\x07\x00\x02\x82\x01E' # 'foo'
dco = zlib.decompressobj()
self.assertFalse(dco.eof)
dco.decompress(x[:-5])
self.assertFalse(dco.eof)
dco.decompress(x[-5:])
self.assertTrue(dco.eof)
dco.flush()
self.assertTrue(dco.eof)
def test_decompress_eof_incomplete_stream(self):
x = b'x\x9cK\xcb\xcf\x07\x00\x02\x82\x01E' # 'foo'
dco = zlib.decompressobj()
self.assertFalse(dco.eof)
dco.decompress(x[:-5])
self.assertFalse(dco.eof)
dco.flush()
self.assertFalse(dco.eof)
def test_decompress_unused_data(self):
# Repeated calls to decompress() after EOF should accumulate data in
# dco.unused_data, instead of just storing the arg to the last call.
source = b'abcdefghijklmnopqrstuvwxyz'
remainder = b'0123456789'
y = zlib.compress(source)
x = y + remainder
for maxlen in 0, 1000:
for step in 1, 2, len(y), len(x):
dco = zlib.decompressobj()
data = b''
for i in range(0, len(x), step):
if i < len(y):
self.assertEqual(dco.unused_data, b'')
if maxlen == 0:
data += dco.decompress(x[i : i + step])
self.assertEqual(dco.unconsumed_tail, b'')
else:
data += dco.decompress(
dco.unconsumed_tail + x[i : i + step], maxlen)
data += dco.flush()
self.assertTrue(dco.eof)
self.assertEqual(data, source)
self.assertEqual(dco.unconsumed_tail, b'')
self.assertEqual(dco.unused_data, remainder)
# issue27164
def test_decompress_raw_with_dictionary(self):
zdict = b'abcdefghijklmnopqrstuvwxyz'
co = zlib.compressobj(wbits=-zlib.MAX_WBITS, zdict=zdict)
comp = co.compress(zdict) + co.flush()
dco = zlib.decompressobj(wbits=-zlib.MAX_WBITS, zdict=zdict)
uncomp = dco.decompress(comp) + dco.flush()
self.assertEqual(zdict, uncomp)
def test_flush_with_freed_input(self):
# Issue #16411: decompressor accesses input to last decompress() call
# in flush(), even if this object has been freed in the meanwhile.
input1 = b'abcdefghijklmnopqrstuvwxyz'
input2 = b'QWERTYUIOPASDFGHJKLZXCVBNM'
data = zlib.compress(input1)
dco = zlib.decompressobj()
dco.decompress(data, 1)
del data
data = zlib.compress(input2)
self.assertEqual(dco.flush(), input1[1:])
@bigmemtest(size=_4G, memuse=1)
def test_flush_large_length(self, size):
# Test flush(length) parameter greater than internal limit UINT_MAX
input = HAMLET_SCENE * 10
data = zlib.compress(input, 1)
dco = zlib.decompressobj()
dco.decompress(data, 1)
self.assertEqual(dco.flush(size), input[1:])
def test_flush_custom_length(self):
input = HAMLET_SCENE * 10
data = zlib.compress(input, 1)
dco = zlib.decompressobj()
dco.decompress(data, 1)
self.assertEqual(dco.flush(CustomInt()), input[1:])
@requires_Compress_copy
def test_compresscopy(self):
# Test copying a compression object
data0 = HAMLET_SCENE
data1 = bytes(str(HAMLET_SCENE, "ascii").swapcase(), "ascii")
for func in lambda c: c.copy(), copy.copy, copy.deepcopy:
c0 = zlib.compressobj(zlib.Z_BEST_COMPRESSION)
bufs0 = []
bufs0.append(c0.compress(data0))
c1 = func(c0)
bufs1 = bufs0[:]
bufs0.append(c0.compress(data0))
bufs0.append(c0.flush())
s0 = b''.join(bufs0)
bufs1.append(c1.compress(data1))
bufs1.append(c1.flush())
s1 = b''.join(bufs1)
self.assertEqual(zlib.decompress(s0),data0+data0)
self.assertEqual(zlib.decompress(s1),data0+data1)
@requires_Compress_copy
def test_badcompresscopy(self):
# Test copying a compression object in an inconsistent state
c = zlib.compressobj()
c.compress(HAMLET_SCENE)
c.flush()
self.assertRaises(ValueError, c.copy)
self.assertRaises(ValueError, copy.copy, c)
self.assertRaises(ValueError, copy.deepcopy, c)
@requires_Decompress_copy
def test_decompresscopy(self):
# Test copying a decompression object
data = HAMLET_SCENE
comp = zlib.compress(data)
# Test type of return value
self.assertIsInstance(comp, bytes)
for func in lambda c: c.copy(), copy.copy, copy.deepcopy:
d0 = zlib.decompressobj()
bufs0 = []
bufs0.append(d0.decompress(comp[:32]))
d1 = func(d0)
bufs1 = bufs0[:]
bufs0.append(d0.decompress(comp[32:]))
s0 = b''.join(bufs0)
bufs1.append(d1.decompress(comp[32:]))
s1 = b''.join(bufs1)
self.assertEqual(s0,s1)
self.assertEqual(s0,data)
@requires_Decompress_copy
def test_baddecompresscopy(self):
# Test copying a compression object in an inconsistent state
data = zlib.compress(HAMLET_SCENE)
d = zlib.decompressobj()
d.decompress(data)
d.flush()
self.assertRaises(ValueError, d.copy)
self.assertRaises(ValueError, copy.copy, d)
self.assertRaises(ValueError, copy.deepcopy, d)
def test_compresspickle(self):
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
with self.assertRaises((TypeError, pickle.PicklingError)):
pickle.dumps(zlib.compressobj(zlib.Z_BEST_COMPRESSION), proto)
def test_decompresspickle(self):
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
with self.assertRaises((TypeError, pickle.PicklingError)):
pickle.dumps(zlib.decompressobj(), proto)
# Memory use of the following functions takes into account overallocation
@bigmemtest(size=_1G + 1024 * 1024, memuse=3)
def test_big_compress_buffer(self, size):
c = zlib.compressobj(1)
compress = lambda s: c.compress(s) + c.flush()
self.check_big_compress_buffer(size, compress)
@bigmemtest(size=_1G + 1024 * 1024, memuse=2)
def test_big_decompress_buffer(self, size):
d = zlib.decompressobj()
decompress = lambda s: d.decompress(s) + d.flush()
self.check_big_decompress_buffer(size, decompress)
@unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform')
@bigmemtest(size=_4G + 100, memuse=4)
def test_64bit_compress(self, size):
data = b'x' * size
co = zlib.compressobj(0)
do = zlib.decompressobj()
try:
comp = co.compress(data) + co.flush()
uncomp = do.decompress(comp) + do.flush()
self.assertEqual(uncomp, data)
finally:
comp = uncomp = data = None
@unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform')
@bigmemtest(size=_4G + 100, memuse=3)
def test_large_unused_data(self, size):
data = b'abcdefghijklmnop'
unused = b'x' * size
comp = zlib.compress(data) + unused
do = zlib.decompressobj()
try:
uncomp = do.decompress(comp) + do.flush()
self.assertEqual(unused, do.unused_data)
self.assertEqual(uncomp, data)
finally:
unused = comp = do = None
@unittest.skipUnless(sys.maxsize > 2**32, 'requires 64bit platform')
@bigmemtest(size=_4G + 100, memuse=5)
def test_large_unconsumed_tail(self, size):
data = b'x' * size
do = zlib.decompressobj()
try:
comp = zlib.compress(data, 0)
uncomp = do.decompress(comp, 1) + do.flush()
self.assertEqual(uncomp, data)
self.assertEqual(do.unconsumed_tail, b'')
finally:
comp = uncomp = data = None
def test_wbits(self):
# wbits=0 only supported since zlib v1.2.3.5
supports_wbits_0 = ZLIB_RUNTIME_VERSION_TUPLE >= (1, 2, 3, 5)
co = zlib.compressobj(level=1, wbits=15)
zlib15 = co.compress(HAMLET_SCENE) + co.flush()
self.assertEqual(zlib.decompress(zlib15, 15), HAMLET_SCENE)
if supports_wbits_0:
self.assertEqual(zlib.decompress(zlib15, 0), HAMLET_SCENE)
self.assertEqual(zlib.decompress(zlib15, 32 + 15), HAMLET_SCENE)
with self.assertRaisesRegex(zlib.error, 'invalid window size'):
zlib.decompress(zlib15, 14)
dco = zlib.decompressobj(wbits=32 + 15)
self.assertEqual(dco.decompress(zlib15), HAMLET_SCENE)
dco = zlib.decompressobj(wbits=14)
with self.assertRaisesRegex(zlib.error, 'invalid window size'):
dco.decompress(zlib15)
co = zlib.compressobj(level=1, wbits=9)
zlib9 = co.compress(HAMLET_SCENE) + co.flush()
self.assertEqual(zlib.decompress(zlib9, 9), HAMLET_SCENE)
self.assertEqual(zlib.decompress(zlib9, 15), HAMLET_SCENE)
if supports_wbits_0:
self.assertEqual(zlib.decompress(zlib9, 0), HAMLET_SCENE)
self.assertEqual(zlib.decompress(zlib9, 32 + 9), HAMLET_SCENE)
dco = zlib.decompressobj(wbits=32 + 9)
self.assertEqual(dco.decompress(zlib9), HAMLET_SCENE)
co = zlib.compressobj(level=1, wbits=-15)
deflate15 = co.compress(HAMLET_SCENE) + co.flush()
self.assertEqual(zlib.decompress(deflate15, -15), HAMLET_SCENE)
dco = zlib.decompressobj(wbits=-15)
self.assertEqual(dco.decompress(deflate15), HAMLET_SCENE)
co = zlib.compressobj(level=1, wbits=-9)
deflate9 = co.compress(HAMLET_SCENE) + co.flush()
self.assertEqual(zlib.decompress(deflate9, -9), HAMLET_SCENE)
self.assertEqual(zlib.decompress(deflate9, -15), HAMLET_SCENE)
dco = zlib.decompressobj(wbits=-9)
self.assertEqual(dco.decompress(deflate9), HAMLET_SCENE)
co = zlib.compressobj(level=1, wbits=16 + 15)
gzip = co.compress(HAMLET_SCENE) + co.flush()
self.assertEqual(zlib.decompress(gzip, 16 + 15), HAMLET_SCENE)
self.assertEqual(zlib.decompress(gzip, 32 + 15), HAMLET_SCENE)
dco = zlib.decompressobj(32 + 15)
self.assertEqual(dco.decompress(gzip), HAMLET_SCENE)
for wbits in (-15, 15, 31):
with self.subTest(wbits=wbits):
expected = HAMLET_SCENE
actual = zlib.decompress(
zlib.compress(HAMLET_SCENE, wbits=wbits), wbits=wbits
)
self.assertEqual(expected, actual)
def choose_lines(source, number, seed=None, generator=random):
"""Return a list of number lines randomly chosen from the source"""
if seed is not None:
generator.seed(seed)
sources = source.split('\n')
return [generator.choice(sources) for n in range(number)]
HAMLET_SCENE = b"""
LAERTES
O, fear me not.
I stay too long: but here my father comes.
Enter POLONIUS
A double blessing is a double grace,
Occasion smiles upon a second leave.
LORD POLONIUS
Yet here, Laertes! aboard, aboard, for shame!
The wind sits in the shoulder of your sail,
And you are stay'd for. There; my blessing with thee!
And these few precepts in thy memory
See thou character. Give thy thoughts no tongue,
Nor any unproportioned thought his act.
Be thou familiar, but by no means vulgar.
Those friends thou hast, and their adoption tried,
Grapple them to thy soul with hoops of steel;
But do not dull thy palm with entertainment
Of each new-hatch'd, unfledged comrade. Beware
Of entrance to a quarrel, but being in,
Bear't that the opposed may beware of thee.
Give every man thy ear, but few thy voice;
Take each man's censure, but reserve thy judgment.
Costly thy habit as thy purse can buy,
But not express'd in fancy; rich, not gaudy;
For the apparel oft proclaims the man,
And they in France of the best rank and station
Are of a most select and generous chief in that.
Neither a borrower nor a lender be;
For loan oft loses both itself and friend,
And borrowing dulls the edge of husbandry.
This above all: to thine ownself be true,
And it must follow, as the night the day,
Thou canst not then be false to any man.
Farewell: my blessing season this in thee!
LAERTES
Most humbly do I take my leave, my lord.
LORD POLONIUS
The time invites you; go; your servants tend.
LAERTES
Farewell, Ophelia; and remember well
What I have said to you.
OPHELIA
'Tis in my memory lock'd,
And you yourself shall keep the key of it.
LAERTES
Farewell.
"""
class ZlibDecompressorTest(unittest.TestCase):
# Test adopted from test_bz2.py
TEXT = HAMLET_SCENE
DATA = zlib.compress(HAMLET_SCENE)
BAD_DATA = b"Not a valid deflate block"
BIG_TEXT = DATA * ((128 * 1024 // len(DATA)) + 1)
BIG_DATA = zlib.compress(BIG_TEXT)
def test_Constructor(self):
self.assertRaises(TypeError, zlib._ZlibDecompressor, "ASDA")
self.assertRaises(TypeError, zlib._ZlibDecompressor, -15, "notbytes")
self.assertRaises(TypeError, zlib._ZlibDecompressor, -15, b"bytes", 5)
def testDecompress(self):
zlibd = zlib._ZlibDecompressor()
self.assertRaises(TypeError, zlibd.decompress)
text = zlibd.decompress(self.DATA)
self.assertEqual(text, self.TEXT)
def testDecompressChunks10(self):
zlibd = zlib._ZlibDecompressor()
text = b''
n = 0
while True:
str = self.DATA[n*10:(n+1)*10]
if not str:
break
text += zlibd.decompress(str)
n += 1
self.assertEqual(text, self.TEXT)
def testDecompressUnusedData(self):
zlibd = zlib._ZlibDecompressor()
unused_data = b"this is unused data"
text = zlibd.decompress(self.DATA+unused_data)
self.assertEqual(text, self.TEXT)
self.assertEqual(zlibd.unused_data, unused_data)
def testEOFError(self):
zlibd = zlib._ZlibDecompressor()
text = zlibd.decompress(self.DATA)
self.assertRaises(EOFError, zlibd.decompress, b"anything")
self.assertRaises(EOFError, zlibd.decompress, b"")
@support.skip_if_pgo_task
@bigmemtest(size=_4G + 100, memuse=3.3)
def testDecompress4G(self, size):
# "Test zlib._ZlibDecompressor.decompress() with >4GiB input"
blocksize = min(10 * 1024 * 1024, size)
block = random.randbytes(blocksize)
try:
data = block * ((size-1) // blocksize + 1)
compressed = zlib.compress(data)
zlibd = zlib._ZlibDecompressor()
decompressed = zlibd.decompress(compressed)
self.assertTrue(decompressed == data)
finally:
data = None
compressed = None
decompressed = None
def testPickle(self):
for proto in range(pickle.HIGHEST_PROTOCOL + 1):
with self.assertRaises(TypeError):
pickle.dumps(zlib._ZlibDecompressor(), proto)
def testDecompressorChunksMaxsize(self):
zlibd = zlib._ZlibDecompressor()
max_length = 100
out = []
# Feed some input
len_ = len(self.BIG_DATA) - 64
out.append(zlibd.decompress(self.BIG_DATA[:len_],
max_length=max_length))
self.assertFalse(zlibd.needs_input)
self.assertEqual(len(out[-1]), max_length)
# Retrieve more data without providing more input
out.append(zlibd.decompress(b'', max_length=max_length))
self.assertFalse(zlibd.needs_input)
self.assertEqual(len(out[-1]), max_length)
# Retrieve more data while providing more input
out.append(zlibd.decompress(self.BIG_DATA[len_:],
max_length=max_length))
self.assertLessEqual(len(out[-1]), max_length)
# Retrieve remaining uncompressed data
while not zlibd.eof:
out.append(zlibd.decompress(b'', max_length=max_length))
self.assertLessEqual(len(out[-1]), max_length)
out = b"".join(out)
self.assertEqual(out, self.BIG_TEXT)
self.assertEqual(zlibd.unused_data, b"")
def test_decompressor_inputbuf_1(self):
# Test reusing input buffer after moving existing
# contents to beginning
zlibd = zlib._ZlibDecompressor()
out = []
# Create input buffer and fill it
self.assertEqual(zlibd.decompress(self.DATA[:100],
max_length=0), b'')
# Retrieve some results, freeing capacity at beginning
# of input buffer
out.append(zlibd.decompress(b'', 2))
# Add more data that fits into input buffer after
# moving existing data to beginning
out.append(zlibd.decompress(self.DATA[100:105], 15))
# Decompress rest of data
out.append(zlibd.decompress(self.DATA[105:]))
self.assertEqual(b''.join(out), self.TEXT)
def test_decompressor_inputbuf_2(self):
# Test reusing input buffer by appending data at the
# end right away
zlibd = zlib._ZlibDecompressor()
out = []
# Create input buffer and empty it
self.assertEqual(zlibd.decompress(self.DATA[:200],
max_length=0), b'')
out.append(zlibd.decompress(b''))
# Fill buffer with new data
out.append(zlibd.decompress(self.DATA[200:280], 2))
# Append some more data, not enough to require resize
out.append(zlibd.decompress(self.DATA[280:300], 2))
# Decompress rest of data
out.append(zlibd.decompress(self.DATA[300:]))
self.assertEqual(b''.join(out), self.TEXT)
def test_decompressor_inputbuf_3(self):
# Test reusing input buffer after extending it
zlibd = zlib._ZlibDecompressor()
out = []
# Create almost full input buffer
out.append(zlibd.decompress(self.DATA[:200], 5))
# Add even more data to it, requiring resize
out.append(zlibd.decompress(self.DATA[200:300], 5))
# Decompress rest of data
out.append(zlibd.decompress(self.DATA[300:]))
self.assertEqual(b''.join(out), self.TEXT)
def test_failure(self):
zlibd = zlib._ZlibDecompressor()
self.assertRaises(Exception, zlibd.decompress, self.BAD_DATA * 30)
# Previously, a second call could crash due to internal inconsistency
self.assertRaises(Exception, zlibd.decompress, self.BAD_DATA * 30)
@support.refcount_test
def test_refleaks_in___init__(self):
gettotalrefcount = support.get_attribute(sys, 'gettotalrefcount')
zlibd = zlib._ZlibDecompressor()
refs_before = gettotalrefcount()
for i in range(100):
zlibd.__init__()
self.assertAlmostEqual(gettotalrefcount() - refs_before, 0, delta=10)
class CustomInt:
def __index__(self):
return 100
if __name__ == "__main__":
unittest.main()
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