Lib/test/test_zlib.py

   1 import zlib
   2 import sys
   3 import imp
   4 import string
   5
   6 try:
   7     t = imp.find_module('test_zlib')
   8     file = t[0]
   9 except ImportError:
  10     file = open(__file__)
  11 buf = file.read() * 8
  12 file.close()
  13
  14 # test the chucksums (hex so the test doesn't break on 64-bit machines)
  15 print hex(zlib.crc32('penguin')), hex(zlib.crc32('penguin', 1))
  16 print hex(zlib.adler32('penguin')), hex(zlib.adler32('penguin', 1))
  17
  18 # make sure we generate some expected errors
  19 try:
  20     zlib.compress('ERROR', zlib.MAX_WBITS + 1)
  21 except zlib.error, msg:
  22     print "expecting", msg
  23 try:
  24     zlib.compressobj(1, 8, 0)
  25 except ValueError, msg:
  26     print "expecting", msg
  27 try:
  28     zlib.decompressobj(0)
  29 except ValueError, msg:
  30     print "expecting", msg
  31
  32 x = zlib.compress(buf)
  33 y = zlib.decompress(x)
  34 if buf != y:
  35     print "normal compression/decompression failed"
  36 else:
  37     print "normal compression/decompression succeeded"
  38
  39 buf = buf * 16
  40
  41 co = zlib.compressobj(8, 8, -15)
  42 x1 = co.compress(buf)
  43 x2 = co.flush()
  44 x = x1 + x2
  45
  46 dc = zlib.decompressobj(-15)
  47 y1 = dc.decompress(x)
  48 y2 = dc.flush()
  49 y = y1 + y2
  50 if buf != y:
  51     print "compress/decompression obj failed"
  52 else:
  53     print "compress/decompression obj succeeded"
  54
  55 co = zlib.compressobj(2, 8, -12, 9, 1)
  56 bufs = []
  57 for i in range(0, len(buf), 256):
  58     bufs.append(co.compress(buf[i:i+256]))
  59 bufs.append(co.flush())
  60 combuf = string.join(bufs, '')
  61
  62 decomp1 = zlib.decompress(combuf, -12, -5)
  63 if decomp1 != buf:
  64     print "decompress with init options failed"
  65 else:
  66     print "decompress with init options succeeded"
  67
  68 deco = zlib.decompressobj(-12)
  69 bufs = []
  70 for i in range(0, len(combuf), 128):
  71     bufs.append(deco.decompress(combuf[i:i+128]))
  72 bufs.append(deco.flush())
  73 decomp2 = string.join(buf, '')
  74 if decomp2 != buf:
  75     print "decompressobj with init options failed"
  76 else:
  77     print "decompressobj with init options succeeded"
  78
  79 def ignore():
  80     """An empty function with a big string.
  81
  82     Make the compression algorithm work a little harder.
  83     """
  84
  85     """
  86 LAERTES
  87
  88        O, fear me not.
  89        I stay too long: but here my father comes.
  90
  91        Enter POLONIUS
  92
  93        A double blessing is a double grace,
  94        Occasion smiles upon a second leave.
  95
  96 LORD POLONIUS
  97
  98        Yet here, Laertes! aboard, aboard, for shame!
  99        The wind sits in the shoulder of your sail,
 100        And you are stay'd for. There; my blessing with thee!
 101        And these few precepts in thy memory
 102        See thou character. Give thy thoughts no tongue,
 103        Nor any unproportioned thought his act.
 104        Be thou familiar, but by no means vulgar.
 105        Those friends thou hast, and their adoption tried,
 106        Grapple them to thy soul with hoops of steel;
 107        But do not dull thy palm with entertainment
 108        Of each new-hatch'd, unfledged comrade. Beware
 109        Of entrance to a quarrel, but being in,
 110        Bear't that the opposed may beware of thee.
 111        Give every man thy ear, but few thy voice;
 112        Take each man's censure, but reserve thy judgment.
 113        Costly thy habit as thy purse can buy,
 114        But not express'd in fancy; rich, not gaudy;
 115        For the apparel oft proclaims the man,
 116        And they in France of the best rank and station
 117        Are of a most select and generous chief in that.
 118        Neither a borrower nor a lender be;
 119        For loan oft loses both itself and friend,
 120        And borrowing dulls the edge of husbandry.
 121        This above all: to thine ownself be true,
 122        And it must follow, as the night the day,
 123        Thou canst not then be false to any man.
 124        Farewell: my blessing season this in thee!
 125
 126 LAERTES
 127
 128        Most humbly do I take my leave, my lord.
 129
 130 LORD POLONIUS
 131
 132        The time invites you; go; your servants tend.
 133
 134 LAERTES
 135
 136        Farewell, Ophelia; and remember well
 137        What I have said to you.
 138
 139 OPHELIA
 140
 141        'Tis in my memory lock'd,
 142        And you yourself shall keep the key of it.
 143
 144 LAERTES
 145
 146        Farewell.
 147 """
 148