Lib/test/test_gzip.py

   1 from test_support import verify
   2 import sys, os
   3 import gzip, tempfile
   4
   5 filename = tempfile.mktemp()
   6
   7 data1 = """  int length=DEFAULTALLOC, err = Z_OK;
   8   PyObject *RetVal;
   9   int flushmode = Z_FINISH;
  10   unsigned long start_total_out;
  11
  12 """
  13
  14 data2 = """/* zlibmodule.c -- gzip-compatible data compression */
  15 /* See http://www.cdrom.com/pub/infozip/zlib/ */
  16 /* See http://www.winimage.com/zLibDll for Windows */
  17 """
  18
  19 f = gzip.GzipFile(filename, 'wb') ; f.write(data1 * 50) ; f.close()
  20
  21 f = gzip.GzipFile(filename, 'r') ; d = f.read() ; f.close()
  22 verify(d == data1*50)
  23
  24 # Append to the previous file
  25 f = gzip.GzipFile(filename, 'ab') ; f.write(data2 * 15) ; f.close()
  26
  27 f = gzip.GzipFile(filename, 'rb') ; d = f.read() ; f.close()
  28 verify(d == (data1*50) + (data2*15))
  29
  30 # Try .readline() with varying line lengths
  31
  32 f = gzip.GzipFile(filename, 'rb')
  33 line_length = 0
  34 while 1:
  35     L = f.readline(line_length)
  36     if L == "" and line_length != 0: break
  37     verify(len(L) <= line_length)
  38     line_length = (line_length + 1) % 50
  39 f.close()
  40
  41 # Try .readlines()
  42
  43 f = gzip.GzipFile(filename, 'rb')
  44 L = f.readlines()
  45 f.close()
  46
  47 f = gzip.GzipFile(filename, 'rb')
  48 while 1:
  49     L = f.readlines(150)
  50     if L == []: break
  51 f.close()
  52
  53 # Try seek, read test
  54
  55 f = gzip.GzipFile(filename)
  56 while 1:
  57     oldpos = f.tell()
  58     line1 = f.readline()
  59     if not line1: break
  60     newpos = f.tell()
  61     f.seek(oldpos)  # negative seek
  62     if len(line1)>10:
  63         amount = 10
  64     else:
  65         amount = len(line1)
  66     line2 = f.read(amount)
  67     verify(line1[:amount] == line2)
  68     f.seek(newpos)  # positive seek
  69 f.close()
  70
  71 # Try seek, write test
  72 f = gzip.GzipFile(filename, 'w')
  73 for pos in range(0, 256, 16):
  74     f.seek(pos)
  75     f.write('GZ\n')
  76 f.close()
  77
  78 f = gzip.GzipFile(filename, 'r')
  79 verify(f.myfileobj.mode == 'rb')
  80 f.close()
  81
  82 os.unlink(filename)