Lib/test/test_file.py

   1 import sys
   2 import os
   3 from array import array
   4
   5 from test.test_support import verify, TESTFN, TestFailed
   6 from UserList import UserList
   7
   8 # verify expected attributes exist
   9 f = file(TESTFN, 'w')
  10 softspace = f.softspace
  11 f.name     # merely shouldn't blow up
  12 f.mode     # ditto
  13 f.closed   # ditto
  14
  15 # verify softspace is writable
  16 f.softspace = softspace    # merely shouldn't blow up
  17
  18 # verify the others aren't
  19 for attr in 'name', 'mode', 'closed':
  20     try:
  21         setattr(f, attr, 'oops')
  22     except TypeError:
  23         pass
  24     else:
  25         raise TestFailed('expected TypeError setting file attr %r' % attr)
  26 f.close()
  27
  28 # verify writelines with instance sequence
  29 l = UserList(['1', '2'])
  30 f = open(TESTFN, 'wb')
  31 f.writelines(l)
  32 f.close()
  33 f = open(TESTFN, 'rb')
  34 buf = f.read()
  35 f.close()
  36 verify(buf == '12')
  37
  38 # verify readinto
  39 a = array('c', 'x'*10)
  40 f = open(TESTFN, 'rb')
  41 n = f.readinto(a)
  42 f.close()
  43 verify(buf == a.tostring()[:n])
  44
  45 # verify writelines with integers
  46 f = open(TESTFN, 'wb')
  47 try:
  48     f.writelines([1, 2, 3])
  49 except TypeError:
  50     pass
  51 else:
  52     print "writelines accepted sequence of integers"
  53 f.close()
  54
  55 # verify writelines with integers in UserList
  56 f = open(TESTFN, 'wb')
  57 l = UserList([1,2,3])
  58 try:
  59     f.writelines(l)
  60 except TypeError:
  61     pass
  62 else:
  63     print "writelines accepted sequence of integers"
  64 f.close()
  65
  66 # verify writelines with non-string object
  67 class NonString: pass
  68
  69 f = open(TESTFN, 'wb')
  70 try:
  71     f.writelines([NonString(), NonString()])
  72 except TypeError:
  73     pass
  74 else:
  75     print "writelines accepted sequence of non-string objects"
  76 f.close()
  77
  78 # verify that we get a sensible error message for bad mode argument
  79 bad_mode = "qwerty"
  80 try:
  81     open(TESTFN, bad_mode)
  82 except IOError, msg:
  83     if msg[0] != 0:
  84         s = str(msg)
  85         if s.find(TESTFN) != -1 or s.find(bad_mode) == -1:
  86             print "bad error message for invalid mode: %s" % s
  87     # if msg[0] == 0, we're probably on Windows where there may be
  88     # no obvious way to discover why open() failed.
  89 else:
  90     print "no error for invalid mode: %s" % bad_mode
  91
  92 f = open(TESTFN)
  93 if f.name != TESTFN:
  94     raise TestFailed, 'file.name should be "%s"' % TESTFN
  95 if f.isatty():
  96     raise TestFailed, 'file.isatty() should be false'
  97
  98 if f.closed:
  99     raise TestFailed, 'file.closed should be false'
 100
 101 try:
 102     f.readinto("")
 103 except TypeError:
 104     pass
 105 else:
 106     raise TestFailed, 'file.readinto("") should raise a TypeError'
 107
 108 f.close()
 109 if not f.closed:
 110     raise TestFailed, 'file.closed should be true'
 111
 112 # make sure that explicitly setting the buffer size doesn't cause
 113 # misbehaviour especially with repeated close() calls
 114 for s in (-1, 0, 1, 512):
 115     try:
 116         f = open(TESTFN, 'w', s)
 117         f.write(str(s))
 118         f.close()
 119         f.close()
 120         f = open(TESTFN, 'r', s)
 121         d = int(f.read())
 122         f.close()
 123         f.close()
 124     except IOError, msg:
 125         raise TestFailed, 'error setting buffer size %d: %s' % (s, str(msg))
 126     if d != s:
 127         raise TestFailed, 'readback failure using buffer size %d'
 128
 129 methods = ['fileno', 'flush', 'isatty', 'next', 'read', 'readinto',
 130            'readline', 'readlines', 'seek', 'tell', 'truncate', 'write',
 131            'xreadlines', '__iter__']
 132 if sys.platform.startswith('atheos'):
 133     methods.remove('truncate')
 134
 135 for methodname in methods:
 136     method = getattr(f, methodname)
 137     try:
 138         method()
 139     except ValueError:
 140         pass
 141     else:
 142         raise TestFailed, 'file.%s() on a closed file should raise a ValueError' % methodname
 143
 144 try:
 145     f.writelines([])
 146 except ValueError:
 147     pass
 148 else:
 149     raise TestFailed, 'file.writelines([]) on a closed file should raise a ValueError'
 150
 151 os.unlink(TESTFN)