text: import os
  import array
  import unittest
  import struct
  import inspect
  from test.test_support import run_unittest, check_warnings, check_py3k_warnings
  
  import sys
  ISBIGENDIAN = sys.byteorder == "big"
  IS32BIT = sys.maxsize == 0x7fffffff
  
  integer_codes = 'b', 'B', 'h', 'H', 'i', 'I', 'l', 'L', 'q', 'Q'
  
  testmod_filename = os.path.splitext(__file__)[0] + '.py'
  # Native 'q' packing isn't available on systems that don't have the C
  # long long type.
  try:
      struct.pack('q', 5)
  except struct.error:
      HAVE_LONG_LONG = False
  else:
      HAVE_LONG_LONG = True
  
  def string_reverse(s):
      return "".join(reversed(s))
  
  def bigendian_to_native(value):
      if ISBIGENDIAN:
          return value
      else:
          return string_reverse(value)
  
  class StructTest(unittest.TestCase):
  
      def check_float_coerce(self, format, number):
          # SF bug 1530559. struct.pack raises TypeError where it used
          # to convert.
          with check_warnings((".*integer argument expected, got float",
                               DeprecationWarning)) as w:
              got = struct.pack(format, number)
          lineno = inspect.currentframe().f_lineno - 1
          self.assertEqual(w.filename, testmod_filename)
          self.assertEqual(w.lineno, lineno)
          self.assertEqual(len(w.warnings), 1)
          expected = struct.pack(format, int(number))
          self.assertEqual(got, expected)
  
      def test_isbigendian(self):
          self.assertEqual((struct.pack('=i', 1)[0] == chr(0)), ISBIGENDIAN)
  
      def test_consistence(self):
          self.assertRaises(struct.error, struct.calcsize, 'Z')
  
          sz = struct.calcsize('i')
          self.assertEqual(sz * 3, struct.calcsize('iii'))
  
          fmt = 'cbxxxxxxhhhhiillffd?'
          fmt3 = '3c3b18x12h6i6l6f3d3?'
          sz = struct.calcsize(fmt)
          sz3 = struct.calcsize(fmt3)
          self.assertEqual(sz * 3, sz3)
  
          self.assertRaises(struct.error, struct.pack, 'iii', 3)
          self.assertRaises(struct.error, struct.pack, 'i', 3, 3, 3)
          self.assertRaises(struct.error, struct.pack, 'i', 'foo')
          self.assertRaises(struct.error, struct.pack, 'P', 'foo')
          self.assertRaises(struct.error, struct.unpack, 'd', 'flap')
          s = struct.pack('ii', 1, 2)
          self.assertRaises(struct.error, struct.unpack, 'iii', s)
          self.assertRaises(struct.error, struct.unpack, 'i', s)
  
      def test_transitiveness(self):
          c = 'a'
          b = 1
          h = 255
          i = 65535
          l = 65536
          f = 3.1415
          d = 3.1415
          t = True
  
          for prefix in ('', '@', '<', '>', '=', '!'):
              for format in ('xcbhilfd?', 'xcBHILfd?'):
                  format = prefix + format
                  s = struct.pack(format, c, b, h, i, l, f, d, t)
                  cp, bp, hp, ip, lp, fp, dp, tp = struct.unpack(format, s)
                  self.assertEqual(cp, c)
                  self.assertEqual(bp, b)
                  self.assertEqual(hp, h)
                  self.assertEqual(ip, i)
                  self.assertEqual(lp, l)
                  self.assertEqual(int(100 * fp), int(100 * f))
                  self.assertEqual(int(100 * dp), int(100 * d))
                  self.assertEqual(tp, t)
  
      def test_new_features(self):
          # Test some of the new features in detail
          # (format, argument, big-endian result, little-endian result, asymmetric)
          tests = [
              ('c', 'a', 'a', 'a', 0),
              ('xc', 'a', '\0a', '\0a', 0),
              ('cx', 'a', 'a\0', 'a\0', 0),
              ('s', 'a', 'a', 'a', 0),
              ('0s', 'helloworld', '', '', 1),
              ('1s', 'helloworld', 'h', 'h', 1),
              ('9s', 'helloworld', 'helloworl', 'helloworl', 1),
              ('10s', 'helloworld', 'helloworld', 'helloworld', 0),
              ('11s', 'helloworld', 'helloworld\0', 'helloworld\0', 1),
              ('20s', 'helloworld', 'helloworld'+10*'\0', 'helloworld'+10*'\0', 1),
              ('b', 7, '\7', '\7', 0),
              ('b', -7, '\371', '\371', 0),
              ('B', 7, '\7', '\7', 0),
              ('B', 249, '\371', '\371', 0),
              ('h', 700, '\002\274', '\274\002', 0),
              ('h', -700, '\375D', 'D\375', 0),
              ('H', 700, '\002\274', '\274\002', 0),
              ('H', 0x10000-700, '\375D', 'D\375', 0),
              ('i', 70000000, '\004,\035\200', '\200\035,\004', 0),
              ('i', -70000000, '\373\323\342\200', '\200\342\323\373', 0),
              ('I', 70000000L, '\004,\035\200', '\200\035,\004', 0),
              ('I', 0x100000000L-70000000, '\373\323\342\200', '\200\342\323\373', 0),
              ('l', 70000000, '\004,\035\200', '\200\035,\004', 0),
              ('l', -70000000, '\373\323\342\200', '\200\342\323\373', 0),
              ('L', 70000000L, '\004,\035\200', '\200\035,\004', 0),
              ('L', 0x100000000L-70000000, '\373\323\342\200', '\200\342\323\373', 0),
              ('f', 2.0, '@\000\000\000', '\000\000\000@', 0),
              ('d', 2.0, '@\000\000\000\000\000\000\000',
                         '\000\000\000\000\000\000\000@', 0),
              ('f', -2.0, '\300\000\000\000', '\000\000\000\300', 0),
              ('d', -2.0, '\300\000\000\000\000\000\000\000',
                         '\000\000\000\000\000\000\000\300', 0),
                  ('?', 0, '\0', '\0', 0),
                  ('?', 3, '\1', '\1', 1),
                  ('?', True, '\1', '\1', 0),
                  ('?', [], '\0', '\0', 1),
                  ('?', (1,), '\1', '\1', 1),
          ]
  
          for fmt, arg, big, lil, asy in tests:
              for (xfmt, exp) in [('>'+fmt, big), ('!'+fmt, big), ('<'+fmt, lil),
                                  ('='+fmt, ISBIGENDIAN and big or lil)]:
                  res = struct.pack(xfmt, arg)
                  self.assertEqual(res, exp)
                  self.assertEqual(struct.calcsize(xfmt), len(res))
                  rev = struct.unpack(xfmt, res)[0]
                  if rev != arg:
                      self.assertTrue(asy)
  
      def test_calcsize(self):
          expected_size = {
              'b': 1, 'B': 1,
              'h': 2, 'H': 2,
              'i': 4, 'I': 4,
              'l': 4, 'L': 4,
              'q': 8, 'Q': 8,
              }
  
          # standard integer sizes
          for code in integer_codes:
              for byteorder in ('=', '<', '>', '!'):
                  format = byteorder+code
                  size = struct.calcsize(format)
                  self.assertEqual(size, expected_size[code])
  
          # native integer sizes, except 'q' and 'Q'
          for format_pair in ('bB', 'hH', 'iI', 'lL'):
              for byteorder in ['', '@']:
                  signed_size = struct.calcsize(byteorder + format_pair[0])
                  unsigned_size = struct.calcsize(byteorder + format_pair[1])
                  self.assertEqual(signed_size, unsigned_size)
  
          # bounds for native integer sizes
          self.assertEqual(struct.calcsize('b'), 1)
          self.assertLessEqual(2, struct.calcsize('h'))
          self.assertLessEqual(4, struct.calcsize('l'))
          self.assertLessEqual(struct.calcsize('h'), struct.calcsize('i'))
          self.assertLessEqual(struct.calcsize('i'), struct.calcsize('l'))
  
          # tests for native 'q' and 'Q' when applicable
          if HAVE_LONG_LONG:
              self.assertEqual(struct.calcsize('q'), struct.calcsize('Q'))
              self.assertLessEqual(8, struct.calcsize('q'))
              self.assertLessEqual(struct.calcsize('l'), struct.calcsize('q'))
  
      def test_integers(self):
          # Integer tests (bBhHiIlLqQ).
          import binascii
  
          class IntTester(unittest.TestCase):
              def __init__(self, format):
                  super(IntTester, self).__init__(methodName='test_one')
                  self.format = format
                  self.code = format[-1]
                  self.direction = format[:-1]
                  if not self.direction in ('', '@', '=', '<', '>', '!'):
                      raise ValueError("unrecognized packing direction: %s" %
                                       self.direction)
                  self.bytesize = struct.calcsize(format)
                  self.bitsize = self.bytesize * 8
                  if self.code in tuple('bhilq'):
                      self.signed = True
                      self.min_value = -(2L**(self.bitsize-1))
                      self.max_value = 2L**(self.bitsize-1) - 1
                  elif self.code in tuple('BHILQ'):
                      self.signed = False
                      self.min_value = 0
                      self.max_value = 2L**self.bitsize - 1
                  else:
                      raise ValueError("unrecognized format code: %s" %
                                       self.code)
  
              def test_one(self, x, pack=struct.pack,
                                    unpack=struct.unpack,
                                    unhexlify=binascii.unhexlify):
  
                  format = self.format
                  if self.min_value <= x <= self.max_value:
                      expected = long(x)
                      if self.signed and x < 0:
                          expected += 1L << self.bitsize
                      self.assertGreaterEqual(expected, 0)
                      expected = '%x' % expected
                      if len(expected) & 1:
                          expected = "0" + expected
                      expected = unhexlify(expected)
                      expected = ("\x00" * (self.bytesize - len(expected)) +
                                  expected)
                      if (self.direction == '<' or
                          self.direction in ('', '@', '=') and not ISBIGENDIAN):
                          expected = string_reverse(expected)
                      self.assertEqual(len(expected), self.bytesize)
  
                      # Pack work?
                      got = pack(format, x)
                      self.assertEqual(got, expected)
  
                      # Unpack work?
                      retrieved = unpack(format, got)[0]
                      self.assertEqual(x, retrieved)
  
                      # Adding any byte should cause a "too big" error.
                      self.assertRaises((struct.error, TypeError), unpack, format,
                                                                   '\x01' + got)
                  else:
                      # x is out of range -- verify pack realizes that.
                      self.assertRaises(struct.error, pack, format, x)
  
              def run(self):
                  from random import randrange
  
                  # Create all interesting powers of 2.
                  values = []
                  for exp in range(self.bitsize + 3):
                      values.append(1L << exp)
  
                  # Add some random values.
                  for i in range(self.bitsize):
                      val = 0L
                      for j in range(self.bytesize):
                          val = (val << 8) | randrange(256)
                      values.append(val)
  
                  # Values absorbed from other tests
                  values.extend([300, 700000, sys.maxint*4])
  
                  # Try all those, and their negations, and +-1 from
                  # them.  Note that this tests all power-of-2
                  # boundaries in range, and a few out of range, plus
                  # +-(2**n +- 1).
                  for base in values:
                      for val in -base, base:
                          for incr in -1, 0, 1:
                              x = val + incr
                              self.test_one(int(x))
                              self.test_one(long(x))
  
                  # Some error cases.
                  class NotAnIntNS(object):
                      def __int__(self):
                          return 42
  
                      def __long__(self):
                          return 1729L
  
                  class NotAnIntOS:
                      def __int__(self):
                          return 85
  
                      def __long__(self):
                          return -163L
  
                  # Objects with an '__index__' method should be allowed
                  # to pack as integers.  That is assuming the implemented
                  # '__index__' method returns and 'int' or 'long'.
                  class Indexable(object):
                      def __init__(self, value):
                          self._value = value
  
                      def __index__(self):
                          return self._value
  
                  # If the '__index__' method raises a type error, then
                  # '__int__' should be used with a deprecation warning.
                  class BadIndex(object):
                      def __index__(self):
                          raise TypeError
  
                      def __int__(self):
                          return 42
  
                  self.assertRaises((TypeError, struct.error),
                                    struct.pack, self.format,
                                    "a string")
                  self.assertRaises((TypeError, struct.error),
                                    struct.pack, self.format,
                                    randrange)
                  with check_warnings(("integer argument expected, "
                                       "got non-integer", DeprecationWarning)):
                      self.assertRaises((TypeError, struct.error),
                                        struct.pack, self.format,
                                        3+42j)
  
                  # an attempt to convert a non-integer (with an
                  # implicit conversion via __int__) should succeed,
                  # with a DeprecationWarning
                  for nonint in NotAnIntNS(), NotAnIntOS(), BadIndex():
                      with check_warnings((".*integer argument expected, got non"
                                           "-integer", DeprecationWarning)) as w:
                          got = struct.pack(self.format, nonint)
                      lineno = inspect.currentframe().f_lineno - 1
                      self.assertEqual(w.filename, testmod_filename)
                      self.assertEqual(w.lineno, lineno)
                      self.assertEqual(len(w.warnings), 1)
                      expected = struct.pack(self.format, int(nonint))
                      self.assertEqual(got, expected)
  
                  # Check for legitimate values from '__index__'.
                  for obj in (Indexable(0), Indexable(10), Indexable(17),
                              Indexable(42), Indexable(100), Indexable(127)):
                      try:
                          struct.pack(format, obj)
                      except:
                          self.fail("integer code pack failed on object "
                                    "with '__index__' method")
  
                  # Check for bogus values from '__index__'.
                  for obj in (Indexable('a'), Indexable(u'b'), Indexable(None),
                              Indexable({'a': 1}), Indexable([1, 2, 3])):
                      self.assertRaises((TypeError, struct.error),
                                        struct.pack, self.format,
                                        obj)
  
          byteorders = '', '@', '=', '<', '>', '!'
          for code in integer_codes:
              for byteorder in byteorders:
                  if (byteorder in ('', '@') and code in ('q', 'Q') and
                      not HAVE_LONG_LONG):
                      continue
                  format = byteorder+code
                  t = IntTester(format)
                  t.run()
  
      def test_p_code(self):
          # Test p ("Pascal string") code.
          for code, input, expected, expectedback in [
                  ('p','abc', '\x00', ''),
                  ('1p', 'abc', '\x00', ''),
                  ('2p', 'abc', '\x01a', 'a'),
                  ('3p', 'abc', '\x02ab', 'ab'),
                  ('4p', 'abc', '\x03abc', 'abc'),
                  ('5p', 'abc', '\x03abc\x00', 'abc'),
                  ('6p', 'abc', '\x03abc\x00\x00', 'abc'),
                  ('1000p', 'x'*1000, '\xff' + 'x'*999, 'x'*255)]:
              got = struct.pack(code, input)
              self.assertEqual(got, expected)
              (got,) = struct.unpack(code, got)
              self.assertEqual(got, expectedback)
  
      def test_705836(self):
          # SF bug 705836.  "<f" and ">f" had a severe rounding bug, where a carry
          # from the low-order discarded bits could propagate into the exponent
          # field, causing the result to be wrong by a factor of 2.
          import math
  
          for base in range(1, 33):
              # smaller <- largest representable float less than base.
              delta = 0.5
              while base - delta / 2.0 != base:
                  delta /= 2.0
              smaller = base - delta
              # Packing this rounds away a solid string of trailing 1 bits.
              packed = struct.pack("<f", smaller)
              unpacked = struct.unpack("<f", packed)[0]
              # This failed at base = 2, 4, and 32, with unpacked = 1, 2, and
              # 16, respectively.
              self.assertEqual(base, unpacked)
              bigpacked = struct.pack(">f", smaller)
              self.assertEqual(bigpacked, string_reverse(packed))
              unpacked = struct.unpack(">f", bigpacked)[0]
              self.assertEqual(base, unpacked)
  
          # Largest finite IEEE single.
          big = (1 << 24) - 1
          big = math.ldexp(big, 127 - 23)
          packed = struct.pack(">f", big)
          unpacked = struct.unpack(">f", packed)[0]
          self.assertEqual(big, unpacked)
  
          # The same, but tack on a 1 bit so it rounds up to infinity.
          big = (1 << 25) - 1
          big = math.ldexp(big, 127 - 24)
          self.assertRaises(OverflowError, struct.pack, ">f", big)
  
      def test_1530559(self):
          # SF bug 1530559. struct.pack raises TypeError where it used to convert.
          for endian in ('', '>', '<'):
              for fmt in integer_codes:
                  self.check_float_coerce(endian + fmt, 1.0)
                  self.check_float_coerce(endian + fmt, 1.5)
  
      def test_unpack_from(self, cls=str):
          data = cls('abcd01234')
          fmt = '4s'
          s = struct.Struct(fmt)
  
          self.assertEqual(s.unpack_from(data), ('abcd',))
          self.assertEqual(struct.unpack_from(fmt, data), ('abcd',))
          for i in xrange(6):
              self.assertEqual(s.unpack_from(data, i), (data[i:i+4],))
              self.assertEqual(struct.unpack_from(fmt, data, i), (data[i:i+4],))
          for i in xrange(6, len(data) + 1):
              self.assertRaises(struct.error, s.unpack_from, data, i)
              self.assertRaises(struct.error, struct.unpack_from, fmt, data, i)
  
      def test_pack_into(self):
          test_string = 'Reykjavik rocks, eow!'
          writable_buf = array.array('c', ' '*100)
          fmt = '21s'
          s = struct.Struct(fmt)
  
          # Test without offset
          s.pack_into(writable_buf, 0, test_string)
          from_buf = writable_buf.tostring()[:len(test_string)]
          self.assertEqual(from_buf, test_string)
  
          # Test with offset.
          s.pack_into(writable_buf, 10, test_string)
          from_buf = writable_buf.tostring()[:len(test_string)+10]
          self.assertEqual(from_buf, test_string[:10] + test_string)
  
          # Go beyond boundaries.
          small_buf = array.array('c', ' '*10)
          self.assertRaises(struct.error, s.pack_into, small_buf, 0, test_string)
          self.assertRaises(struct.error, s.pack_into, small_buf, 2, test_string)
  
          # Test bogus offset (issue 3694)
          sb = small_buf
          self.assertRaises(TypeError, struct.pack_into, b'1', sb, None)
  
      def test_pack_into_fn(self):
          test_string = 'Reykjavik rocks, eow!'
          writable_buf = array.array('c', ' '*100)
          fmt = '21s'
          pack_into = lambda *args: struct.pack_into(fmt, *args)
  
          # Test without offset.
          pack_into(writable_buf, 0, test_string)
          from_buf = writable_buf.tostring()[:len(test_string)]
          self.assertEqual(from_buf, test_string)
  
          # Test with offset.
          pack_into(writable_buf, 10, test_string)
          from_buf = writable_buf.tostring()[:len(test_string)+10]
          self.assertEqual(from_buf, test_string[:10] + test_string)
  
          # Go beyond boundaries.
          small_buf = array.array('c', ' '*10)
          self.assertRaises(struct.error, pack_into, small_buf, 0, test_string)
          self.assertRaises(struct.error, pack_into, small_buf, 2, test_string)
  
      def test_unpack_with_buffer(self):
          with check_py3k_warnings(("buffer.. not supported in 3.x",
                                    DeprecationWarning)):
              # SF bug 1563759: struct.unpack doesn't support buffer protocol objects
              data1 = array.array('B', '\x12\x34\x56\x78')
              data2 = buffer('......\x12\x34\x56\x78......', 6, 4)
              for data in [data1, data2]:
                  value, = struct.unpack('>I', data)
                  self.assertEqual(value, 0x12345678)
  
              self.test_unpack_from(cls=buffer)
  
      def test_bool(self):
          for prefix in tuple("<>!=")+('',):
              false = (), [], [], '', 0
              true = [1], 'test', 5, -1, 0xffffffffL+1, 0xffffffff//2
  
              falseFormat = prefix + '?' * len(false)
              packedFalse = struct.pack(falseFormat, *false)
              unpackedFalse = struct.unpack(falseFormat, packedFalse)
  
              trueFormat = prefix + '?' * len(true)
              packedTrue = struct.pack(trueFormat, *true)
              unpackedTrue = struct.unpack(trueFormat, packedTrue)
  
              self.assertEqual(len(true), len(unpackedTrue))
              self.assertEqual(len(false), len(unpackedFalse))
  
              for t in unpackedFalse:
                  self.assertFalse(t)
              for t in unpackedTrue:
                  self.assertTrue(t)
  
              packed = struct.pack(prefix+'?', 1)
  
              self.assertEqual(len(packed), struct.calcsize(prefix+'?'))
  
              if len(packed) != 1:
                  self.assertFalse(prefix, msg='encoded bool is not one byte: %r'
                                               %packed)
  
              for c in '\x01\x7f\xff\x0f\xf0':
                  self.assertTrue(struct.unpack('>?', c)[0])
  
      @unittest.skipUnless(IS32BIT, "Specific to 32bit machines")
      def test_crasher(self):
          self.assertRaises(MemoryError, struct.pack, "357913941c", "a")
  
      def test_count_overflow(self):
          hugecount = '{}b'.format(sys.maxsize+1)
          self.assertRaises(struct.error, struct.calcsize, hugecount)
  
          hugecount2 = '{}b{}H'.format(sys.maxsize//2, sys.maxsize//2)
          self.assertRaises(struct.error, struct.calcsize, hugecount2)
  
  def test_main():
      run_unittest(StructTest)
  
  if __name__ == '__main__':
      test_main()
  