text: import os
  import array
  import unittest
  import struct
  import inspect
  import warnings
  from test.test_support import run_unittest, check_warnings, _check_py3k_warnings
  
  
  from functools import wraps
  from test.test_support import TestFailed, verbose, run_unittest
  
  import sys
  ISBIGENDIAN = sys.byteorder == "big"
  IS32BIT = sys.maxsize == 0x7fffffff
  
  testmod_filename = os.path.splitext(__file__)[0] + '.py'
  try:
      import _struct
  except ImportError:
      PY_STRUCT_RANGE_CHECKING = 0
      PY_STRUCT_OVERFLOW_MASKING = 1
      PY_STRUCT_FLOAT_COERCE = 2
  else:
      PY_STRUCT_RANGE_CHECKING = getattr(_struct, '_PY_STRUCT_RANGE_CHECKING', 0)
      PY_STRUCT_OVERFLOW_MASKING = getattr(_struct, '_PY_STRUCT_OVERFLOW_MASKING', 0)
      PY_STRUCT_FLOAT_COERCE = getattr(_struct, '_PY_STRUCT_FLOAT_COERCE', 0)
  
  def string_reverse(s):
      return "".join(reversed(s))
  
  def bigendian_to_native(value):
      if ISBIGENDIAN:
          return value
      else:
          return string_reverse(value)
  
  def with_warning_restore(func):
      @wraps(func)
      def decorator(*args, **kw):
          with warnings.catch_warnings():
              # We need this function to warn every time, so stick an
              # unqualifed 'always' at the head of the filter list
              warnings.simplefilter("always")
              warnings.filterwarnings("error", category=DeprecationWarning)
              return func(*args, **kw)
      return decorator
  
  @with_warning_restore
  def deprecated_err(func, *args):
      try:
          func(*args)
      except (struct.error, TypeError):
          pass
      except DeprecationWarning:
          if not PY_STRUCT_OVERFLOW_MASKING:
              raise TestFailed, "%s%s expected to raise DeprecationWarning" % (
                  func.__name__, args)
      else:
          raise TestFailed, "%s%s did not raise error" % (
              func.__name__, args)
  
  
  class StructTest(unittest.TestCase):
  
      @with_warning_restore
      def check_float_coerce(self, format, number):
          # SF bug 1530559. struct.pack raises TypeError where it used to convert.
          if PY_STRUCT_FLOAT_COERCE == 2:
              # Test for pre-2.5 struct module
              with check_warnings((".*integer argument expected, got float",
                                  DeprecationWarning)) as w:
                  packed = struct.pack(format, number)
                  floored = struct.unpack(format, packed)[0]
              self.assertEqual(floored, int(number),
                               "did not correcly coerce float to int")
              return
          try:
              struct.pack(format, number)
          except (struct.error, TypeError):
              if PY_STRUCT_FLOAT_COERCE:
                  self.fail("expected DeprecationWarning for float coerce")
          except DeprecationWarning:
              if not PY_STRUCT_FLOAT_COERCE:
                  self.fail("expected to raise struct.error for float coerce")
          else:
              self.fail("did not raise error for float coerce")
  
      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_warnings_stacklevel(self):
          # Python versions between 2.6 and 2.6.5 were producing
          # warning messages at the wrong stacklevel.
          def inner(fn, *args):
              return inspect.currentframe().f_lineno, fn(*args)
  
          def check_warning_stacklevel(fn, *args):
              with warnings.catch_warnings(record=True) as w:
                  # "always" to make sure __warningregistry__ isn't affected
                  warnings.simplefilter("always")
                  lineno, result = inner(fn, *args)
              for warn in w:
                  self.assertEqual(warn.lineno, lineno)
  
          # out of range warnings
          check_warning_stacklevel(struct.pack, '<L', -1)
          check_warning_stacklevel(struct.pack, 'L', -1)
          check_warning_stacklevel(struct.pack, '<h', 65536)
          check_warning_stacklevel(struct.pack, '<l', 2**100)
  
          # float warnings
          check_warning_stacklevel(struct.pack, 'L', 3.1)
  
      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.assert_(asy)
  
      def test_native_qQ(self):
          # can't pack -1 as unsigned regardless
          self.assertRaises((struct.error, TypeError), struct.pack, "Q", -1)
          # can't pack string as 'q' regardless
          self.assertRaises(struct.error, struct.pack, "q", "a")
          # ditto, but 'Q'
          self.assertRaises(struct.error, struct.pack, "Q", "a")
  
          try:
              struct.pack("q", 5)
          except struct.error:
              # does not have native q/Q
              pass
          else:
              bytes = struct.calcsize('q')
              # The expected values here are in big-endian format, primarily
              # because I'm on a little-endian machine and so this is the
              # clearest way (for me) to force the code to get exercised.
              for format, input, expected in (
                      ('q', -1, '\xff' * bytes),
                      ('q', 0, '\x00' * bytes),
                      ('Q', 0, '\x00' * bytes),
                      ('q', 1L, '\x00' * (bytes-1) + '\x01'),
                      ('Q', (1L << (8*bytes))-1, '\xff' * bytes),
                      ('q', (1L << (8*bytes-1))-1, '\x7f' + '\xff' * (bytes - 1))):
                  got = struct.pack(format, input)
                  native_expected = bigendian_to_native(expected)
                  self.assertEqual(got, native_expected)
                  retrieved = struct.unpack(format, got)[0]
                  self.assertEqual(retrieved, input)
  
      def test_standard_integers(self):
          # Standard integer tests (bBhHiIlLqQ).
          import binascii
  
          class IntTester(unittest.TestCase):
  
              # XXX Most std integer modes fail to test for out-of-range.
              # The "i" and "l" codes appear to range-check OK on 32-bit boxes, but
              # fail to check correctly on some 64-bit ones (Tru64 Unix + Compaq C
              # reported by Mark Favas).
              BUGGY_RANGE_CHECK = "bBhHiIlL"
  
              def __init__(self, formatpair, bytesize):
                  self.assertEqual(len(formatpair), 2)
                  self.formatpair = formatpair
                  for direction in "<>!=":
                      for code in formatpair:
                          format = direction + code
                          self.assertEqual(struct.calcsize(format), bytesize)
                  self.bytesize = bytesize
                  self.bitsize = bytesize * 8
                  self.signed_code, self.unsigned_code = formatpair
                  self.unsigned_min = 0
                  self.unsigned_max = 2L**self.bitsize - 1
                  self.signed_min = -(2L**(self.bitsize-1))
                  self.signed_max = 2L**(self.bitsize-1) - 1
  
              def test_one(self, x, pack=struct.pack,
                                    unpack=struct.unpack,
                                    unhexlify=binascii.unhexlify):
                  # Try signed.
                  code = self.signed_code
                  if self.signed_min <= x <= self.signed_max:
                      # Try big-endian.
                      expected = long(x)
                      if x < 0:
                          expected += 1L << self.bitsize
                          self.assert_(expected > 0)
                      expected = hex(expected)[2:-1] # chop "0x" and trailing 'L'
                      if len(expected) & 1:
                          expected = "0" + expected
                      expected = unhexlify(expected)
                      expected = "\x00" * (self.bytesize - len(expected)) + expected
  
                      # Pack work?
                      format = ">" + code
                      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)
                      # Try little-endian.
                      format = "<" + code
                      expected = string_reverse(expected)
  
                      # 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.
                      if not PY_STRUCT_RANGE_CHECKING and code in self.BUGGY_RANGE_CHECK:
                          if verbose:
                              print "Skipping buggy range check for code", code
                      else:
                          deprecated_err(pack, ">" + code, x)
                          deprecated_err(pack, "<" + code, x)
  
                  # Much the same for unsigned.
                  code = self.unsigned_code
                  if self.unsigned_min <= x <= self.unsigned_max:
                      # Try big-endian.
                      format = ">" + code
                      expected = long(x)
                      expected = hex(expected)[2:-1] # chop "0x" and trailing 'L'
                      if len(expected) & 1:
                          expected = "0" + expected
                      expected = unhexlify(expected)
                      expected = "\x00" * (self.bytesize - len(expected)) + expected
  
                      # 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)
  
                      # Try little-endian.
                      format = "<" + code
                      expected = string_reverse(expected)
  
                      # 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.
                      if not PY_STRUCT_RANGE_CHECKING and code in self.BUGGY_RANGE_CHECK:
                          if verbose:
                              print "Skipping buggy range check for code", code
                      else:
                          deprecated_err(pack, ">" + code, x)
                          deprecated_err(pack, "<" + code, 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)
  
                  # 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
                              try:
                                  x = int(x)
                              except OverflowError:
                                  pass
                              self.test_one(x)
  
                  # Some error cases.
                  for direction in "<>":
                      for code in self.formatpair:
                          for badobject in "a string", 3+42j, randrange:
                              self.assertRaises((struct.error, TypeError),
                                                 struct.pack, direction + code,
                                                 badobject)
  
          for args in [("bB", 1),
                       ("hH", 2),
                       ("iI", 4),
                       ("lL", 4),
                       ("qQ", 8)]:
              t = IntTester(*args)
              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)
  
      if PY_STRUCT_RANGE_CHECKING:
          def test_1229380(self):
              # SF bug 1229380. No struct.pack exception for some out of
              # range integers
              import sys
              for endian in ('', '>', '<'):
                  for cls in (int, long):
                      for fmt in ('B', 'H', 'I', 'L'):
                          deprecated_err(struct.pack, endian + fmt, cls(-1))
  
                      deprecated_err(struct.pack, endian + 'B', cls(300))
                      deprecated_err(struct.pack, endian + 'H', cls(70000))
  
                  deprecated_err(struct.pack, endian + 'I', sys.maxint * 4L)
                  deprecated_err(struct.pack, endian + 'L', sys.maxint * 4L)
  
      def XXXtest_1530559(self):
          # XXX This is broken: see the bug report
          # SF bug 1530559. struct.pack raises TypeError where it used to convert.
          for endian in ('', '>', '<'):
              for fmt in ('B', 'H', 'I', 'L', 'b', 'h', 'i', 'l'):
                  self.check_float_coerce(endian + fmt, 1.0)
                  self.check_float_coerce(endian + fmt, 1.5)
  
      def test_issue4228(self):
          # Packing a long may yield either 32 or 64 bits
          with check_warnings(quiet=True):
              x = struct.pack('L', -1)[:4]
          self.assertEqual(x, '\xff'*4)
  
      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])
  
      if IS32BIT:
          def test_crasher(self):
              self.assertRaises(MemoryError, struct.pack, "357913941c", "a")
  
      def test_count_overflow(self):
          hugecount = '{0}b'.format(sys.maxsize+1)
          self.assertRaises(struct.error, struct.calcsize, hugecount)
  
          hugecount2 = '{0}b{1}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()
  