| from collections import abc |
| import array |
| import math |
| import operator |
| import unittest |
| import struct |
| import sys |
| |
| from test import support |
| |
| ISBIGENDIAN = sys.byteorder == "big" |
| |
| integer_codes = 'b', 'B', 'h', 'H', 'i', 'I', 'l', 'L', 'q', 'Q', 'n', 'N' |
| byteorders = '', '@', '=', '<', '>', '!' |
| |
| def iter_integer_formats(byteorders=byteorders): |
| for code in integer_codes: |
| for byteorder in byteorders: |
| if (byteorder not in ('', '@') and code in ('n', 'N')): |
| continue |
| yield code, byteorder |
| |
| def string_reverse(s): |
| return s[::-1] |
| |
| def bigendian_to_native(value): |
| if ISBIGENDIAN: |
| return value |
| else: |
| return string_reverse(value) |
| |
| class StructTest(unittest.TestCase): |
| def test_isbigendian(self): |
| self.assertEqual((struct.pack('=i', 1)[0] == 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((TypeError, struct.error), struct.pack, 'i', 'foo') |
| self.assertRaises((TypeError, struct.error), struct.pack, 'P', 'foo') |
| self.assertRaises(struct.error, struct.unpack, 'd', b'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 = b'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', b'a', b'a', b'a', 0), |
| ('xc', b'a', b'\0a', b'\0a', 0), |
| ('cx', b'a', b'a\0', b'a\0', 0), |
| ('s', b'a', b'a', b'a', 0), |
| ('0s', b'helloworld', b'', b'', 1), |
| ('1s', b'helloworld', b'h', b'h', 1), |
| ('9s', b'helloworld', b'helloworl', b'helloworl', 1), |
| ('10s', b'helloworld', b'helloworld', b'helloworld', 0), |
| ('11s', b'helloworld', b'helloworld\0', b'helloworld\0', 1), |
| ('20s', b'helloworld', b'helloworld'+10*b'\0', b'helloworld'+10*b'\0', 1), |
| ('b', 7, b'\7', b'\7', 0), |
| ('b', -7, b'\371', b'\371', 0), |
| ('B', 7, b'\7', b'\7', 0), |
| ('B', 249, b'\371', b'\371', 0), |
| ('h', 700, b'\002\274', b'\274\002', 0), |
| ('h', -700, b'\375D', b'D\375', 0), |
| ('H', 700, b'\002\274', b'\274\002', 0), |
| ('H', 0x10000-700, b'\375D', b'D\375', 0), |
| ('i', 70000000, b'\004,\035\200', b'\200\035,\004', 0), |
| ('i', -70000000, b'\373\323\342\200', b'\200\342\323\373', 0), |
| ('I', 70000000, b'\004,\035\200', b'\200\035,\004', 0), |
| ('I', 0x100000000-70000000, b'\373\323\342\200', b'\200\342\323\373', 0), |
| ('l', 70000000, b'\004,\035\200', b'\200\035,\004', 0), |
| ('l', -70000000, b'\373\323\342\200', b'\200\342\323\373', 0), |
| ('L', 70000000, b'\004,\035\200', b'\200\035,\004', 0), |
| ('L', 0x100000000-70000000, b'\373\323\342\200', b'\200\342\323\373', 0), |
| ('f', 2.0, b'@\000\000\000', b'\000\000\000@', 0), |
| ('d', 2.0, b'@\000\000\000\000\000\000\000', |
| b'\000\000\000\000\000\000\000@', 0), |
| ('f', -2.0, b'\300\000\000\000', b'\000\000\000\300', 0), |
| ('d', -2.0, b'\300\000\000\000\000\000\000\000', |
| b'\000\000\000\000\000\000\000\300', 0), |
| ('?', 0, b'\0', b'\0', 0), |
| ('?', 3, b'\1', b'\1', 1), |
| ('?', True, b'\1', b'\1', 0), |
| ('?', [], b'\0', b'\0', 1), |
| ('?', (1,), b'\1', b'\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, byteorder in iter_integer_formats(('=', '<', '>', '!')): |
| format = byteorder+code |
| size = struct.calcsize(format) |
| self.assertEqual(size, expected_size[code]) |
| |
| # native integer sizes |
| native_pairs = 'bB', 'hH', 'iI', 'lL', 'nN', 'qQ' |
| for format_pair in native_pairs: |
| 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')) |
| self.assertLessEqual(8, struct.calcsize('q')) |
| self.assertLessEqual(struct.calcsize('l'), struct.calcsize('q')) |
| self.assertGreaterEqual(struct.calcsize('n'), struct.calcsize('i')) |
| self.assertGreaterEqual(struct.calcsize('n'), struct.calcsize('P')) |
| |
| def test_integers(self): |
| # Integer tests (bBhHiIlLqQnN). |
| 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.byteorder = format[:-1] |
| if not self.byteorder in byteorders: |
| raise ValueError("unrecognized packing byteorder: %s" % |
| self.byteorder) |
| self.bytesize = struct.calcsize(format) |
| self.bitsize = self.bytesize * 8 |
| if self.code in tuple('bhilqn'): |
| self.signed = True |
| self.min_value = -(2**(self.bitsize-1)) |
| self.max_value = 2**(self.bitsize-1) - 1 |
| elif self.code in tuple('BHILQN'): |
| self.signed = False |
| self.min_value = 0 |
| self.max_value = 2**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 = x |
| if self.signed and x < 0: |
| expected += 1 << self.bitsize |
| self.assertGreaterEqual(expected, 0) |
| expected = '%x' % expected |
| if len(expected) & 1: |
| expected = "0" + expected |
| expected = expected.encode('ascii') |
| expected = unhexlify(expected) |
| expected = (b"\x00" * (self.bytesize - len(expected)) + |
| expected) |
| if (self.byteorder == '<' or |
| self.byteorder 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, |
| b'\x01' + got) |
| else: |
| # x is out of range -- verify pack realizes that. |
| self.assertRaises((OverflowError, ValueError, 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(1 << exp) |
| |
| # Add some random values. |
| for i in range(self.bitsize): |
| val = 0 |
| for j in range(self.bytesize): |
| val = (val << 8) | randrange(256) |
| values.append(val) |
| |
| # Values absorbed from other tests |
| values.extend([300, 700000, sys.maxsize*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(x) |
| |
| # Some error cases. |
| class NotAnInt: |
| def __int__(self): |
| return 42 |
| |
| # Objects with an '__index__' method should be allowed |
| # to pack as integers. That is assuming the implemented |
| # '__index__' method returns an 'int'. |
| 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) |
| self.assertRaises((TypeError, struct.error), |
| struct.pack, self.format, |
| 3+42j) |
| self.assertRaises((TypeError, struct.error), |
| struct.pack, self.format, |
| NotAnInt()) |
| self.assertRaises((TypeError, struct.error), |
| struct.pack, self.format, |
| BadIndex()) |
| |
| # 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(b'a'), Indexable('b'), Indexable(None), |
| Indexable({'a': 1}), Indexable([1, 2, 3])): |
| self.assertRaises((TypeError, struct.error), |
| struct.pack, self.format, |
| obj) |
| |
| for code, byteorder in iter_integer_formats(): |
| format = byteorder+code |
| t = IntTester(format) |
| t.run() |
| |
| def test_nN_code(self): |
| # n and N don't exist in standard sizes |
| def assertStructError(func, *args, **kwargs): |
| with self.assertRaises(struct.error) as cm: |
| func(*args, **kwargs) |
| self.assertIn("bad char in struct format", str(cm.exception)) |
| for code in 'nN': |
| for byteorder in ('=', '<', '>', '!'): |
| format = byteorder+code |
| assertStructError(struct.calcsize, format) |
| assertStructError(struct.pack, format, 0) |
| assertStructError(struct.unpack, format, b"") |
| |
| def test_p_code(self): |
| # Test p ("Pascal string") code. |
| for code, input, expected, expectedback in [ |
| ('p', b'abc', b'\x00', b''), |
| ('1p', b'abc', b'\x00', b''), |
| ('2p', b'abc', b'\x01a', b'a'), |
| ('3p', b'abc', b'\x02ab', b'ab'), |
| ('4p', b'abc', b'\x03abc', b'abc'), |
| ('5p', b'abc', b'\x03abc\x00', b'abc'), |
| ('6p', b'abc', b'\x03abc\x00\x00', b'abc'), |
| ('1000p', b'x'*1000, b'\xff' + b'x'*999, b'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. |
| 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): |
| for code, byteorder in iter_integer_formats(): |
| format = byteorder + code |
| self.assertRaises(struct.error, struct.pack, format, 1.0) |
| self.assertRaises(struct.error, struct.pack, format, 1.5) |
| self.assertRaises(struct.error, struct.pack, 'P', 1.0) |
| self.assertRaises(struct.error, struct.pack, 'P', 1.5) |
| |
| def test_unpack_from(self): |
| test_string = b'abcd01234' |
| fmt = '4s' |
| s = struct.Struct(fmt) |
| for cls in (bytes, bytearray): |
| data = cls(test_string) |
| self.assertEqual(s.unpack_from(data), (b'abcd',)) |
| self.assertEqual(s.unpack_from(data, 2), (b'cd01',)) |
| self.assertEqual(s.unpack_from(data, 4), (b'0123',)) |
| for i in range(6): |
| self.assertEqual(s.unpack_from(data, i), (data[i:i+4],)) |
| for i in range(6, len(test_string) + 1): |
| self.assertRaises(struct.error, s.unpack_from, data, i) |
| for cls in (bytes, bytearray): |
| data = cls(test_string) |
| self.assertEqual(struct.unpack_from(fmt, data), (b'abcd',)) |
| self.assertEqual(struct.unpack_from(fmt, data, 2), (b'cd01',)) |
| self.assertEqual(struct.unpack_from(fmt, data, 4), (b'0123',)) |
| for i in range(6): |
| self.assertEqual(struct.unpack_from(fmt, data, i), (data[i:i+4],)) |
| for i in range(6, len(test_string) + 1): |
| self.assertRaises(struct.error, struct.unpack_from, fmt, data, i) |
| |
| # keyword arguments |
| self.assertEqual(s.unpack_from(buffer=test_string, offset=2), |
| (b'cd01',)) |
| |
| def test_pack_into(self): |
| test_string = b'Reykjavik rocks, eow!' |
| writable_buf = array.array('b', b' '*100) |
| fmt = '21s' |
| s = struct.Struct(fmt) |
| |
| # Test without offset |
| s.pack_into(writable_buf, 0, test_string) |
| from_buf = writable_buf.tobytes()[:len(test_string)] |
| self.assertEqual(from_buf, test_string) |
| |
| # Test with offset. |
| s.pack_into(writable_buf, 10, test_string) |
| from_buf = writable_buf.tobytes()[:len(test_string)+10] |
| self.assertEqual(from_buf, test_string[:10] + test_string) |
| |
| # Go beyond boundaries. |
| small_buf = array.array('b', b' '*10) |
| self.assertRaises((ValueError, struct.error), s.pack_into, small_buf, 0, |
| test_string) |
| self.assertRaises((ValueError, struct.error), s.pack_into, small_buf, 2, |
| test_string) |
| |
| # Test bogus offset (issue 3694) |
| sb = small_buf |
| self.assertRaises((TypeError, struct.error), struct.pack_into, b'', sb, |
| None) |
| |
| def test_pack_into_fn(self): |
| test_string = b'Reykjavik rocks, eow!' |
| writable_buf = array.array('b', b' '*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.tobytes()[:len(test_string)] |
| self.assertEqual(from_buf, test_string) |
| |
| # Test with offset. |
| pack_into(writable_buf, 10, test_string) |
| from_buf = writable_buf.tobytes()[:len(test_string)+10] |
| self.assertEqual(from_buf, test_string[:10] + test_string) |
| |
| # Go beyond boundaries. |
| small_buf = array.array('b', b' '*10) |
| self.assertRaises((ValueError, struct.error), pack_into, small_buf, 0, |
| test_string) |
| self.assertRaises((ValueError, struct.error), pack_into, small_buf, 2, |
| test_string) |
| |
| def test_unpack_with_buffer(self): |
| # SF bug 1563759: struct.unpack doesn't support buffer protocol objects |
| data1 = array.array('B', b'\x12\x34\x56\x78') |
| data2 = memoryview(b'\x12\x34\x56\x78') # XXX b'......XXXX......', 6, 4 |
| for data in [data1, data2]: |
| value, = struct.unpack('>I', data) |
| self.assertEqual(value, 0x12345678) |
| |
| def test_bool(self): |
| class ExplodingBool(object): |
| def __bool__(self): |
| raise OSError |
| for prefix in tuple("<>!=")+('',): |
| false = (), [], [], '', 0 |
| true = [1], 'test', 5, -1, 0xffffffff+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) |
| |
| try: |
| struct.pack(prefix + '?', ExplodingBool()) |
| except OSError: |
| pass |
| else: |
| self.fail("Expected OSError: struct.pack(%r, " |
| "ExplodingBool())" % (prefix + '?')) |
| |
| for c in [b'\x01', b'\x7f', b'\xff', b'\x0f', b'\xf0']: |
| self.assertTrue(struct.unpack('>?', c)[0]) |
| |
| 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_trailing_counter(self): |
| store = array.array('b', b' '*100) |
| |
| # format lists containing only count spec should result in an error |
| self.assertRaises(struct.error, struct.pack, '12345') |
| self.assertRaises(struct.error, struct.unpack, '12345', '') |
| self.assertRaises(struct.error, struct.pack_into, '12345', store, 0) |
| self.assertRaises(struct.error, struct.unpack_from, '12345', store, 0) |
| |
| # Format lists with trailing count spec should result in an error |
| self.assertRaises(struct.error, struct.pack, 'c12345', 'x') |
| self.assertRaises(struct.error, struct.unpack, 'c12345', 'x') |
| self.assertRaises(struct.error, struct.pack_into, 'c12345', store, 0, |
| 'x') |
| self.assertRaises(struct.error, struct.unpack_from, 'c12345', store, |
| 0) |
| |
| # Mixed format tests |
| self.assertRaises(struct.error, struct.pack, '14s42', 'spam and eggs') |
| self.assertRaises(struct.error, struct.unpack, '14s42', |
| 'spam and eggs') |
| self.assertRaises(struct.error, struct.pack_into, '14s42', store, 0, |
| 'spam and eggs') |
| self.assertRaises(struct.error, struct.unpack_from, '14s42', store, 0) |
| |
| def test_Struct_reinitialization(self): |
| # Issue 9422: there was a memory leak when reinitializing a |
| # Struct instance. This test can be used to detect the leak |
| # when running with regrtest -L. |
| s = struct.Struct('i') |
| s.__init__('ii') |
| |
| def check_sizeof(self, format_str, number_of_codes): |
| # The size of 'PyStructObject' |
| totalsize = support.calcobjsize('2n3P') |
| # The size taken up by the 'formatcode' dynamic array |
| totalsize += struct.calcsize('P3n0P') * (number_of_codes + 1) |
| support.check_sizeof(self, struct.Struct(format_str), totalsize) |
| |
| @support.cpython_only |
| def test__sizeof__(self): |
| for code in integer_codes: |
| self.check_sizeof(code, 1) |
| self.check_sizeof('BHILfdspP', 9) |
| self.check_sizeof('B' * 1234, 1234) |
| self.check_sizeof('fd', 2) |
| self.check_sizeof('xxxxxxxxxxxxxx', 0) |
| self.check_sizeof('100H', 1) |
| self.check_sizeof('187s', 1) |
| self.check_sizeof('20p', 1) |
| self.check_sizeof('0s', 1) |
| self.check_sizeof('0c', 0) |
| |
| |
| class UnpackIteratorTest(unittest.TestCase): |
| """ |
| Tests for iterative unpacking (struct.Struct.iter_unpack). |
| """ |
| |
| def test_construct(self): |
| def _check_iterator(it): |
| self.assertIsInstance(it, abc.Iterator) |
| self.assertIsInstance(it, abc.Iterable) |
| s = struct.Struct('>ibcp') |
| it = s.iter_unpack(b"") |
| _check_iterator(it) |
| it = s.iter_unpack(b"1234567") |
| _check_iterator(it) |
| # Wrong bytes length |
| with self.assertRaises(struct.error): |
| s.iter_unpack(b"123456") |
| with self.assertRaises(struct.error): |
| s.iter_unpack(b"12345678") |
| # Zero-length struct |
| s = struct.Struct('>') |
| with self.assertRaises(struct.error): |
| s.iter_unpack(b"") |
| with self.assertRaises(struct.error): |
| s.iter_unpack(b"12") |
| |
| def test_iterate(self): |
| s = struct.Struct('>IB') |
| b = bytes(range(1, 16)) |
| it = s.iter_unpack(b) |
| self.assertEqual(next(it), (0x01020304, 5)) |
| self.assertEqual(next(it), (0x06070809, 10)) |
| self.assertEqual(next(it), (0x0b0c0d0e, 15)) |
| self.assertRaises(StopIteration, next, it) |
| self.assertRaises(StopIteration, next, it) |
| |
| def test_arbitrary_buffer(self): |
| s = struct.Struct('>IB') |
| b = bytes(range(1, 11)) |
| it = s.iter_unpack(memoryview(b)) |
| self.assertEqual(next(it), (0x01020304, 5)) |
| self.assertEqual(next(it), (0x06070809, 10)) |
| self.assertRaises(StopIteration, next, it) |
| self.assertRaises(StopIteration, next, it) |
| |
| def test_length_hint(self): |
| lh = operator.length_hint |
| s = struct.Struct('>IB') |
| b = bytes(range(1, 16)) |
| it = s.iter_unpack(b) |
| self.assertEqual(lh(it), 3) |
| next(it) |
| self.assertEqual(lh(it), 2) |
| next(it) |
| self.assertEqual(lh(it), 1) |
| next(it) |
| self.assertEqual(lh(it), 0) |
| self.assertRaises(StopIteration, next, it) |
| self.assertEqual(lh(it), 0) |
| |
| def test_module_func(self): |
| # Sanity check for the global struct.iter_unpack() |
| it = struct.iter_unpack('>IB', bytes(range(1, 11))) |
| self.assertEqual(next(it), (0x01020304, 5)) |
| self.assertEqual(next(it), (0x06070809, 10)) |
| self.assertRaises(StopIteration, next, it) |
| self.assertRaises(StopIteration, next, it) |
| |
| def test_half_float(self): |
| # Little-endian examples from: |
| # http://en.wikipedia.org/wiki/Half_precision_floating-point_format |
| format_bits_float__cleanRoundtrip_list = [ |
| (b'\x00\x3c', 1.0), |
| (b'\x00\xc0', -2.0), |
| (b'\xff\x7b', 65504.0), # (max half precision) |
| (b'\x00\x04', 2**-14), # ~= 6.10352 * 10**-5 (min pos normal) |
| (b'\x01\x00', 2**-24), # ~= 5.96046 * 10**-8 (min pos subnormal) |
| (b'\x00\x00', 0.0), |
| (b'\x00\x80', -0.0), |
| (b'\x00\x7c', float('+inf')), |
| (b'\x00\xfc', float('-inf')), |
| (b'\x55\x35', 0.333251953125), # ~= 1/3 |
| ] |
| |
| for le_bits, f in format_bits_float__cleanRoundtrip_list: |
| be_bits = le_bits[::-1] |
| self.assertEqual(f, struct.unpack('<e', le_bits)[0]) |
| self.assertEqual(le_bits, struct.pack('<e', f)) |
| self.assertEqual(f, struct.unpack('>e', be_bits)[0]) |
| self.assertEqual(be_bits, struct.pack('>e', f)) |
| if sys.byteorder == 'little': |
| self.assertEqual(f, struct.unpack('e', le_bits)[0]) |
| self.assertEqual(le_bits, struct.pack('e', f)) |
| else: |
| self.assertEqual(f, struct.unpack('e', be_bits)[0]) |
| self.assertEqual(be_bits, struct.pack('e', f)) |
| |
| # Check for NaN handling: |
| format_bits__nan_list = [ |
| ('<e', b'\x01\xfc'), |
| ('<e', b'\x00\xfe'), |
| ('<e', b'\xff\xff'), |
| ('<e', b'\x01\x7c'), |
| ('<e', b'\x00\x7e'), |
| ('<e', b'\xff\x7f'), |
| ] |
| |
| for formatcode, bits in format_bits__nan_list: |
| self.assertTrue(math.isnan(struct.unpack('<e', bits)[0])) |
| self.assertTrue(math.isnan(struct.unpack('>e', bits[::-1])[0])) |
| |
| # Check that packing produces a bit pattern representing a quiet NaN: |
| # all exponent bits and the msb of the fraction should all be 1. |
| packed = struct.pack('<e', math.nan) |
| self.assertEqual(packed[1] & 0x7e, 0x7e) |
| packed = struct.pack('<e', -math.nan) |
| self.assertEqual(packed[1] & 0x7e, 0x7e) |
| |
| # Checks for round-to-even behavior |
| format_bits_float__rounding_list = [ |
| ('>e', b'\x00\x01', 2.0**-25 + 2.0**-35), # Rounds to minimum subnormal |
| ('>e', b'\x00\x00', 2.0**-25), # Underflows to zero (nearest even mode) |
| ('>e', b'\x00\x00', 2.0**-26), # Underflows to zero |
| ('>e', b'\x03\xff', 2.0**-14 - 2.0**-24), # Largest subnormal. |
| ('>e', b'\x03\xff', 2.0**-14 - 2.0**-25 - 2.0**-65), |
| ('>e', b'\x04\x00', 2.0**-14 - 2.0**-25), |
| ('>e', b'\x04\x00', 2.0**-14), # Smallest normal. |
| ('>e', b'\x3c\x01', 1.0+2.0**-11 + 2.0**-16), # rounds to 1.0+2**(-10) |
| ('>e', b'\x3c\x00', 1.0+2.0**-11), # rounds to 1.0 (nearest even mode) |
| ('>e', b'\x3c\x00', 1.0+2.0**-12), # rounds to 1.0 |
| ('>e', b'\x7b\xff', 65504), # largest normal |
| ('>e', b'\x7b\xff', 65519), # rounds to 65504 |
| ('>e', b'\x80\x01', -2.0**-25 - 2.0**-35), # Rounds to minimum subnormal |
| ('>e', b'\x80\x00', -2.0**-25), # Underflows to zero (nearest even mode) |
| ('>e', b'\x80\x00', -2.0**-26), # Underflows to zero |
| ('>e', b'\xbc\x01', -1.0-2.0**-11 - 2.0**-16), # rounds to 1.0+2**(-10) |
| ('>e', b'\xbc\x00', -1.0-2.0**-11), # rounds to 1.0 (nearest even mode) |
| ('>e', b'\xbc\x00', -1.0-2.0**-12), # rounds to 1.0 |
| ('>e', b'\xfb\xff', -65519), # rounds to 65504 |
| ] |
| |
| for formatcode, bits, f in format_bits_float__rounding_list: |
| self.assertEqual(bits, struct.pack(formatcode, f)) |
| |
| # This overflows, and so raises an error |
| format_bits_float__roundingError_list = [ |
| # Values that round to infinity. |
| ('>e', 65520.0), |
| ('>e', 65536.0), |
| ('>e', 1e300), |
| ('>e', -65520.0), |
| ('>e', -65536.0), |
| ('>e', -1e300), |
| ('<e', 65520.0), |
| ('<e', 65536.0), |
| ('<e', 1e300), |
| ('<e', -65520.0), |
| ('<e', -65536.0), |
| ('<e', -1e300), |
| ] |
| |
| for formatcode, f in format_bits_float__roundingError_list: |
| self.assertRaises(OverflowError, struct.pack, formatcode, f) |
| |
| # Double rounding |
| format_bits_float__doubleRoundingError_list = [ |
| ('>e', b'\x67\xff', 0x1ffdffffff * 2**-26), # should be 2047, if double-rounded 64>32>16, becomes 2048 |
| ] |
| |
| for formatcode, bits, f in format_bits_float__doubleRoundingError_list: |
| self.assertEqual(bits, struct.pack(formatcode, f)) |
| |
| |
| if __name__ == '__main__': |
| unittest.main() |