| import array |
| import unittest |
| import struct |
| import warnings |
| |
| from functools import wraps |
| from test.support import TestFailed, verbose, run_unittest |
| |
| import sys |
| ISBIGENDIAN = sys.byteorder == "big" |
| IS32BIT = sys.maxsize == 0x7fffffff |
| del sys |
| |
| try: |
| import _struct |
| except ImportError: |
| PY_STRUCT_FLOAT_COERCE = 2 |
| else: |
| PY_STRUCT_FLOAT_COERCE = getattr(_struct, '_PY_STRUCT_FLOAT_COERCE', 0) |
| |
| def string_reverse(s): |
| return s[::-1] |
| |
| 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 |
| |
| 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 |
| 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] == 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', 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', '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', 70000000, '\004,\035\200', '\200\035,\004', 0), |
| ('I', 0x100000000-70000000, '\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', 70000000, '\004,\035\200', '\200\035,\004', 0), |
| ('L', 0x100000000-70000000, '\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: |
| big = bytes(big, "latin-1") |
| lil = bytes(lil, "latin-1") |
| 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 isinstance(arg, str): |
| # Strings are returned as bytes since you can't know the |
| # encoding of the string when packed. |
| arg = bytes(arg, 'latin1') |
| if rev != arg: |
| self.assert_(asy) |
| |
| def test_native_qQ(self): |
| # can't pack -1 as unsigned regardless |
| self.assertRaises((struct.error, OverflowError), 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: |
| nbytes = 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' * nbytes), |
| ('q', 0, '\x00' * nbytes), |
| ('Q', 0, '\x00' * nbytes), |
| ('q', 1, '\x00' * (nbytes-1) + '\x01'), |
| ('Q', (1 << (8*nbytes))-1, '\xff' * nbytes), |
| ('q', (1 << (8*nbytes-1))-1, '\x7f' + '\xff' * (nbytes - 1))): |
| expected = bytes(expected, "latin-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): |
| |
| 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 = 2**self.bitsize - 1 |
| self.signed_min = -(2**(self.bitsize-1)) |
| self.signed_max = 2**(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 = x |
| if x < 0: |
| expected += 1 << self.bitsize |
| self.assert_(expected > 0) |
| expected = hex(expected)[2:] # chop "0x" |
| if len(expected) & 1: |
| expected = "0" + expected |
| expected = unhexlify(expected) |
| expected = b"\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, b'\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, b'\x01' + got) |
| |
| else: |
| # x is out of range -- verify pack realizes that. |
| self.assertRaises((struct.error, OverflowError), |
| pack, ">" + code, x) |
| self.assertRaises((struct.error, OverflowError), |
| 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 = x |
| expected = hex(expected)[2:] # chop "0x" |
| if len(expected) & 1: |
| expected = "0" + expected |
| expected = unhexlify(expected) |
| expected = b"\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, b'\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, b'\x01' + got) |
| |
| else: |
| # x is out of range -- verify pack realizes that. |
| self.assertRaises((struct.error, OverflowError), |
| pack, ">" + code, x) |
| self.assertRaises((struct.error, OverflowError), |
| 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(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) |
| |
| # 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', b''), |
| ('1p', 'abc', '\x00', b''), |
| ('2p', 'abc', '\x01a', b'a'), |
| ('3p', 'abc', '\x02ab', b'ab'), |
| ('4p', 'abc', '\x03abc', b'abc'), |
| ('5p', 'abc', '\x03abc\x00', b'abc'), |
| ('6p', 'abc', '\x03abc\x00\x00', b'abc'), |
| ('1000p', 'x'*1000, '\xff' + 'x'*999, b'x'*255)]: |
| expected = bytes(expected, "latin-1") |
| 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_1229380(self): |
| # SF bug 1229380. No struct.pack exception for some out of |
| # range integers |
| import sys |
| for endian in ('', '>', '<'): |
| for fmt in ('B', 'H', 'I', 'L'): |
| self.assertRaises((struct.error, OverflowError), struct.pack, |
| endian + fmt, -1) |
| |
| self.assertRaises((struct.error, OverflowError), struct.pack, |
| endian + 'B', 300) |
| self.assertRaises((struct.error, OverflowError), struct.pack, |
| endian + 'H', 70000) |
| |
| self.assertRaises((struct.error, OverflowError), struct.pack, |
| endian + 'I', sys.maxsize * 4) |
| self.assertRaises((struct.error, OverflowError), struct.pack, |
| endian + 'L', sys.maxsize * 4) |
| |
| 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_unpack_from(self): |
| test_string = b'abcd01234' |
| fmt = '4s' |
| s = struct.Struct(fmt) |
| for cls in (bytes, bytearray): |
| data = cls(test_string) |
| if not isinstance(data, (bytes, bytearray)): |
| bytes_data = bytes(data, 'latin1') |
| else: |
| bytes_data = data |
| 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), (bytes_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) |
| |
| 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.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('b', b' '*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 = 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.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('b', b' '*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): |
| # SF bug 1563759: struct.unpack doens'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): |
| 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) |
| |
| for c in [b'\x01', b'\x7f', b'\xff', b'\x0f', b'\xf0']: |
| self.assertTrue(struct.unpack('>?', c)[0]) |
| |
| if IS32BIT: |
| def test_crasher(self): |
| self.assertRaises(MemoryError, struct.pack, "357913941b", "a") |
| |
| |
| def test_main(): |
| run_unittest(StructTest) |
| |
| if __name__ == '__main__': |
| test_main() |