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	Avoid immortalizing objects in tests that verify garbage collection of
classes or modules.
This fixes test_ordered_dict and test_struct.
(cherry picked from commit 1b1db2fd9a)
Co-authored-by: Sam Gross <colesbury@gmail.com>
		
	
			
		
			
				
	
	
		
			955 lines
		
	
	
	
		
			39 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			955 lines
		
	
	
	
		
			39 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
from collections import abc
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import array
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import gc
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import math
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import operator
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import unittest
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import struct
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import sys
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import weakref
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from test import support
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from test.support import import_helper, suppress_immortalization
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from test.support.script_helper import assert_python_ok
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ISBIGENDIAN = sys.byteorder == "big"
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integer_codes = 'b', 'B', 'h', 'H', 'i', 'I', 'l', 'L', 'q', 'Q', 'n', 'N'
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byteorders = '', '@', '=', '<', '>', '!'
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def iter_integer_formats(byteorders=byteorders):
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    for code in integer_codes:
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        for byteorder in byteorders:
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            if (byteorder not in ('', '@') and code in ('n', 'N')):
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                continue
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            yield code, byteorder
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def string_reverse(s):
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    return s[::-1]
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def bigendian_to_native(value):
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    if ISBIGENDIAN:
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        return value
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    else:
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        return string_reverse(value)
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class StructTest(unittest.TestCase):
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    def test_isbigendian(self):
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        self.assertEqual((struct.pack('=i', 1)[0] == 0), ISBIGENDIAN)
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    def test_consistence(self):
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        self.assertRaises(struct.error, struct.calcsize, 'Z')
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        sz = struct.calcsize('i')
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        self.assertEqual(sz * 3, struct.calcsize('iii'))
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        fmt = 'cbxxxxxxhhhhiillffd?'
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        fmt3 = '3c3b18x12h6i6l6f3d3?'
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        sz = struct.calcsize(fmt)
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        sz3 = struct.calcsize(fmt3)
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        self.assertEqual(sz * 3, sz3)
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        self.assertRaises(struct.error, struct.pack, 'iii', 3)
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        self.assertRaises(struct.error, struct.pack, 'i', 3, 3, 3)
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        self.assertRaises((TypeError, struct.error), struct.pack, 'i', 'foo')
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        self.assertRaises((TypeError, struct.error), struct.pack, 'P', 'foo')
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        self.assertRaises(struct.error, struct.unpack, 'd', b'flap')
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        s = struct.pack('ii', 1, 2)
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        self.assertRaises(struct.error, struct.unpack, 'iii', s)
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        self.assertRaises(struct.error, struct.unpack, 'i', s)
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    def test_transitiveness(self):
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        c = b'a'
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        b = 1
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        h = 255
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        i = 65535
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        l = 65536
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        f = 3.1415
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        d = 3.1415
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        t = True
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        for prefix in ('', '@', '<', '>', '=', '!'):
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            for format in ('xcbhilfd?', 'xcBHILfd?'):
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                format = prefix + format
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                s = struct.pack(format, c, b, h, i, l, f, d, t)
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                cp, bp, hp, ip, lp, fp, dp, tp = struct.unpack(format, s)
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                self.assertEqual(cp, c)
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                self.assertEqual(bp, b)
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                self.assertEqual(hp, h)
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                self.assertEqual(ip, i)
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                self.assertEqual(lp, l)
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                self.assertEqual(int(100 * fp), int(100 * f))
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                self.assertEqual(int(100 * dp), int(100 * d))
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                self.assertEqual(tp, t)
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    def test_new_features(self):
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        # Test some of the new features in detail
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        # (format, argument, big-endian result, little-endian result, asymmetric)
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        tests = [
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            ('c', b'a', b'a', b'a', 0),
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            ('xc', b'a', b'\0a', b'\0a', 0),
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            ('cx', b'a', b'a\0', b'a\0', 0),
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            ('s', b'a', b'a', b'a', 0),
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            ('0s', b'helloworld', b'', b'', 1),
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            ('1s', b'helloworld', b'h', b'h', 1),
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            ('9s', b'helloworld', b'helloworl', b'helloworl', 1),
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            ('10s', b'helloworld', b'helloworld', b'helloworld', 0),
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            ('11s', b'helloworld', b'helloworld\0', b'helloworld\0', 1),
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            ('20s', b'helloworld', b'helloworld'+10*b'\0', b'helloworld'+10*b'\0', 1),
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            ('b', 7, b'\7', b'\7', 0),
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            ('b', -7, b'\371', b'\371', 0),
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            ('B', 7, b'\7', b'\7', 0),
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            ('B', 249, b'\371', b'\371', 0),
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            ('h', 700, b'\002\274', b'\274\002', 0),
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            ('h', -700, b'\375D', b'D\375', 0),
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            ('H', 700, b'\002\274', b'\274\002', 0),
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            ('H', 0x10000-700, b'\375D', b'D\375', 0),
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            ('i', 70000000, b'\004,\035\200', b'\200\035,\004', 0),
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            ('i', -70000000, b'\373\323\342\200', b'\200\342\323\373', 0),
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            ('I', 70000000, b'\004,\035\200', b'\200\035,\004', 0),
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            ('I', 0x100000000-70000000, b'\373\323\342\200', b'\200\342\323\373', 0),
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            ('l', 70000000, b'\004,\035\200', b'\200\035,\004', 0),
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            ('l', -70000000, b'\373\323\342\200', b'\200\342\323\373', 0),
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            ('L', 70000000, b'\004,\035\200', b'\200\035,\004', 0),
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            ('L', 0x100000000-70000000, b'\373\323\342\200', b'\200\342\323\373', 0),
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            ('f', 2.0, b'@\000\000\000', b'\000\000\000@', 0),
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            ('d', 2.0, b'@\000\000\000\000\000\000\000',
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                       b'\000\000\000\000\000\000\000@', 0),
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            ('f', -2.0, b'\300\000\000\000', b'\000\000\000\300', 0),
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            ('d', -2.0, b'\300\000\000\000\000\000\000\000',
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                        b'\000\000\000\000\000\000\000\300', 0),
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            ('?', 0, b'\0', b'\0', 0),
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            ('?', 3, b'\1', b'\1', 1),
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            ('?', True, b'\1', b'\1', 0),
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            ('?', [], b'\0', b'\0', 1),
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            ('?', (1,), b'\1', b'\1', 1),
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        ]
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        for fmt, arg, big, lil, asy in tests:
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            for (xfmt, exp) in [('>'+fmt, big), ('!'+fmt, big), ('<'+fmt, lil),
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                                ('='+fmt, ISBIGENDIAN and big or lil)]:
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                res = struct.pack(xfmt, arg)
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                self.assertEqual(res, exp)
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                self.assertEqual(struct.calcsize(xfmt), len(res))
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                rev = struct.unpack(xfmt, res)[0]
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                if rev != arg:
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                    self.assertTrue(asy)
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    def test_calcsize(self):
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        expected_size = {
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            'b': 1, 'B': 1,
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            'h': 2, 'H': 2,
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            'i': 4, 'I': 4,
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            'l': 4, 'L': 4,
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            'q': 8, 'Q': 8,
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            }
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        # standard integer sizes
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        for code, byteorder in iter_integer_formats(('=', '<', '>', '!')):
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            format = byteorder+code
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            size = struct.calcsize(format)
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            self.assertEqual(size, expected_size[code])
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        # native integer sizes
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        native_pairs = 'bB', 'hH', 'iI', 'lL', 'nN', 'qQ'
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        for format_pair in native_pairs:
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            for byteorder in '', '@':
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                signed_size = struct.calcsize(byteorder + format_pair[0])
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                unsigned_size = struct.calcsize(byteorder + format_pair[1])
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                self.assertEqual(signed_size, unsigned_size)
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        # bounds for native integer sizes
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        self.assertEqual(struct.calcsize('b'), 1)
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        self.assertLessEqual(2, struct.calcsize('h'))
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        self.assertLessEqual(4, struct.calcsize('l'))
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        self.assertLessEqual(struct.calcsize('h'), struct.calcsize('i'))
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        self.assertLessEqual(struct.calcsize('i'), struct.calcsize('l'))
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        self.assertLessEqual(8, struct.calcsize('q'))
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        self.assertLessEqual(struct.calcsize('l'), struct.calcsize('q'))
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        self.assertGreaterEqual(struct.calcsize('n'), struct.calcsize('i'))
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        self.assertGreaterEqual(struct.calcsize('n'), struct.calcsize('P'))
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    def test_integers(self):
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        # Integer tests (bBhHiIlLqQnN).
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        import binascii
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        class IntTester(unittest.TestCase):
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            def __init__(self, format):
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                super(IntTester, self).__init__(methodName='test_one')
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                self.format = format
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                self.code = format[-1]
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                self.byteorder = format[:-1]
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                if not self.byteorder in byteorders:
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                    raise ValueError("unrecognized packing byteorder: %s" %
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                                     self.byteorder)
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                self.bytesize = struct.calcsize(format)
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                self.bitsize = self.bytesize * 8
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                if self.code in tuple('bhilqn'):
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                    self.signed = True
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                    self.min_value = -(2**(self.bitsize-1))
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                    self.max_value = 2**(self.bitsize-1) - 1
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                elif self.code in tuple('BHILQN'):
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                    self.signed = False
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                    self.min_value = 0
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                    self.max_value = 2**self.bitsize - 1
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                else:
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                    raise ValueError("unrecognized format code: %s" %
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                                     self.code)
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            def test_one(self, x, pack=struct.pack,
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                                  unpack=struct.unpack,
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                                  unhexlify=binascii.unhexlify):
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                format = self.format
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                if self.min_value <= x <= self.max_value:
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                    expected = x
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                    if self.signed and x < 0:
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                        expected += 1 << self.bitsize
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                    self.assertGreaterEqual(expected, 0)
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                    expected = '%x' % expected
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                    if len(expected) & 1:
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                        expected = "0" + expected
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                    expected = expected.encode('ascii')
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                    expected = unhexlify(expected)
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                    expected = (b"\x00" * (self.bytesize - len(expected)) +
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                                expected)
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                    if (self.byteorder == '<' or
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                        self.byteorder in ('', '@', '=') and not ISBIGENDIAN):
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                        expected = string_reverse(expected)
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                    self.assertEqual(len(expected), self.bytesize)
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                    # Pack work?
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                    got = pack(format, x)
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                    self.assertEqual(got, expected)
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                    # Unpack work?
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                    retrieved = unpack(format, got)[0]
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                    self.assertEqual(x, retrieved)
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                    # Adding any byte should cause a "too big" error.
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                    self.assertRaises((struct.error, TypeError), unpack, format,
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                                                                 b'\x01' + got)
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                else:
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                    # x is out of range -- verify pack realizes that.
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                    self.assertRaises((OverflowError, ValueError, struct.error),
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                                      pack, format, x)
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            def run(self):
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                from random import randrange
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                # Create all interesting powers of 2.
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                values = []
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                for exp in range(self.bitsize + 3):
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                    values.append(1 << exp)
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                # Add some random values.
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                for i in range(self.bitsize):
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                    val = 0
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                    for j in range(self.bytesize):
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                        val = (val << 8) | randrange(256)
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                    values.append(val)
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                # Values absorbed from other tests
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                values.extend([300, 700000, sys.maxsize*4])
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                # Try all those, and their negations, and +-1 from
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                # them.  Note that this tests all power-of-2
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                # boundaries in range, and a few out of range, plus
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                # +-(2**n +- 1).
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                for base in values:
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                    for val in -base, base:
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                        for incr in -1, 0, 1:
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                            x = val + incr
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                            self.test_one(x)
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                # Some error cases.
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                class NotAnInt:
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                    def __int__(self):
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                        return 42
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                # Objects with an '__index__' method should be allowed
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                # to pack as integers.  That is assuming the implemented
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                # '__index__' method returns an 'int'.
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                class Indexable(object):
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                    def __init__(self, value):
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                        self._value = value
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                    def __index__(self):
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                        return self._value
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                # If the '__index__' method raises a type error, then
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                # '__int__' should be used with a deprecation warning.
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                class BadIndex(object):
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                    def __index__(self):
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                        raise TypeError
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                    def __int__(self):
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                        return 42
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                self.assertRaises((TypeError, struct.error),
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                                  struct.pack, self.format,
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                                  "a string")
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                self.assertRaises((TypeError, struct.error),
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                                  struct.pack, self.format,
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                                  randrange)
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                self.assertRaises((TypeError, struct.error),
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                                  struct.pack, self.format,
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                                  3+42j)
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                self.assertRaises((TypeError, struct.error),
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                                  struct.pack, self.format,
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                                  NotAnInt())
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                self.assertRaises((TypeError, struct.error),
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                                  struct.pack, self.format,
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                                  BadIndex())
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                # Check for legitimate values from '__index__'.
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                for obj in (Indexable(0), Indexable(10), Indexable(17),
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                            Indexable(42), Indexable(100), Indexable(127)):
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                    try:
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                        struct.pack(format, obj)
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                    except:
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                        self.fail("integer code pack failed on object "
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                                  "with '__index__' method")
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                # Check for bogus values from '__index__'.
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                for obj in (Indexable(b'a'), Indexable('b'), Indexable(None),
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                            Indexable({'a': 1}), Indexable([1, 2, 3])):
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                    self.assertRaises((TypeError, struct.error),
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                                      struct.pack, self.format,
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                                      obj)
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        for code, byteorder in iter_integer_formats():
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            format = byteorder+code
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            t = IntTester(format)
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            t.run()
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    def test_nN_code(self):
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        # n and N don't exist in standard sizes
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        def assertStructError(func, *args, **kwargs):
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            with self.assertRaises(struct.error) as cm:
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                func(*args, **kwargs)
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            self.assertIn("bad char in struct format", str(cm.exception))
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        for code in 'nN':
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            for byteorder in ('=', '<', '>', '!'):
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                format = byteorder+code
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                assertStructError(struct.calcsize, format)
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                assertStructError(struct.pack, format, 0)
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                assertStructError(struct.unpack, format, b"")
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    def test_p_code(self):
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        # Test p ("Pascal string") code.
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        for code, input, expected, expectedback in [
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                ('p',  b'abc', b'\x00',            b''),
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                ('1p', b'abc', b'\x00',            b''),
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                ('2p', b'abc', b'\x01a',           b'a'),
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                ('3p', b'abc', b'\x02ab',          b'ab'),
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                ('4p', b'abc', b'\x03abc',         b'abc'),
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                ('5p', b'abc', b'\x03abc\x00',     b'abc'),
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                ('6p', b'abc', b'\x03abc\x00\x00', b'abc'),
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                ('1000p', b'x'*1000, b'\xff' + b'x'*999, b'x'*255)]:
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            got = struct.pack(code, input)
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            self.assertEqual(got, expected)
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            (got,) = struct.unpack(code, got)
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            self.assertEqual(got, expectedback)
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    def test_705836(self):
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        # SF bug 705836.  "<f" and ">f" had a severe rounding bug, where a carry
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        # from the low-order discarded bits could propagate into the exponent
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        # field, causing the result to be wrong by a factor of 2.
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        for base in range(1, 33):
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            # smaller <- largest representable float less than base.
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            delta = 0.5
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            while base - delta / 2.0 != base:
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                delta /= 2.0
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            smaller = base - delta
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            # Packing this rounds away a solid string of trailing 1 bits.
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            packed = struct.pack("<f", smaller)
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            unpacked = struct.unpack("<f", packed)[0]
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            # This failed at base = 2, 4, and 32, with unpacked = 1, 2, and
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            # 16, respectively.
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            self.assertEqual(base, unpacked)
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            bigpacked = struct.pack(">f", smaller)
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            self.assertEqual(bigpacked, string_reverse(packed))
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            unpacked = struct.unpack(">f", bigpacked)[0]
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            self.assertEqual(base, unpacked)
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        # Largest finite IEEE single.
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        big = (1 << 24) - 1
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        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', b'')
 | 
						|
        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', b'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',
 | 
						|
                          b'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)
 | 
						|
 | 
						|
    def test_boundary_error_message(self):
 | 
						|
        regex1 = (
 | 
						|
            r'pack_into requires a buffer of at least 6 '
 | 
						|
            r'bytes for packing 1 bytes at offset 5 '
 | 
						|
            r'\(actual buffer size is 1\)'
 | 
						|
        )
 | 
						|
        with self.assertRaisesRegex(struct.error, regex1):
 | 
						|
            struct.pack_into('b', bytearray(1), 5, 1)
 | 
						|
 | 
						|
        regex2 = (
 | 
						|
            r'unpack_from requires a buffer of at least 6 '
 | 
						|
            r'bytes for unpacking 1 bytes at offset 5 '
 | 
						|
            r'\(actual buffer size is 1\)'
 | 
						|
        )
 | 
						|
        with self.assertRaisesRegex(struct.error, regex2):
 | 
						|
            struct.unpack_from('b', bytearray(1), 5)
 | 
						|
 | 
						|
    def test_boundary_error_message_with_negative_offset(self):
 | 
						|
        byte_list = bytearray(10)
 | 
						|
        with self.assertRaisesRegex(
 | 
						|
                struct.error,
 | 
						|
                r'no space to pack 4 bytes at offset -2'):
 | 
						|
            struct.pack_into('<I', byte_list, -2, 123)
 | 
						|
 | 
						|
        with self.assertRaisesRegex(
 | 
						|
                struct.error,
 | 
						|
                'offset -11 out of range for 10-byte buffer'):
 | 
						|
            struct.pack_into('<B', byte_list, -11, 123)
 | 
						|
 | 
						|
        with self.assertRaisesRegex(
 | 
						|
                struct.error,
 | 
						|
                r'not enough data to unpack 4 bytes at offset -2'):
 | 
						|
            struct.unpack_from('<I', byte_list, -2)
 | 
						|
 | 
						|
        with self.assertRaisesRegex(
 | 
						|
                struct.error,
 | 
						|
                "offset -11 out of range for 10-byte buffer"):
 | 
						|
            struct.unpack_from('<B', byte_list, -11)
 | 
						|
 | 
						|
    def test_boundary_error_message_with_large_offset(self):
 | 
						|
        # Test overflows cause by large offset and value size (issue 30245)
 | 
						|
        regex1 = (
 | 
						|
            r'pack_into requires a buffer of at least ' + str(sys.maxsize + 4) +
 | 
						|
            r' bytes for packing 4 bytes at offset ' + str(sys.maxsize) +
 | 
						|
            r' \(actual buffer size is 10\)'
 | 
						|
        )
 | 
						|
        with self.assertRaisesRegex(struct.error, regex1):
 | 
						|
            struct.pack_into('<I', bytearray(10), sys.maxsize, 1)
 | 
						|
 | 
						|
        regex2 = (
 | 
						|
            r'unpack_from requires a buffer of at least ' + str(sys.maxsize + 4) +
 | 
						|
            r' bytes for unpacking 4 bytes at offset ' + str(sys.maxsize) +
 | 
						|
            r' \(actual buffer size is 10\)'
 | 
						|
        )
 | 
						|
        with self.assertRaisesRegex(struct.error, regex2):
 | 
						|
            struct.unpack_from('<I', bytearray(10), sys.maxsize)
 | 
						|
 | 
						|
    def test_issue29802(self):
 | 
						|
        # When the second argument of struct.unpack() was of wrong type
 | 
						|
        # the Struct object was decrefed twice and the reference to
 | 
						|
        # deallocated object was left in a cache.
 | 
						|
        with self.assertRaises(TypeError):
 | 
						|
            struct.unpack('b', 0)
 | 
						|
        # Shouldn't crash.
 | 
						|
        self.assertEqual(struct.unpack('b', b'a'), (b'a'[0],))
 | 
						|
 | 
						|
    def test_format_attr(self):
 | 
						|
        s = struct.Struct('=i2H')
 | 
						|
        self.assertEqual(s.format, '=i2H')
 | 
						|
 | 
						|
        # use a bytes string
 | 
						|
        s2 = struct.Struct(s.format.encode())
 | 
						|
        self.assertEqual(s2.format, s.format)
 | 
						|
 | 
						|
    def test_struct_cleans_up_at_runtime_shutdown(self):
 | 
						|
        code = """if 1:
 | 
						|
            import struct
 | 
						|
 | 
						|
            class C:
 | 
						|
                def __init__(self):
 | 
						|
                    self.pack = struct.pack
 | 
						|
                def __del__(self):
 | 
						|
                    self.pack('I', -42)
 | 
						|
 | 
						|
            struct.x = C()
 | 
						|
            """
 | 
						|
        rc, stdout, stderr = assert_python_ok("-c", code)
 | 
						|
        self.assertEqual(rc, 0)
 | 
						|
        self.assertEqual(stdout.rstrip(), b"")
 | 
						|
        self.assertIn(b"Exception ignored in:", stderr)
 | 
						|
        self.assertIn(b"C.__del__", stderr)
 | 
						|
 | 
						|
    @suppress_immortalization()
 | 
						|
    def test__struct_reference_cycle_cleaned_up(self):
 | 
						|
        # Regression test for python/cpython#94207.
 | 
						|
 | 
						|
        # When we create a new struct module, trigger use of its cache,
 | 
						|
        # and then delete it ...
 | 
						|
        _struct_module = import_helper.import_fresh_module("_struct")
 | 
						|
        module_ref = weakref.ref(_struct_module)
 | 
						|
        _struct_module.calcsize("b")
 | 
						|
        del _struct_module
 | 
						|
 | 
						|
        # Then the module should have been garbage collected.
 | 
						|
        gc.collect()
 | 
						|
        self.assertIsNone(
 | 
						|
            module_ref(), "_struct module was not garbage collected")
 | 
						|
 | 
						|
    @support.cpython_only
 | 
						|
    def test__struct_types_immutable(self):
 | 
						|
        # See https://github.com/python/cpython/issues/94254
 | 
						|
 | 
						|
        Struct = struct.Struct
 | 
						|
        unpack_iterator = type(struct.iter_unpack("b", b'x'))
 | 
						|
        for cls in (Struct, unpack_iterator):
 | 
						|
            with self.subTest(cls=cls):
 | 
						|
                with self.assertRaises(TypeError):
 | 
						|
                    cls.x = 1
 | 
						|
 | 
						|
 | 
						|
    def test_issue35714(self):
 | 
						|
        # Embedded null characters should not be allowed in format strings.
 | 
						|
        for s in '\0', '2\0i', b'\0':
 | 
						|
            with self.assertRaisesRegex(struct.error,
 | 
						|
                                        'embedded null character'):
 | 
						|
                struct.calcsize(s)
 | 
						|
 | 
						|
    @support.cpython_only
 | 
						|
    def test_issue98248(self):
 | 
						|
        def test_error_msg(prefix, int_type, is_unsigned):
 | 
						|
            fmt_str = prefix + int_type
 | 
						|
            size = struct.calcsize(fmt_str)
 | 
						|
            if is_unsigned:
 | 
						|
                max_ = 2 ** (size * 8) - 1
 | 
						|
                min_ = 0
 | 
						|
            else:
 | 
						|
                max_ = 2 ** (size * 8 - 1) - 1
 | 
						|
                min_ = -2 ** (size * 8 - 1)
 | 
						|
            error_msg = f"'{int_type}' format requires {min_} <= number <= {max_}"
 | 
						|
            for number in [int(-1e50), min_ - 1, max_ + 1, int(1e50)]:
 | 
						|
                with self.subTest(format_str=fmt_str, number=number):
 | 
						|
                    with self.assertRaisesRegex(struct.error, error_msg):
 | 
						|
                        struct.pack(fmt_str, number)
 | 
						|
            error_msg = "required argument is not an integer"
 | 
						|
            not_number = ""
 | 
						|
            with self.subTest(format_str=fmt_str, number=not_number):
 | 
						|
                with self.assertRaisesRegex(struct.error, error_msg):
 | 
						|
                    struct.pack(fmt_str, not_number)
 | 
						|
 | 
						|
        for prefix in '@=<>':
 | 
						|
            for int_type in 'BHILQ':
 | 
						|
                test_error_msg(prefix, int_type, True)
 | 
						|
            for int_type in 'bhilq':
 | 
						|
                test_error_msg(prefix, int_type, False)
 | 
						|
 | 
						|
        int_type = 'N'
 | 
						|
        test_error_msg('@', int_type, True)
 | 
						|
 | 
						|
        int_type = 'n'
 | 
						|
        test_error_msg('@', int_type, False)
 | 
						|
 | 
						|
    @support.cpython_only
 | 
						|
    def test_issue98248_error_propagation(self):
 | 
						|
        class Div0:
 | 
						|
            def __index__(self):
 | 
						|
                1 / 0
 | 
						|
 | 
						|
        def test_error_propagation(fmt_str):
 | 
						|
            with self.subTest(format_str=fmt_str, exception="ZeroDivisionError"):
 | 
						|
                with self.assertRaises(ZeroDivisionError):
 | 
						|
                    struct.pack(fmt_str, Div0())
 | 
						|
 | 
						|
        for prefix in '@=<>':
 | 
						|
            for int_type in 'BHILQbhilq':
 | 
						|
                test_error_propagation(prefix + int_type)
 | 
						|
 | 
						|
        test_error_propagation('N')
 | 
						|
        test_error_propagation('n')
 | 
						|
 | 
						|
    def test_struct_subclass_instantiation(self):
 | 
						|
        # Regression test for https://github.com/python/cpython/issues/112358
 | 
						|
        class MyStruct(struct.Struct):
 | 
						|
            def __init__(self):
 | 
						|
                super().__init__('>h')
 | 
						|
 | 
						|
        my_struct = MyStruct()
 | 
						|
        self.assertEqual(my_struct.pack(12345), b'\x30\x39')
 | 
						|
 | 
						|
    def test_repr(self):
 | 
						|
        s = struct.Struct('=i2H')
 | 
						|
        self.assertEqual(repr(s), f'Struct({s.format!r})')
 | 
						|
 | 
						|
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_uninstantiable(self):
 | 
						|
        iter_unpack_type = type(struct.Struct(">ibcp").iter_unpack(b""))
 | 
						|
        self.assertRaises(TypeError, iter_unpack_type)
 | 
						|
 | 
						|
    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()
 |