import collections
import copyreg
import dbm
import io
import functools
import struct
import sys
import unittest
import weakref
from http.cookies import SimpleCookie

from test import support
from test.support import (
    TestFailed, TESTFN, run_with_locale, no_tracing,
    _2G, _4G, bigmemtest,
    )

import pickle5 as pickle
from pickle5 import pickletools, bytes_types

requires_32b = unittest.skipUnless(sys.maxsize < 2**32,
                                   "test is only meaningful on 32-bit builds")

# Tests that try a number of pickle protocols should have a
#     for proto in protocols:
# kind of outer loop.
protocols = range(pickle.HIGHEST_PROTOCOL + 1)


# Return True if opcode code appears in the pickle, else False.
def opcode_in_pickle(code, pickle):
    for op, dummy, dummy in pickletools.genops(pickle):
        if op.code == code.decode("latin-1"):
            return True
    return False

# Return the number of times opcode code appears in pickle.
def count_opcode(code, pickle):
    n = 0
    for op, dummy, dummy in pickletools.genops(pickle):
        if op.code == code.decode("latin-1"):
            n += 1
    return n


class UnseekableIO(io.BytesIO):
    def peek(self, *args):
        raise NotImplementedError

    def seekable(self):
        return False

    def seek(self, *args):
        raise io.UnsupportedOperation

    def tell(self):
        raise io.UnsupportedOperation


class TrivialReadableIO:
    """
    A readable file object that doesn't support readinto().
    """
    def __init__(self, *args, **kwargs):
        self._bio = io.BytesIO(*args, **kwargs)

    def read(self, n):
        return self._bio.read(n)

    def readline(self, n=None):
        return self._bio.readline(n)

    def getvalue(self):
        return self._bio.getvalue()


# We can't very well test the extension registry without putting known stuff
# in it, but we have to be careful to restore its original state.  Code
# should do this:
#
#     e = ExtensionSaver(extension_code)
#     try:
#         fiddle w/ the extension registry's stuff for extension_code
#     finally:
#         e.restore()

class ExtensionSaver:
    # Remember current registration for code (if any), and remove it (if
    # there is one).
    def __init__(self, code):
        self.code = code
        if code in copyreg._inverted_registry:
            self.pair = copyreg._inverted_registry[code]
            copyreg.remove_extension(self.pair[0], self.pair[1], code)
        else:
            self.pair = None

    # Restore previous registration for code.
    def restore(self):
        code = self.code
        curpair = copyreg._inverted_registry.get(code)
        if curpair is not None:
            copyreg.remove_extension(curpair[0], curpair[1], code)
        pair = self.pair
        if pair is not None:
            copyreg.add_extension(pair[0], pair[1], code)

class C:
    def __eq__(self, other):
        return self.__dict__ == other.__dict__

class D(C):
    def __init__(self, arg):
        pass

class E(C):
    def __getinitargs__(self):
        return ()

class H(object):
    pass

# Hashable mutable key
class K(object):
    def __init__(self, value):
        self.value = value

    def __reduce__(self):
        # Shouldn't support the recursion itself
        return K, (self.value,)

import __main__
__main__.C = C
C.__module__ = "__main__"
__main__.D = D
D.__module__ = "__main__"
__main__.E = E
E.__module__ = "__main__"
__main__.H = H
H.__module__ = "__main__"
__main__.K = K
K.__module__ = "__main__"

class myint(int):
    def __init__(self, x):
        self.str = str(x)

class initarg(C):

    def __init__(self, a, b):
        self.a = a
        self.b = b

    def __getinitargs__(self):
        return self.a, self.b

class metaclass(type):
    pass

class use_metaclass(object, metaclass=metaclass):
    pass

class pickling_metaclass(type):
    def __eq__(self, other):
        return (type(self) == type(other) and
                self.reduce_args == other.reduce_args)

    def __reduce__(self):
        return (create_dynamic_class, self.reduce_args)

def create_dynamic_class(name, bases):
    result = pickling_metaclass(name, bases, dict())
    result.reduce_args = (name, bases)
    return result


class ZeroCopyBytes(bytes):

    def __reduce_ex__(self, protocol):
        if protocol >= 5:
            return type(self)._reconstruct, (pickle.PickleBuffer(self),), None
        else:
            return type(self)._reconstruct, (bytes(self),)

    def __repr__(self):
        return "{}({!r})".format(self.__class__.__name__, bytes(self))

    __str__ = __repr__

    @classmethod
    def _reconstruct(cls, obj):
        with memoryview(obj) as m:
            obj = m.obj
            if type(obj) is cls:
                # Zero-copy
                return obj
            else:
                return cls(obj)


class ZeroCopyBytearray(bytearray):

    def __reduce_ex__(self, protocol):
        if protocol >= 5:
            return type(self)._reconstruct, (pickle.PickleBuffer(self),), None
        else:
            return type(self)._reconstruct, (bytes(self),)

    def __repr__(self):
        return "{}({!r})".format(self.__class__.__name__, bytes(self))

    __str__ = __repr__

    @classmethod
    def _reconstruct(cls, obj):
        with memoryview(obj) as m:
            obj = m.obj
            if type(obj) is cls:
                # Zero-copy
                return obj
            else:
                return cls(obj)


# DATA0 .. DATA4 are the pickles we expect under the various protocols, for
# the object returned by create_data().

DATA0 = (
    b'(lp0\nL0L\naL1L\naF2.0\n'
    b'ac__builtin__\ncomple'
    b'x\np1\n(F3.0\nF0.0\ntp2\n'
    b'Rp3\naL1L\naL-1L\naL255'
    b'L\naL-255L\naL-256L\naL'
    b'65535L\naL-65535L\naL-'
    b'65536L\naL2147483647L'
    b'\naL-2147483647L\naL-2'
    b'147483648L\na(Vabc\np4'
    b'\ng4\nccopy_reg\n_recon'
    b'structor\np5\n(c__main'
    b'__\nC\np6\nc__builtin__'
    b'\nobject\np7\nNtp8\nRp9\n'
    b'(dp10\nVfoo\np11\nL1L\ns'
    b'Vbar\np12\nL2L\nsbg9\ntp'
    b'13\nag13\naL5L\na.'
)

# Disassembly of DATA0
DATA0_DIS = """\
    0: (    MARK
    1: l        LIST       (MARK at 0)
    2: p    PUT        0
    5: L    LONG       0
    9: a    APPEND
   10: L    LONG       1
   14: a    APPEND
   15: F    FLOAT      2.0
   20: a    APPEND
   21: c    GLOBAL     '__builtin__ complex'
   42: p    PUT        1
   45: (    MARK
   46: F        FLOAT      3.0
   51: F        FLOAT      0.0
   56: t        TUPLE      (MARK at 45)
   57: p    PUT        2
   60: R    REDUCE
   61: p    PUT        3
   64: a    APPEND
   65: L    LONG       1
   69: a    APPEND
   70: L    LONG       -1
   75: a    APPEND
   76: L    LONG       255
   82: a    APPEND
   83: L    LONG       -255
   90: a    APPEND
   91: L    LONG       -256
   98: a    APPEND
   99: L    LONG       65535
  107: a    APPEND
  108: L    LONG       -65535
  117: a    APPEND
  118: L    LONG       -65536
  127: a    APPEND
  128: L    LONG       2147483647
  141: a    APPEND
  142: L    LONG       -2147483647
  156: a    APPEND
  157: L    LONG       -2147483648
  171: a    APPEND
  172: (    MARK
  173: V        UNICODE    'abc'
  178: p        PUT        4
  181: g        GET        4
  184: c        GLOBAL     'copy_reg _reconstructor'
  209: p        PUT        5
  212: (        MARK
  213: c            GLOBAL     '__main__ C'
  225: p            PUT        6
  228: c            GLOBAL     '__builtin__ object'
  248: p            PUT        7
  251: N            NONE
  252: t            TUPLE      (MARK at 212)
  253: p        PUT        8
  256: R        REDUCE
  257: p        PUT        9
  260: (        MARK
  261: d            DICT       (MARK at 260)
  262: p        PUT        10
  266: V        UNICODE    'foo'
  271: p        PUT        11
  275: L        LONG       1
  279: s        SETITEM
  280: V        UNICODE    'bar'
  285: p        PUT        12
  289: L        LONG       2
  293: s        SETITEM
  294: b        BUILD
  295: g        GET        9
  298: t        TUPLE      (MARK at 172)
  299: p    PUT        13
  303: a    APPEND
  304: g    GET        13
  308: a    APPEND
  309: L    LONG       5
  313: a    APPEND
  314: .    STOP
highest protocol among opcodes = 0
"""

DATA1 = (
    b']q\x00(K\x00K\x01G@\x00\x00\x00\x00\x00\x00\x00c__'
    b'builtin__\ncomplex\nq\x01'
    b'(G@\x08\x00\x00\x00\x00\x00\x00G\x00\x00\x00\x00\x00\x00\x00\x00t'
    b'q\x02Rq\x03K\x01J\xff\xff\xff\xffK\xffJ\x01\xff\xff\xffJ'
    b'\x00\xff\xff\xffM\xff\xffJ\x01\x00\xff\xffJ\x00\x00\xff\xffJ\xff\xff'
    b'\xff\x7fJ\x01\x00\x00\x80J\x00\x00\x00\x80(X\x03\x00\x00\x00ab'
    b'cq\x04h\x04ccopy_reg\n_reco'
    b'nstructor\nq\x05(c__main'
    b'__\nC\nq\x06c__builtin__\n'
    b'object\nq\x07Ntq\x08Rq\t}q\n('
    b'X\x03\x00\x00\x00fooq\x0bK\x01X\x03\x00\x00\x00bar'
    b'q\x0cK\x02ubh\ttq\rh\rK\x05e.'
)

# Disassembly of DATA1
DATA1_DIS = """\
    0: ]    EMPTY_LIST
    1: q    BINPUT     0
    3: (    MARK
    4: K        BININT1    0
    6: K        BININT1    1
    8: G        BINFLOAT   2.0
   17: c        GLOBAL     '__builtin__ complex'
   38: q        BINPUT     1
   40: (        MARK
   41: G            BINFLOAT   3.0
   50: G            BINFLOAT   0.0
   59: t            TUPLE      (MARK at 40)
   60: q        BINPUT     2
   62: R        REDUCE
   63: q        BINPUT     3
   65: K        BININT1    1
   67: J        BININT     -1
   72: K        BININT1    255
   74: J        BININT     -255
   79: J        BININT     -256
   84: M        BININT2    65535
   87: J        BININT     -65535
   92: J        BININT     -65536
   97: J        BININT     2147483647
  102: J        BININT     -2147483647
  107: J        BININT     -2147483648
  112: (        MARK
  113: X            BINUNICODE 'abc'
  121: q            BINPUT     4
  123: h            BINGET     4
  125: c            GLOBAL     'copy_reg _reconstructor'
  150: q            BINPUT     5
  152: (            MARK
  153: c                GLOBAL     '__main__ C'
  165: q                BINPUT     6
  167: c                GLOBAL     '__builtin__ object'
  187: q                BINPUT     7
  189: N                NONE
  190: t                TUPLE      (MARK at 152)
  191: q            BINPUT     8
  193: R            REDUCE
  194: q            BINPUT     9
  196: }            EMPTY_DICT
  197: q            BINPUT     10
  199: (            MARK
  200: X                BINUNICODE 'foo'
  208: q                BINPUT     11
  210: K                BININT1    1
  212: X                BINUNICODE 'bar'
  220: q                BINPUT     12
  222: K                BININT1    2
  224: u                SETITEMS   (MARK at 199)
  225: b            BUILD
  226: h            BINGET     9
  228: t            TUPLE      (MARK at 112)
  229: q        BINPUT     13
  231: h        BINGET     13
  233: K        BININT1    5
  235: e        APPENDS    (MARK at 3)
  236: .    STOP
highest protocol among opcodes = 1
"""

DATA2 = (
    b'\x80\x02]q\x00(K\x00K\x01G@\x00\x00\x00\x00\x00\x00\x00c'
    b'__builtin__\ncomplex\n'
    b'q\x01G@\x08\x00\x00\x00\x00\x00\x00G\x00\x00\x00\x00\x00\x00\x00\x00'
    b'\x86q\x02Rq\x03K\x01J\xff\xff\xff\xffK\xffJ\x01\xff\xff\xff'
    b'J\x00\xff\xff\xffM\xff\xffJ\x01\x00\xff\xffJ\x00\x00\xff\xffJ\xff'
    b'\xff\xff\x7fJ\x01\x00\x00\x80J\x00\x00\x00\x80(X\x03\x00\x00\x00a'
    b'bcq\x04h\x04c__main__\nC\nq\x05'
    b')\x81q\x06}q\x07(X\x03\x00\x00\x00fooq\x08K\x01'
    b'X\x03\x00\x00\x00barq\tK\x02ubh\x06tq\nh'
    b'\nK\x05e.'
)

# Disassembly of DATA2
DATA2_DIS = """\
    0: \x80 PROTO      2
    2: ]    EMPTY_LIST
    3: q    BINPUT     0
    5: (    MARK
    6: K        BININT1    0
    8: K        BININT1    1
   10: G        BINFLOAT   2.0
   19: c        GLOBAL     '__builtin__ complex'
   40: q        BINPUT     1
   42: G        BINFLOAT   3.0
   51: G        BINFLOAT   0.0
   60: \x86     TUPLE2
   61: q        BINPUT     2
   63: R        REDUCE
   64: q        BINPUT     3
   66: K        BININT1    1
   68: J        BININT     -1
   73: K        BININT1    255
   75: J        BININT     -255
   80: J        BININT     -256
   85: M        BININT2    65535
   88: J        BININT     -65535
   93: J        BININT     -65536
   98: J        BININT     2147483647
  103: J        BININT     -2147483647
  108: J        BININT     -2147483648
  113: (        MARK
  114: X            BINUNICODE 'abc'
  122: q            BINPUT     4
  124: h            BINGET     4
  126: c            GLOBAL     '__main__ C'
  138: q            BINPUT     5
  140: )            EMPTY_TUPLE
  141: \x81         NEWOBJ
  142: q            BINPUT     6
  144: }            EMPTY_DICT
  145: q            BINPUT     7
  147: (            MARK
  148: X                BINUNICODE 'foo'
  156: q                BINPUT     8
  158: K                BININT1    1
  160: X                BINUNICODE 'bar'
  168: q                BINPUT     9
  170: K                BININT1    2
  172: u                SETITEMS   (MARK at 147)
  173: b            BUILD
  174: h            BINGET     6
  176: t            TUPLE      (MARK at 113)
  177: q        BINPUT     10
  179: h        BINGET     10
  181: K        BININT1    5
  183: e        APPENDS    (MARK at 5)
  184: .    STOP
highest protocol among opcodes = 2
"""

DATA3 = (
    b'\x80\x03]q\x00(K\x00K\x01G@\x00\x00\x00\x00\x00\x00\x00c'
    b'builtins\ncomplex\nq\x01G'
    b'@\x08\x00\x00\x00\x00\x00\x00G\x00\x00\x00\x00\x00\x00\x00\x00\x86q\x02'
    b'Rq\x03K\x01J\xff\xff\xff\xffK\xffJ\x01\xff\xff\xffJ\x00\xff'
    b'\xff\xffM\xff\xffJ\x01\x00\xff\xffJ\x00\x00\xff\xffJ\xff\xff\xff\x7f'
    b'J\x01\x00\x00\x80J\x00\x00\x00\x80(X\x03\x00\x00\x00abcq'
    b'\x04h\x04c__main__\nC\nq\x05)\x81q'
    b'\x06}q\x07(X\x03\x00\x00\x00barq\x08K\x02X\x03\x00'
    b'\x00\x00fooq\tK\x01ubh\x06tq\nh\nK\x05'
    b'e.'
)

# Disassembly of DATA3
DATA3_DIS = """\
    0: \x80 PROTO      3
    2: ]    EMPTY_LIST
    3: q    BINPUT     0
    5: (    MARK
    6: K        BININT1    0
    8: K        BININT1    1
   10: G        BINFLOAT   2.0
   19: c        GLOBAL     'builtins complex'
   37: q        BINPUT     1
   39: G        BINFLOAT   3.0
   48: G        BINFLOAT   0.0
   57: \x86     TUPLE2
   58: q        BINPUT     2
   60: R        REDUCE
   61: q        BINPUT     3
   63: K        BININT1    1
   65: J        BININT     -1
   70: K        BININT1    255
   72: J        BININT     -255
   77: J        BININT     -256
   82: M        BININT2    65535
   85: J        BININT     -65535
   90: J        BININT     -65536
   95: J        BININT     2147483647
  100: J        BININT     -2147483647
  105: J        BININT     -2147483648
  110: (        MARK
  111: X            BINUNICODE 'abc'
  119: q            BINPUT     4
  121: h            BINGET     4
  123: c            GLOBAL     '__main__ C'
  135: q            BINPUT     5
  137: )            EMPTY_TUPLE
  138: \x81         NEWOBJ
  139: q            BINPUT     6
  141: }            EMPTY_DICT
  142: q            BINPUT     7
  144: (            MARK
  145: X                BINUNICODE 'bar'
  153: q                BINPUT     8
  155: K                BININT1    2
  157: X                BINUNICODE 'foo'
  165: q                BINPUT     9
  167: K                BININT1    1
  169: u                SETITEMS   (MARK at 144)
  170: b            BUILD
  171: h            BINGET     6
  173: t            TUPLE      (MARK at 110)
  174: q        BINPUT     10
  176: h        BINGET     10
  178: K        BININT1    5
  180: e        APPENDS    (MARK at 5)
  181: .    STOP
highest protocol among opcodes = 2
"""

DATA4 = (
    b'\x80\x04\x95\xa8\x00\x00\x00\x00\x00\x00\x00]\x94(K\x00K\x01G@'
    b'\x00\x00\x00\x00\x00\x00\x00\x8c\x08builtins\x94\x8c\x07'
    b'complex\x94\x93\x94G@\x08\x00\x00\x00\x00\x00\x00G'
    b'\x00\x00\x00\x00\x00\x00\x00\x00\x86\x94R\x94K\x01J\xff\xff\xff\xffK'
    b'\xffJ\x01\xff\xff\xffJ\x00\xff\xff\xffM\xff\xffJ\x01\x00\xff\xffJ'
    b'\x00\x00\xff\xffJ\xff\xff\xff\x7fJ\x01\x00\x00\x80J\x00\x00\x00\x80('
    b'\x8c\x03abc\x94h\x06\x8c\x08__main__\x94\x8c'
    b'\x01C\x94\x93\x94)\x81\x94}\x94(\x8c\x03bar\x94K\x02\x8c'
    b'\x03foo\x94K\x01ubh\nt\x94h\x0eK\x05e.'
)

# Disassembly of DATA4
DATA4_DIS = """\
    0: \x80 PROTO      4
    2: \x95 FRAME      168
   11: ]    EMPTY_LIST
   12: \x94 MEMOIZE
   13: (    MARK
   14: K        BININT1    0
   16: K        BININT1    1
   18: G        BINFLOAT   2.0
   27: \x8c     SHORT_BINUNICODE 'builtins'
   37: \x94     MEMOIZE
   38: \x8c     SHORT_BINUNICODE 'complex'
   47: \x94     MEMOIZE
   48: \x93     STACK_GLOBAL
   49: \x94     MEMOIZE
   50: G        BINFLOAT   3.0
   59: G        BINFLOAT   0.0
   68: \x86     TUPLE2
   69: \x94     MEMOIZE
   70: R        REDUCE
   71: \x94     MEMOIZE
   72: K        BININT1    1
   74: J        BININT     -1
   79: K        BININT1    255
   81: J        BININT     -255
   86: J        BININT     -256
   91: M        BININT2    65535
   94: J        BININT     -65535
   99: J        BININT     -65536
  104: J        BININT     2147483647
  109: J        BININT     -2147483647
  114: J        BININT     -2147483648
  119: (        MARK
  120: \x8c         SHORT_BINUNICODE 'abc'
  125: \x94         MEMOIZE
  126: h            BINGET     6
  128: \x8c         SHORT_BINUNICODE '__main__'
  138: \x94         MEMOIZE
  139: \x8c         SHORT_BINUNICODE 'C'
  142: \x94         MEMOIZE
  143: \x93         STACK_GLOBAL
  144: \x94         MEMOIZE
  145: )            EMPTY_TUPLE
  146: \x81         NEWOBJ
  147: \x94         MEMOIZE
  148: }            EMPTY_DICT
  149: \x94         MEMOIZE
  150: (            MARK
  151: \x8c             SHORT_BINUNICODE 'bar'
  156: \x94             MEMOIZE
  157: K                BININT1    2
  159: \x8c             SHORT_BINUNICODE 'foo'
  164: \x94             MEMOIZE
  165: K                BININT1    1
  167: u                SETITEMS   (MARK at 150)
  168: b            BUILD
  169: h            BINGET     10
  171: t            TUPLE      (MARK at 119)
  172: \x94     MEMOIZE
  173: h        BINGET     14
  175: K        BININT1    5
  177: e        APPENDS    (MARK at 13)
  178: .    STOP
highest protocol among opcodes = 4
"""

# set([1,2]) pickled from 2.x with protocol 2
DATA_SET = b'\x80\x02c__builtin__\nset\nq\x00]q\x01(K\x01K\x02e\x85q\x02Rq\x03.'

# xrange(5) pickled from 2.x with protocol 2
DATA_XRANGE = b'\x80\x02c__builtin__\nxrange\nq\x00K\x00K\x05K\x01\x87q\x01Rq\x02.'

# a SimpleCookie() object pickled from 2.x with protocol 2
DATA_COOKIE = (b'\x80\x02cCookie\nSimpleCookie\nq\x00)\x81q\x01U\x03key'
               b'q\x02cCookie\nMorsel\nq\x03)\x81q\x04(U\x07commentq\x05U'
               b'\x00q\x06U\x06domainq\x07h\x06U\x06secureq\x08h\x06U\x07'
               b'expiresq\th\x06U\x07max-ageq\nh\x06U\x07versionq\x0bh\x06U'
               b'\x04pathq\x0ch\x06U\x08httponlyq\rh\x06u}q\x0e(U\x0b'
               b'coded_valueq\x0fU\x05valueq\x10h\x10h\x10h\x02h\x02ubs}q\x11b.')

# set([3]) pickled from 2.x with protocol 2
DATA_SET2 = b'\x80\x02c__builtin__\nset\nq\x00]q\x01K\x03a\x85q\x02Rq\x03.'

python2_exceptions_without_args = (
    ArithmeticError,
    AssertionError,
    AttributeError,
    BaseException,
    BufferError,
    BytesWarning,
    DeprecationWarning,
    EOFError,
    EnvironmentError,
    Exception,
    FloatingPointError,
    FutureWarning,
    GeneratorExit,
    IOError,
    ImportError,
    ImportWarning,
    IndentationError,
    IndexError,
    KeyError,
    KeyboardInterrupt,
    LookupError,
    MemoryError,
    NameError,
    NotImplementedError,
    OSError,
    OverflowError,
    PendingDeprecationWarning,
    ReferenceError,
    RuntimeError,
    RuntimeWarning,
    # StandardError is gone in Python 3, we map it to Exception
    StopIteration,
    SyntaxError,
    SyntaxWarning,
    SystemError,
    SystemExit,
    TabError,
    TypeError,
    UnboundLocalError,
    UnicodeError,
    UnicodeWarning,
    UserWarning,
    ValueError,
    Warning,
    ZeroDivisionError,
)

exception_pickle = b'\x80\x02cexceptions\n?\nq\x00)Rq\x01.'

# UnicodeEncodeError object pickled from 2.x with protocol 2
DATA_UEERR = (b'\x80\x02cexceptions\nUnicodeEncodeError\n'
              b'q\x00(U\x05asciiq\x01X\x03\x00\x00\x00fooq\x02K\x00K\x01'
              b'U\x03badq\x03tq\x04Rq\x05.')


def create_data():
    c = C()
    c.foo = 1
    c.bar = 2
    x = [0, 1, 2.0, 3.0+0j]
    # Append some integer test cases at cPickle.c's internal size
    # cutoffs.
    uint1max = 0xff
    uint2max = 0xffff
    int4max = 0x7fffffff
    x.extend([1, -1,
              uint1max, -uint1max, -uint1max-1,
              uint2max, -uint2max, -uint2max-1,
               int4max,  -int4max,  -int4max-1])
    y = ('abc', 'abc', c, c)
    x.append(y)
    x.append(y)
    x.append(5)
    return x


class AbstractUnpickleTests(unittest.TestCase):
    # Subclass must define self.loads.

    _testdata = create_data()

    def assert_is_copy(self, obj, objcopy, msg=None):
        """Utility method to verify if two objects are copies of each others.
        """
        if msg is None:
            msg = "{!r} is not a copy of {!r}".format(obj, objcopy)
        self.assertEqual(obj, objcopy, msg=msg)
        self.assertIs(type(obj), type(objcopy), msg=msg)
        if hasattr(obj, '__dict__'):
            self.assertDictEqual(obj.__dict__, objcopy.__dict__, msg=msg)
            self.assertIsNot(obj.__dict__, objcopy.__dict__, msg=msg)
        if hasattr(obj, '__slots__'):
            self.assertListEqual(obj.__slots__, objcopy.__slots__, msg=msg)
            for slot in obj.__slots__:
                self.assertEqual(
                    hasattr(obj, slot), hasattr(objcopy, slot), msg=msg)
                self.assertEqual(getattr(obj, slot, None),
                                 getattr(objcopy, slot, None), msg=msg)

    def check_unpickling_error(self, errors, data):
        with self.subTest(data=data), \
             self.assertRaises(errors):
            try:
                self.loads(data)
            except BaseException as exc:
                if support.verbose > 1:
                    print('%-32r - %s: %s' %
                          (data, exc.__class__.__name__, exc))
                raise

    def test_load_from_data0(self):
        self.assert_is_copy(self._testdata, self.loads(DATA0))

    def test_load_from_data1(self):
        self.assert_is_copy(self._testdata, self.loads(DATA1))

    def test_load_from_data2(self):
        self.assert_is_copy(self._testdata, self.loads(DATA2))

    def test_load_from_data3(self):
        self.assert_is_copy(self._testdata, self.loads(DATA3))

    def test_load_from_data4(self):
        self.assert_is_copy(self._testdata, self.loads(DATA4))

    def test_load_classic_instance(self):
        # See issue5180.  Test loading 2.x pickles that
        # contain an instance of old style class.
        for X, args in [(C, ()), (D, ('x',)), (E, ())]:
            xname = X.__name__.encode('ascii')
            # Protocol 0 (text mode pickle):
            """
             0: (    MARK
             1: i        INST       '__main__ X' (MARK at 0)
            13: p    PUT        0
            16: (    MARK
            17: d        DICT       (MARK at 16)
            18: p    PUT        1
            21: b    BUILD
            22: .    STOP
            """
            pickle0 = (b"(i__main__\n"
                       b"X\n"
                       b"p0\n"
                       b"(dp1\nb.").replace(b'X', xname)
            self.assert_is_copy(X(*args), self.loads(pickle0))

            # Protocol 1 (binary mode pickle)
            """
             0: (    MARK
             1: c        GLOBAL     '__main__ X'
            13: q        BINPUT     0
            15: o        OBJ        (MARK at 0)
            16: q    BINPUT     1
            18: }    EMPTY_DICT
            19: q    BINPUT     2
            21: b    BUILD
            22: .    STOP
            """
            pickle1 = (b'(c__main__\n'
                       b'X\n'
                       b'q\x00oq\x01}q\x02b.').replace(b'X', xname)
            self.assert_is_copy(X(*args), self.loads(pickle1))

            # Protocol 2 (pickle2 = b'\x80\x02' + pickle1)
            """
             0: \x80 PROTO      2
             2: (    MARK
             3: c        GLOBAL     '__main__ X'
            15: q        BINPUT     0
            17: o        OBJ        (MARK at 2)
            18: q    BINPUT     1
            20: }    EMPTY_DICT
            21: q    BINPUT     2
            23: b    BUILD
            24: .    STOP
            """
            pickle2 = (b'\x80\x02(c__main__\n'
                       b'X\n'
                       b'q\x00oq\x01}q\x02b.').replace(b'X', xname)
            self.assert_is_copy(X(*args), self.loads(pickle2))

    def test_maxint64(self):
        maxint64 = (1 << 63) - 1
        data = b'I' + str(maxint64).encode("ascii") + b'\n.'
        got = self.loads(data)
        self.assert_is_copy(maxint64, got)

        # Try too with a bogus literal.
        data = b'I' + str(maxint64).encode("ascii") + b'JUNK\n.'
        self.check_unpickling_error(ValueError, data)

    def test_unpickle_from_2x(self):
        # Unpickle non-trivial data from Python 2.x.
        loaded = self.loads(DATA_SET)
        self.assertEqual(loaded, set([1, 2]))
        loaded = self.loads(DATA_XRANGE)
        self.assertEqual(type(loaded), type(range(0)))
        self.assertEqual(list(loaded), list(range(5)))
        loaded = self.loads(DATA_COOKIE)
        self.assertEqual(type(loaded), SimpleCookie)
        self.assertEqual(list(loaded.keys()), ["key"])
        self.assertEqual(loaded["key"].value, "value")

        # Exception objects without arguments pickled from 2.x with protocol 2
        for exc in python2_exceptions_without_args:
            data = exception_pickle.replace(b'?', exc.__name__.encode("ascii"))
            loaded = self.loads(data)
            self.assertIs(type(loaded), exc)

        # StandardError is mapped to Exception, test that separately
        loaded = self.loads(exception_pickle.replace(b'?', b'StandardError'))
        self.assertIs(type(loaded), Exception)

        loaded = self.loads(DATA_UEERR)
        self.assertIs(type(loaded), UnicodeEncodeError)
        self.assertEqual(loaded.object, "foo")
        self.assertEqual(loaded.encoding, "ascii")
        self.assertEqual(loaded.start, 0)
        self.assertEqual(loaded.end, 1)
        self.assertEqual(loaded.reason, "bad")

    def test_load_python2_str_as_bytes(self):
        # From Python 2: pickle.dumps('a\x00\xa0', protocol=0)
        self.assertEqual(self.loads(b"S'a\\x00\\xa0'\n.",
                                    encoding="bytes"), b'a\x00\xa0')
        # From Python 2: pickle.dumps('a\x00\xa0', protocol=1)
        self.assertEqual(self.loads(b'U\x03a\x00\xa0.',
                                    encoding="bytes"), b'a\x00\xa0')
        # From Python 2: pickle.dumps('a\x00\xa0', protocol=2)
        self.assertEqual(self.loads(b'\x80\x02U\x03a\x00\xa0.',
                                    encoding="bytes"), b'a\x00\xa0')

    def test_load_python2_unicode_as_str(self):
        # From Python 2: pickle.dumps(u'π', protocol=0)
        self.assertEqual(self.loads(b'V\\u03c0\n.',
                                    encoding='bytes'), 'π')
        # From Python 2: pickle.dumps(u'π', protocol=1)
        self.assertEqual(self.loads(b'X\x02\x00\x00\x00\xcf\x80.',
                                    encoding="bytes"), 'π')
        # From Python 2: pickle.dumps(u'π', protocol=2)
        self.assertEqual(self.loads(b'\x80\x02X\x02\x00\x00\x00\xcf\x80.',
                                    encoding="bytes"), 'π')

    def test_load_long_python2_str_as_bytes(self):
        # From Python 2: pickle.dumps('x' * 300, protocol=1)
        self.assertEqual(self.loads(pickle.BINSTRING +
                                    struct.pack("<I", 300) +
                                    b'x' * 300 + pickle.STOP,
                                    encoding='bytes'), b'x' * 300)

    def test_constants(self):
        self.assertIsNone(self.loads(b'N.'))
        self.assertIs(self.loads(b'\x88.'), True)
        self.assertIs(self.loads(b'\x89.'), False)
        self.assertIs(self.loads(b'I01\n.'), True)
        self.assertIs(self.loads(b'I00\n.'), False)

    def test_empty_bytestring(self):
        # issue 11286
        empty = self.loads(b'\x80\x03U\x00q\x00.', encoding='koi8-r')
        self.assertEqual(empty, '')

    def test_short_binbytes(self):
        dumped = b'\x80\x03C\x04\xe2\x82\xac\x00.'
        self.assertEqual(self.loads(dumped), b'\xe2\x82\xac\x00')

    def test_binbytes(self):
        dumped = b'\x80\x03B\x04\x00\x00\x00\xe2\x82\xac\x00.'
        self.assertEqual(self.loads(dumped), b'\xe2\x82\xac\x00')

    @requires_32b
    def test_negative_32b_binbytes(self):
        # On 32-bit builds, a BINBYTES of 2**31 or more is refused
        dumped = b'\x80\x03B\xff\xff\xff\xffxyzq\x00.'
        self.check_unpickling_error((pickle.UnpicklingError, OverflowError),
                                    dumped)

    @requires_32b
    def test_negative_32b_binunicode(self):
        # On 32-bit builds, a BINUNICODE of 2**31 or more is refused
        dumped = b'\x80\x03X\xff\xff\xff\xffxyzq\x00.'
        self.check_unpickling_error((pickle.UnpicklingError, OverflowError),
                                    dumped)

    def test_short_binunicode(self):
        dumped = b'\x80\x04\x8c\x04\xe2\x82\xac\x00.'
        self.assertEqual(self.loads(dumped), '\u20ac\x00')

    def test_misc_get(self):
        self.check_unpickling_error(KeyError, b'g0\np0')
        self.assert_is_copy([(100,), (100,)],
                            self.loads(b'((Kdtp0\nh\x00l.))'))

    def test_binbytes8(self):
        dumped = b'\x80\x04\x8e\4\0\0\0\0\0\0\0\xe2\x82\xac\x00.'
        self.assertEqual(self.loads(dumped), b'\xe2\x82\xac\x00')

    def test_binunicode8(self):
        dumped = b'\x80\x04\x8d\4\0\0\0\0\0\0\0\xe2\x82\xac\x00.'
        self.assertEqual(self.loads(dumped), '\u20ac\x00')

    def test_bytearray8(self):
        dumped = b'\x80\x05\x96\x03\x00\x00\x00\x00\x00\x00\x00xxx.'
        self.assertEqual(self.loads(dumped), bytearray(b'xxx'))

    @requires_32b
    def test_large_32b_binbytes8(self):
        dumped = b'\x80\x04\x8e\4\0\0\0\1\0\0\0\xe2\x82\xac\x00.'
        self.check_unpickling_error((pickle.UnpicklingError, OverflowError),
                                    dumped)

    @requires_32b
    def test_large_32b_bytearray8(self):
        dumped = b'\x80\x05\x96\4\0\0\0\1\0\0\0\xe2\x82\xac\x00.'
        self.check_unpickling_error((pickle.UnpicklingError, OverflowError),
                                    dumped)

    @requires_32b
    def test_large_32b_binunicode8(self):
        dumped = b'\x80\x04\x8d\4\0\0\0\1\0\0\0\xe2\x82\xac\x00.'
        self.check_unpickling_error((pickle.UnpicklingError, OverflowError),
                                    dumped)

    def test_get(self):
        pickled = b'((lp100000\ng100000\nt.'
        unpickled = self.loads(pickled)
        self.assertEqual(unpickled, ([],)*2)
        self.assertIs(unpickled[0], unpickled[1])

    def test_binget(self):
        pickled = b'(]q\xffh\xfft.'
        unpickled = self.loads(pickled)
        self.assertEqual(unpickled, ([],)*2)
        self.assertIs(unpickled[0], unpickled[1])

    def test_long_binget(self):
        pickled = b'(]r\x00\x00\x01\x00j\x00\x00\x01\x00t.'
        unpickled = self.loads(pickled)
        self.assertEqual(unpickled, ([],)*2)
        self.assertIs(unpickled[0], unpickled[1])

    def test_dup(self):
        pickled = b'((l2t.'
        unpickled = self.loads(pickled)
        self.assertEqual(unpickled, ([],)*2)
        self.assertIs(unpickled[0], unpickled[1])

    def test_negative_put(self):
        # Issue #12847
        dumped = b'Va\np-1\n.'
        self.check_unpickling_error(ValueError, dumped)

    @requires_32b
    def test_negative_32b_binput(self):
        # Issue #12847
        dumped = b'\x80\x03X\x01\x00\x00\x00ar\xff\xff\xff\xff.'
        self.check_unpickling_error(ValueError, dumped)

    def test_badly_escaped_string(self):
        self.check_unpickling_error(ValueError, b"S'\\'\n.")

    def test_badly_quoted_string(self):
        # Issue #17710
        badpickles = [b"S'\n.",
                      b'S"\n.',
                      b'S\' \n.',
                      b'S" \n.',
                      b'S\'"\n.',
                      b'S"\'\n.',
                      b"S' ' \n.",
                      b'S" " \n.',
                      b"S ''\n.",
                      b'S ""\n.',
                      b'S \n.',
                      b'S\n.',
                      b'S.']
        for p in badpickles:
            self.check_unpickling_error(pickle.UnpicklingError, p)

    def test_correctly_quoted_string(self):
        goodpickles = [(b"S''\n.", ''),
                       (b'S""\n.', ''),
                       (b'S"\\n"\n.', '\n'),
                       (b"S'\\n'\n.", '\n')]
        for p, expected in goodpickles:
            self.assertEqual(self.loads(p), expected)

    def test_frame_readline(self):
        pickled = b'\x80\x04\x95\x05\x00\x00\x00\x00\x00\x00\x00I42\n.'
        #    0: \x80 PROTO      4
        #    2: \x95 FRAME      5
        #   11: I    INT        42
        #   15: .    STOP
        self.assertEqual(self.loads(pickled), 42)

    def test_compat_unpickle(self):
        # xrange(1, 7)
        pickled = b'\x80\x02c__builtin__\nxrange\nK\x01K\x07K\x01\x87R.'
        unpickled = self.loads(pickled)
        self.assertIs(type(unpickled), range)
        self.assertEqual(unpickled, range(1, 7))
        self.assertEqual(list(unpickled), [1, 2, 3, 4, 5, 6])
        # reduce
        pickled = b'\x80\x02c__builtin__\nreduce\n.'
        self.assertIs(self.loads(pickled), functools.reduce)
        # whichdb.whichdb
        pickled = b'\x80\x02cwhichdb\nwhichdb\n.'
        self.assertIs(self.loads(pickled), dbm.whichdb)
        # Exception(), StandardError()
        for name in (b'Exception', b'StandardError'):
            pickled = (b'\x80\x02cexceptions\n' + name + b'\nU\x03ugh\x85R.')
            unpickled = self.loads(pickled)
            self.assertIs(type(unpickled), Exception)
            self.assertEqual(str(unpickled), 'ugh')
        # UserDict.UserDict({1: 2}), UserDict.IterableUserDict({1: 2})
        for name in (b'UserDict', b'IterableUserDict'):
            pickled = (b'\x80\x02(cUserDict\n' + name +
                       b'\no}U\x04data}K\x01K\x02ssb.')
            unpickled = self.loads(pickled)
            self.assertIs(type(unpickled), collections.UserDict)
            self.assertEqual(unpickled, collections.UserDict({1: 2}))

    def test_bad_stack(self):
        badpickles = [
            b'.',                       # STOP
            b'0',                       # POP
            b'1',                       # POP_MARK
            b'2',                       # DUP
            b'(2',
            b'R',                       # REDUCE
            b')R',
            b'a',                       # APPEND
            b'Na',
            b'b',                       # BUILD
            b'Nb',
            b'd',                       # DICT
            b'e',                       # APPENDS
            b'(e',
            b'ibuiltins\nlist\n',       # INST
            b'l',                       # LIST
            b'o',                       # OBJ
            b'(o',
            b'p1\n',                    # PUT
            b'q\x00',                   # BINPUT
            b'r\x00\x00\x00\x00',       # LONG_BINPUT
            b's',                       # SETITEM
            b'Ns',
            b'NNs',
            b't',                       # TUPLE
            b'u',                       # SETITEMS
            b'(u',
            b'}(Nu',
            b'\x81',                    # NEWOBJ
            b')\x81',
            b'\x85',                    # TUPLE1
            b'\x86',                    # TUPLE2
            b'N\x86',
            b'\x87',                    # TUPLE3
            b'N\x87',
            b'NN\x87',
            b'\x90',                    # ADDITEMS
            b'(\x90',
            b'\x91',                    # FROZENSET
            b'\x92',                    # NEWOBJ_EX
            b')}\x92',
            b'\x93',                    # STACK_GLOBAL
            b'Vlist\n\x93',
            b'\x94',                    # MEMOIZE
        ]
        for p in badpickles:
            self.check_unpickling_error(self.bad_stack_errors, p)

    def test_bad_mark(self):
        badpickles = [
            b'N(.',                     # STOP
            b'N(2',                     # DUP
            b'cbuiltins\nlist\n)(R',    # REDUCE
            b'cbuiltins\nlist\n()R',
            b']N(a',                    # APPEND
                                        # BUILD
            b'cbuiltins\nValueError\n)R}(b',
            b'cbuiltins\nValueError\n)R(}b',
            b'(Nd',                     # DICT
            b'N(p1\n',                  # PUT
            b'N(q\x00',                 # BINPUT
            b'N(r\x00\x00\x00\x00',     # LONG_BINPUT
            b'}NN(s',                   # SETITEM
            b'}N(Ns',
            b'}(NNs',
            b'}((u',                    # SETITEMS
            b'cbuiltins\nlist\n)(\x81', # NEWOBJ
            b'cbuiltins\nlist\n()\x81',
            b'N(\x85',                  # TUPLE1
            b'NN(\x86',                 # TUPLE2
            b'N(N\x86',
            b'NNN(\x87',                # TUPLE3
            b'NN(N\x87',
            b'N(NN\x87',
            b']((\x90',                 # ADDITEMS
                                        # NEWOBJ_EX
            b'cbuiltins\nlist\n)}(\x92',
            b'cbuiltins\nlist\n)(}\x92',
            b'cbuiltins\nlist\n()}\x92',
                                        # STACK_GLOBAL
            b'Vbuiltins\n(Vlist\n\x93',
            b'Vbuiltins\nVlist\n(\x93',
            b'N(\x94',                  # MEMOIZE
        ]
        for p in badpickles:
            self.check_unpickling_error(self.bad_stack_errors, p)

    def test_truncated_data(self):
        self.check_unpickling_error(EOFError, b'')
        self.check_unpickling_error(EOFError, b'N')
        badpickles = [
            b'B',                       # BINBYTES
            b'B\x03\x00\x00',
            b'B\x03\x00\x00\x00',
            b'B\x03\x00\x00\x00ab',
            b'C',                       # SHORT_BINBYTES
            b'C\x03',
            b'C\x03ab',
            b'F',                       # FLOAT
            b'F0.0',
            b'F0.00',
            b'G',                       # BINFLOAT
            b'G\x00\x00\x00\x00\x00\x00\x00',
            b'I',                       # INT
            b'I0',
            b'J',                       # BININT
            b'J\x00\x00\x00',
            b'K',                       # BININT1
            b'L',                       # LONG
            b'L0',
            b'L10',
            b'L0L',
            b'L10L',
            b'M',                       # BININT2
            b'M\x00',
            # b'P',                       # PERSID
            # b'Pabc',
            b'S',                       # STRING
            b"S'abc'",
            b'T',                       # BINSTRING
            b'T\x03\x00\x00',
            b'T\x03\x00\x00\x00',
            b'T\x03\x00\x00\x00ab',
            b'U',                       # SHORT_BINSTRING
            b'U\x03',
            b'U\x03ab',
            b'V',                       # UNICODE
            b'Vabc',
            b'X',                       # BINUNICODE
            b'X\x03\x00\x00',
            b'X\x03\x00\x00\x00',
            b'X\x03\x00\x00\x00ab',
            b'(c',                      # GLOBAL
            b'(cbuiltins',
            b'(cbuiltins\n',
            b'(cbuiltins\nlist',
            b'Ng',                      # GET
            b'Ng0',
            b'(i',                      # INST
            b'(ibuiltins',
            b'(ibuiltins\n',
            b'(ibuiltins\nlist',
            b'Nh',                      # BINGET
            b'Nj',                      # LONG_BINGET
            b'Nj\x00\x00\x00',
            b'Np',                      # PUT
            b'Np0',
            b'Nq',                      # BINPUT
            b'Nr',                      # LONG_BINPUT
            b'Nr\x00\x00\x00',
            b'\x80',                    # PROTO
            b'\x82',                    # EXT1
            b'\x83',                    # EXT2
            b'\x84\x01',
            b'\x84',                    # EXT4
            b'\x84\x01\x00\x00',
            b'\x8a',                    # LONG1
            b'\x8b',                    # LONG4
            b'\x8b\x00\x00\x00',
            b'\x8c',                    # SHORT_BINUNICODE
            b'\x8c\x03',
            b'\x8c\x03ab',
            b'\x8d',                    # BINUNICODE8
            b'\x8d\x03\x00\x00\x00\x00\x00\x00',
            b'\x8d\x03\x00\x00\x00\x00\x00\x00\x00',
            b'\x8d\x03\x00\x00\x00\x00\x00\x00\x00ab',
            b'\x8e',                    # BINBYTES8
            b'\x8e\x03\x00\x00\x00\x00\x00\x00',
            b'\x8e\x03\x00\x00\x00\x00\x00\x00\x00',
            b'\x8e\x03\x00\x00\x00\x00\x00\x00\x00ab',
            b'\x96',                    # BYTEARRAY8
            b'\x96\x03\x00\x00\x00\x00\x00\x00',
            b'\x96\x03\x00\x00\x00\x00\x00\x00\x00',
            b'\x96\x03\x00\x00\x00\x00\x00\x00\x00ab',
            b'\x95',                    # FRAME
            b'\x95\x02\x00\x00\x00\x00\x00\x00',
            b'\x95\x02\x00\x00\x00\x00\x00\x00\x00',
            b'\x95\x02\x00\x00\x00\x00\x00\x00\x00N',
        ]
        for p in badpickles:
            self.check_unpickling_error(self.truncated_errors, p)


class AbstractPickleTests(unittest.TestCase):
    # Subclass must define self.dumps, self.loads.

    optimized = False

    _testdata = AbstractUnpickleTests._testdata

    def setUp(self):
        pass

    assert_is_copy = AbstractUnpickleTests.assert_is_copy

    def test_misc(self):
        # test various datatypes not tested by testdata
        for proto in protocols:
            x = myint(4)
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)

            x = (1, ())
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)

            x = initarg(1, x)
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)

        # XXX test __reduce__ protocol?

    def test_roundtrip_equality(self):
        expected = self._testdata
        for proto in protocols:
            s = self.dumps(expected, proto)
            got = self.loads(s)
            self.assert_is_copy(expected, got)

    # There are gratuitous differences between pickles produced by
    # pickle and cPickle, largely because cPickle starts PUT indices at
    # 1 and pickle starts them at 0.  See XXX comment in cPickle's put2() --
    # there's a comment with an exclamation point there whose meaning
    # is a mystery.  cPickle also suppresses PUT for objects with a refcount
    # of 1.
    def dont_test_disassembly(self):
        from io import StringIO

        for proto, expected in (0, DATA0_DIS), (1, DATA1_DIS):
            s = self.dumps(self._testdata, proto)
            filelike = StringIO()
            pickletools.dis(s, out=filelike)
            got = filelike.getvalue()
            self.assertEqual(expected, got)

    def test_recursive_list(self):
        l = []
        l.append(l)
        for proto in protocols:
            s = self.dumps(l, proto)
            x = self.loads(s)
            self.assertIsInstance(x, list)
            self.assertEqual(len(x), 1)
            self.assertIs(x[0], x)

    def test_recursive_tuple_and_list(self):
        t = ([],)
        t[0].append(t)
        for proto in protocols:
            s = self.dumps(t, proto)
            x = self.loads(s)
            self.assertIsInstance(x, tuple)
            self.assertEqual(len(x), 1)
            self.assertIsInstance(x[0], list)
            self.assertEqual(len(x[0]), 1)
            self.assertIs(x[0][0], x)

    def test_recursive_dict(self):
        d = {}
        d[1] = d
        for proto in protocols:
            s = self.dumps(d, proto)
            x = self.loads(s)
            self.assertIsInstance(x, dict)
            self.assertEqual(list(x.keys()), [1])
            self.assertIs(x[1], x)

    def test_recursive_dict_key(self):
        d = {}
        k = K(d)
        d[k] = 1
        for proto in protocols:
            s = self.dumps(d, proto)
            x = self.loads(s)
            self.assertIsInstance(x, dict)
            self.assertEqual(len(x.keys()), 1)
            self.assertIsInstance(list(x.keys())[0], K)
            self.assertIs(list(x.keys())[0].value, x)

    def test_recursive_set(self):
        y = set()
        k = K(y)
        y.add(k)
        for proto in range(4, pickle.HIGHEST_PROTOCOL + 1):
            s = self.dumps(y, proto)
            x = self.loads(s)
            self.assertIsInstance(x, set)
            self.assertEqual(len(x), 1)
            self.assertIsInstance(list(x)[0], K)
            self.assertIs(list(x)[0].value, x)

    def test_recursive_list_subclass(self):
        y = MyList()
        y.append(y)
        for proto in range(2, pickle.HIGHEST_PROTOCOL + 1):
            s = self.dumps(y, proto)
            x = self.loads(s)
            self.assertIsInstance(x, MyList)
            self.assertEqual(len(x), 1)
            self.assertIs(x[0], x)

    def test_recursive_dict_subclass(self):
        d = MyDict()
        d[1] = d
        for proto in range(2, pickle.HIGHEST_PROTOCOL + 1):
            s = self.dumps(d, proto)
            x = self.loads(s)
            self.assertIsInstance(x, MyDict)
            self.assertEqual(list(x.keys()), [1])
            self.assertIs(x[1], x)

    def test_recursive_dict_subclass_key(self):
        d = MyDict()
        k = K(d)
        d[k] = 1
        for proto in range(2, pickle.HIGHEST_PROTOCOL + 1):
            s = self.dumps(d, proto)
            x = self.loads(s)
            self.assertIsInstance(x, MyDict)
            self.assertEqual(len(list(x.keys())), 1)
            self.assertIsInstance(list(x.keys())[0], K)
            self.assertIs(list(x.keys())[0].value, x)

    def test_recursive_inst(self):
        i = C()
        i.attr = i
        for proto in protocols:
            s = self.dumps(i, proto)
            x = self.loads(s)
            self.assertIsInstance(x, C)
            self.assertEqual(dir(x), dir(i))
            self.assertIs(x.attr, x)

    def test_recursive_multi(self):
        l = []
        d = {1:l}
        i = C()
        i.attr = d
        l.append(i)
        for proto in protocols:
            s = self.dumps(l, proto)
            x = self.loads(s)
            self.assertIsInstance(x, list)
            self.assertEqual(len(x), 1)
            self.assertEqual(dir(x[0]), dir(i))
            self.assertEqual(list(x[0].attr.keys()), [1])
            self.assertTrue(x[0].attr[1] is x)

    def check_recursive_collection_and_inst(self, factory):
        h = H()
        y = factory([h])
        h.attr = y
        for proto in protocols:
            s = self.dumps(y, proto)
            x = self.loads(s)
            self.assertIsInstance(x, type(y))
            self.assertEqual(len(x), 1)
            self.assertIsInstance(list(x)[0], H)
            self.assertIs(list(x)[0].attr, x)

    def test_recursive_list_and_inst(self):
        self.check_recursive_collection_and_inst(list)

    def test_recursive_tuple_and_inst(self):
        self.check_recursive_collection_and_inst(tuple)

    def test_recursive_dict_and_inst(self):
        self.check_recursive_collection_and_inst(dict.fromkeys)

    def test_recursive_set_and_inst(self):
        self.check_recursive_collection_and_inst(set)

    def test_recursive_frozenset_and_inst(self):
        self.check_recursive_collection_and_inst(frozenset)

    def test_recursive_list_subclass_and_inst(self):
        self.check_recursive_collection_and_inst(MyList)

    def test_recursive_tuple_subclass_and_inst(self):
        self.check_recursive_collection_and_inst(MyTuple)

    def test_recursive_dict_subclass_and_inst(self):
        self.check_recursive_collection_and_inst(MyDict.fromkeys)

    def test_recursive_set_subclass_and_inst(self):
        self.check_recursive_collection_and_inst(MySet)

    def test_recursive_frozenset_subclass_and_inst(self):
        self.check_recursive_collection_and_inst(MyFrozenSet)

    def test_unicode(self):
        endcases = ['', '<\\u>', '<\\\u1234>', '<\n>',
                    '<\\>', '<\\\U00012345>',
                    # surrogates
                    '<\udc80>']
        for proto in protocols:
            for u in endcases:
                p = self.dumps(u, proto)
                u2 = self.loads(p)
                self.assert_is_copy(u, u2)

    def test_unicode_high_plane(self):
        t = '\U00012345'
        for proto in protocols:
            p = self.dumps(t, proto)
            t2 = self.loads(p)
            self.assert_is_copy(t, t2)

    def test_bytes(self):
        for proto in protocols:
            for s in b'', b'xyz', b'xyz'*100:
                p = self.dumps(s, proto)
                self.assert_is_copy(s, self.loads(p))
            for s in [bytes([i]) for i in range(256)]:
                p = self.dumps(s, proto)
                self.assert_is_copy(s, self.loads(p))
            for s in [bytes([i, i]) for i in range(256)]:
                p = self.dumps(s, proto)
                self.assert_is_copy(s, self.loads(p))

    def test_bytearray(self):
        for proto in protocols:
            for s in b'', b'xyz', b'xyz'*100:
                b = bytearray(s)
                p = self.dumps(b, proto)
                bb = self.loads(p)
                self.assertIsNot(bb, b)
                self.assert_is_copy(b, bb)
                if proto <= 3:
                    # bytearray is serialized using a global reference
                    self.assertIn(b'bytearray', p)
                    self.assertTrue(opcode_in_pickle(pickle.GLOBAL, p))
                elif proto == 4:
                    self.assertIn(b'bytearray', p)
                    self.assertTrue(opcode_in_pickle(pickle.STACK_GLOBAL, p))
                elif proto == 5:
                    self.assertNotIn(b'bytearray', p)
                    self.assertTrue(opcode_in_pickle(pickle.BYTEARRAY8, p))

    def test_ints(self):
        for proto in protocols:
            n = sys.maxsize
            while n:
                for expected in (-n, n):
                    s = self.dumps(expected, proto)
                    n2 = self.loads(s)
                    self.assert_is_copy(expected, n2)
                n = n >> 1

    def test_long(self):
        for proto in protocols:
            # 256 bytes is where LONG4 begins.
            for nbits in 1, 8, 8*254, 8*255, 8*256, 8*257:
                nbase = 1 << nbits
                for npos in nbase-1, nbase, nbase+1:
                    for n in npos, -npos:
                        pickle = self.dumps(n, proto)
                        got = self.loads(pickle)
                        self.assert_is_copy(n, got)
        # Try a monster.  This is quadratic-time in protos 0 & 1, so don't
        # bother with those.
        nbase = int("deadbeeffeedface", 16)
        nbase += nbase << 1000000
        for n in nbase, -nbase:
            p = self.dumps(n, 2)
            got = self.loads(p)
            # assert_is_copy is very expensive here as it precomputes
            # a failure message by computing the repr() of n and got,
            # we just do the check ourselves.
            self.assertIs(type(got), int)
            self.assertEqual(n, got)

    def test_float(self):
        test_values = [0.0, 4.94e-324, 1e-310, 7e-308, 6.626e-34, 0.1, 0.5,
                       3.14, 263.44582062374053, 6.022e23, 1e30]
        test_values = test_values + [-x for x in test_values]
        for proto in protocols:
            for value in test_values:
                pickle = self.dumps(value, proto)
                got = self.loads(pickle)
                self.assert_is_copy(value, got)

    @run_with_locale('LC_ALL', 'de_DE', 'fr_FR')
    def test_float_format(self):
        # make sure that floats are formatted locale independent with proto 0
        self.assertEqual(self.dumps(1.2, 0)[0:3], b'F1.')

    def test_reduce(self):
        for proto in protocols:
            inst = AAA()
            dumped = self.dumps(inst, proto)
            loaded = self.loads(dumped)
            self.assertEqual(loaded, REDUCE_A)

    def test_getinitargs(self):
        for proto in protocols:
            inst = initarg(1, 2)
            dumped = self.dumps(inst, proto)
            loaded = self.loads(dumped)
            self.assert_is_copy(inst, loaded)

    def test_metaclass(self):
        a = use_metaclass()
        for proto in protocols:
            s = self.dumps(a, proto)
            b = self.loads(s)
            self.assertEqual(a.__class__, b.__class__)

    def test_dynamic_class(self):
        a = create_dynamic_class("my_dynamic_class", (object,))
        copyreg.pickle(pickling_metaclass, pickling_metaclass.__reduce__)
        for proto in protocols:
            s = self.dumps(a, proto)
            b = self.loads(s)
            self.assertEqual(a, b)
            self.assertIs(type(a), type(b))

    def test_structseq(self):
        import time
        import os

        t = time.localtime()
        for proto in protocols:
            s = self.dumps(t, proto)
            u = self.loads(s)
            self.assert_is_copy(t, u)
            if hasattr(os, "stat"):
                t = os.stat(os.curdir)
                s = self.dumps(t, proto)
                u = self.loads(s)
                self.assert_is_copy(t, u)
            if hasattr(os, "statvfs"):
                t = os.statvfs(os.curdir)
                s = self.dumps(t, proto)
                u = self.loads(s)
                self.assert_is_copy(t, u)

    def test_ellipsis(self):
        for proto in protocols:
            s = self.dumps(..., proto)
            u = self.loads(s)
            self.assertIs(..., u)

    def test_notimplemented(self):
        for proto in protocols:
            s = self.dumps(NotImplemented, proto)
            u = self.loads(s)
            self.assertIs(NotImplemented, u)

    def test_singleton_types(self):
        # Issue #6477: Test that types of built-in singletons can be pickled.
        singletons = [None, ..., NotImplemented]
        for singleton in singletons:
            for proto in protocols:
                s = self.dumps(type(singleton), proto)
                u = self.loads(s)
                self.assertIs(type(singleton), u)

    # Tests for protocol 2

    def test_proto(self):
        for proto in protocols:
            pickled = self.dumps(None, proto)
            if proto >= 2:
                proto_header = pickle.PROTO + bytes([proto])
                self.assertTrue(pickled.startswith(proto_header))
            else:
                self.assertEqual(count_opcode(pickle.PROTO, pickled), 0)

        oob = protocols[-1] + 1     # a future protocol
        build_none = pickle.NONE + pickle.STOP
        badpickle = pickle.PROTO + bytes([oob]) + build_none
        try:
            self.loads(badpickle)
        except ValueError as err:
            self.assertIn("unsupported pickle protocol", str(err))
        else:
            self.fail("expected bad protocol number to raise ValueError")

    def test_long1(self):
        x = 12345678910111213141516178920
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            self.assertEqual(opcode_in_pickle(pickle.LONG1, s), proto >= 2)

    def test_long4(self):
        x = 12345678910111213141516178920 << (256*8)
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            self.assertEqual(opcode_in_pickle(pickle.LONG4, s), proto >= 2)

    def test_short_tuples(self):
        # Map (proto, len(tuple)) to expected opcode.
        expected_opcode = {(0, 0): pickle.TUPLE,
                           (0, 1): pickle.TUPLE,
                           (0, 2): pickle.TUPLE,
                           (0, 3): pickle.TUPLE,
                           (0, 4): pickle.TUPLE,

                           (1, 0): pickle.EMPTY_TUPLE,
                           (1, 1): pickle.TUPLE,
                           (1, 2): pickle.TUPLE,
                           (1, 3): pickle.TUPLE,
                           (1, 4): pickle.TUPLE,

                           (2, 0): pickle.EMPTY_TUPLE,
                           (2, 1): pickle.TUPLE1,
                           (2, 2): pickle.TUPLE2,
                           (2, 3): pickle.TUPLE3,
                           (2, 4): pickle.TUPLE,

                           (3, 0): pickle.EMPTY_TUPLE,
                           (3, 1): pickle.TUPLE1,
                           (3, 2): pickle.TUPLE2,
                           (3, 3): pickle.TUPLE3,
                           (3, 4): pickle.TUPLE,
                          }
        a = ()
        b = (1,)
        c = (1, 2)
        d = (1, 2, 3)
        e = (1, 2, 3, 4)
        for proto in protocols:
            for x in a, b, c, d, e:
                s = self.dumps(x, proto)
                y = self.loads(s)
                self.assert_is_copy(x, y)
                expected = expected_opcode[min(proto, 3), len(x)]
                self.assertTrue(opcode_in_pickle(expected, s))

    def test_singletons(self):
        # Map (proto, singleton) to expected opcode.
        expected_opcode = {(0, None): pickle.NONE,
                           (1, None): pickle.NONE,
                           (2, None): pickle.NONE,
                           (3, None): pickle.NONE,

                           (0, True): pickle.INT,
                           (1, True): pickle.INT,
                           (2, True): pickle.NEWTRUE,
                           (3, True): pickle.NEWTRUE,

                           (0, False): pickle.INT,
                           (1, False): pickle.INT,
                           (2, False): pickle.NEWFALSE,
                           (3, False): pickle.NEWFALSE,
                          }
        for proto in protocols:
            for x in None, False, True:
                s = self.dumps(x, proto)
                y = self.loads(s)
                self.assertTrue(x is y, (proto, x, s, y))
                expected = expected_opcode[min(proto, 3), x]
                self.assertTrue(opcode_in_pickle(expected, s))

    def test_newobj_tuple(self):
        x = MyTuple([1, 2, 3])
        x.foo = 42
        x.bar = "hello"
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)

    def test_newobj_list(self):
        x = MyList([1, 2, 3])
        x.foo = 42
        x.bar = "hello"
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)

    def test_newobj_generic(self):
        for proto in protocols:
            for C in myclasses:
                B = C.__base__
                x = C(C.sample)
                x.foo = 42
                s = self.dumps(x, proto)
                y = self.loads(s)
                detail = (proto, C, B, x, y, type(y))
                self.assert_is_copy(x, y) # XXX revisit
                self.assertEqual(B(x), B(y), detail)
                self.assertEqual(x.__dict__, y.__dict__, detail)

    def test_newobj_proxies(self):
        # NEWOBJ should use the __class__ rather than the raw type
        classes = myclasses[:]
        # Cannot create weakproxies to these classes
        for c in (MyInt, MyTuple):
            classes.remove(c)
        for proto in protocols:
            for C in classes:
                B = C.__base__
                x = C(C.sample)
                x.foo = 42
                p = weakref.proxy(x)
                s = self.dumps(p, proto)
                y = self.loads(s)
                self.assertEqual(type(y), type(x))  # rather than type(p)
                detail = (proto, C, B, x, y, type(y))
                self.assertEqual(B(x), B(y), detail)
                self.assertEqual(x.__dict__, y.__dict__, detail)

    def test_newobj_not_class(self):
        # Issue 24552
        global SimpleNewObj
        save = SimpleNewObj
        o = SimpleNewObj.__new__(SimpleNewObj)
        b = self.dumps(o, 4)
        try:
            SimpleNewObj = 42
            self.assertRaises((TypeError, pickle.UnpicklingError), self.loads, b)
        finally:
            SimpleNewObj = save

    # Register a type with copyreg, with extension code extcode.  Pickle
    # an object of that type.  Check that the resulting pickle uses opcode
    # (EXT[124]) under proto 2, and not in proto 1.

    def produce_global_ext(self, extcode, opcode):
        e = ExtensionSaver(extcode)
        try:
            copyreg.add_extension(__name__, "MyList", extcode)
            x = MyList([1, 2, 3])
            x.foo = 42
            x.bar = "hello"

            # Dump using protocol 1 for comparison.
            s1 = self.dumps(x, 1)
            self.assertIn(__name__.encode("utf-8"), s1)
            self.assertIn(b"MyList", s1)
            self.assertFalse(opcode_in_pickle(opcode, s1))

            y = self.loads(s1)
            self.assert_is_copy(x, y)

            # Dump using protocol 2 for test.
            s2 = self.dumps(x, 2)
            self.assertNotIn(__name__.encode("utf-8"), s2)
            self.assertNotIn(b"MyList", s2)
            self.assertEqual(opcode_in_pickle(opcode, s2), True, repr(s2))

            y = self.loads(s2)
            self.assert_is_copy(x, y)
        finally:
            e.restore()

    def test_global_ext1(self):
        self.produce_global_ext(0x00000001, pickle.EXT1)  # smallest EXT1 code
        self.produce_global_ext(0x000000ff, pickle.EXT1)  # largest EXT1 code

    def test_global_ext2(self):
        self.produce_global_ext(0x00000100, pickle.EXT2)  # smallest EXT2 code
        self.produce_global_ext(0x0000ffff, pickle.EXT2)  # largest EXT2 code
        self.produce_global_ext(0x0000abcd, pickle.EXT2)  # check endianness

    def test_global_ext4(self):
        self.produce_global_ext(0x00010000, pickle.EXT4)  # smallest EXT4 code
        self.produce_global_ext(0x7fffffff, pickle.EXT4)  # largest EXT4 code
        self.produce_global_ext(0x12abcdef, pickle.EXT4)  # check endianness

    def test_list_chunking(self):
        n = 10  # too small to chunk
        x = list(range(n))
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            num_appends = count_opcode(pickle.APPENDS, s)
            self.assertEqual(num_appends, proto > 0)

        n = 2500  # expect at least two chunks when proto > 0
        x = list(range(n))
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            num_appends = count_opcode(pickle.APPENDS, s)
            if proto == 0:
                self.assertEqual(num_appends, 0)
            else:
                self.assertTrue(num_appends >= 2)

    def test_dict_chunking(self):
        n = 10  # too small to chunk
        x = dict.fromkeys(range(n))
        for proto in protocols:
            s = self.dumps(x, proto)
            self.assertIsInstance(s, bytes_types)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            num_setitems = count_opcode(pickle.SETITEMS, s)
            self.assertEqual(num_setitems, proto > 0)

        n = 2500  # expect at least two chunks when proto > 0
        x = dict.fromkeys(range(n))
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            num_setitems = count_opcode(pickle.SETITEMS, s)
            if proto == 0:
                self.assertEqual(num_setitems, 0)
            else:
                self.assertTrue(num_setitems >= 2)

    def test_set_chunking(self):
        n = 10  # too small to chunk
        x = set(range(n))
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            num_additems = count_opcode(pickle.ADDITEMS, s)
            if proto < 4:
                self.assertEqual(num_additems, 0)
            else:
                self.assertEqual(num_additems, 1)

        n = 2500  # expect at least two chunks when proto >= 4
        x = set(range(n))
        for proto in protocols:
            s = self.dumps(x, proto)
            y = self.loads(s)
            self.assert_is_copy(x, y)
            num_additems = count_opcode(pickle.ADDITEMS, s)
            if proto < 4:
                self.assertEqual(num_additems, 0)
            else:
                self.assertGreaterEqual(num_additems, 2)

    def test_simple_newobj(self):
        x = SimpleNewObj.__new__(SimpleNewObj, 0xface)  # avoid __init__
        x.abc = 666
        for proto in protocols:
            with self.subTest(proto=proto):
                s = self.dumps(x, proto)
                if proto < 1:
                    self.assertIn(b'\nI64206', s)  # INT
                else:
                    self.assertIn(b'M\xce\xfa', s)  # BININT2
                self.assertEqual(opcode_in_pickle(pickle.NEWOBJ, s),
                                 2 <= proto)
                self.assertFalse(opcode_in_pickle(pickle.NEWOBJ_EX, s))
                y = self.loads(s)   # will raise TypeError if __init__ called
                self.assert_is_copy(x, y)

    def test_complex_newobj(self):
        x = ComplexNewObj.__new__(ComplexNewObj, 0xface)  # avoid __init__
        x.abc = 666
        for proto in protocols:
            with self.subTest(proto=proto):
                s = self.dumps(x, proto)
                if proto < 1:
                    self.assertIn(b'\nI64206', s)  # INT
                elif proto < 2:
                    self.assertIn(b'M\xce\xfa', s)  # BININT2
                elif proto < 4:
                    self.assertIn(b'X\x04\x00\x00\x00FACE', s)  # BINUNICODE
                else:
                    self.assertIn(b'\x8c\x04FACE', s)  # SHORT_BINUNICODE
                self.assertEqual(opcode_in_pickle(pickle.NEWOBJ, s),
                                 2 <= proto)
                self.assertFalse(opcode_in_pickle(pickle.NEWOBJ_EX, s))
                y = self.loads(s)   # will raise TypeError if __init__ called
                self.assert_is_copy(x, y)

    def test_complex_newobj_ex(self):
        x = ComplexNewObjEx.__new__(ComplexNewObjEx, 0xface)  # avoid __init__
        x.abc = 666
        for proto in protocols:
            with self.subTest(proto=proto):
                s = self.dumps(x, proto)
                if proto < 1:
                    self.assertIn(b'\nI64206', s)  # INT
                elif proto < 2:
                    self.assertIn(b'M\xce\xfa', s)  # BININT2
                elif proto < 4:
                    self.assertIn(b'X\x04\x00\x00\x00FACE', s)  # BINUNICODE
                else:
                    self.assertIn(b'\x8c\x04FACE', s)  # SHORT_BINUNICODE
                self.assertFalse(opcode_in_pickle(pickle.NEWOBJ, s))
                self.assertEqual(opcode_in_pickle(pickle.NEWOBJ_EX, s),
                                 4 <= proto)
                y = self.loads(s)   # will raise TypeError if __init__ called
                self.assert_is_copy(x, y)

    def test_newobj_list_slots(self):
        x = SlotList([1, 2, 3])
        x.foo = 42
        x.bar = "hello"
        s = self.dumps(x, 2)
        y = self.loads(s)
        self.assert_is_copy(x, y)

    def test_reduce_overrides_default_reduce_ex(self):
        for proto in protocols:
            x = REX_one()
            self.assertEqual(x._reduce_called, 0)
            s = self.dumps(x, proto)
            self.assertEqual(x._reduce_called, 1)
            y = self.loads(s)
            self.assertEqual(y._reduce_called, 0)

    def test_reduce_ex_called(self):
        for proto in protocols:
            x = REX_two()
            self.assertEqual(x._proto, None)
            s = self.dumps(x, proto)
            self.assertEqual(x._proto, proto)
            y = self.loads(s)
            self.assertEqual(y._proto, None)

    def test_reduce_ex_overrides_reduce(self):
        for proto in protocols:
            x = REX_three()
            self.assertEqual(x._proto, None)
            s = self.dumps(x, proto)
            self.assertEqual(x._proto, proto)
            y = self.loads(s)
            self.assertEqual(y._proto, None)

    def test_reduce_ex_calls_base(self):
        for proto in protocols:
            x = REX_four()
            self.assertEqual(x._proto, None)
            s = self.dumps(x, proto)
            self.assertEqual(x._proto, proto)
            y = self.loads(s)
            self.assertEqual(y._proto, proto)

    def test_reduce_calls_base(self):
        for proto in protocols:
            x = REX_five()
            self.assertEqual(x._reduce_called, 0)
            s = self.dumps(x, proto)
            self.assertEqual(x._reduce_called, 1)
            y = self.loads(s)
            self.assertEqual(y._reduce_called, 1)

    @no_tracing
    def test_bad_getattr(self):
        # Issue #3514: crash when there is an infinite loop in __getattr__
        x = BadGetattr()
        for proto in protocols:
            self.assertRaises(RuntimeError, self.dumps, x, proto)

    def test_reduce_bad_iterator(self):
        # Issue4176: crash when 4th and 5th items of __reduce__()
        # are not iterators
        class C(object):
            def __reduce__(self):
                # 4th item is not an iterator
                return list, (), None, [], None
        class D(object):
            def __reduce__(self):
                # 5th item is not an iterator
                return dict, (), None, None, []

        # Python implementation is less strict and also accepts iterables.
        for proto in protocols:
            try:
                self.dumps(C(), proto)
            except pickle.PicklingError:
                pass
            try:
                self.dumps(D(), proto)
            except pickle.PicklingError:
                pass

    def test_many_puts_and_gets(self):
        # Test that internal data structures correctly deal with lots of
        # puts/gets.
        keys = ("aaa" + str(i) for i in range(100))
        large_dict = dict((k, [4, 5, 6]) for k in keys)
        obj = [dict(large_dict), dict(large_dict), dict(large_dict)]

        for proto in protocols:
            with self.subTest(proto=proto):
                dumped = self.dumps(obj, proto)
                loaded = self.loads(dumped)
                self.assert_is_copy(obj, loaded)

    def test_attribute_name_interning(self):
        # Test that attribute names of pickled objects are interned when
        # unpickling.
        for proto in protocols:
            x = C()
            x.foo = 42
            x.bar = "hello"
            s = self.dumps(x, proto)
            y = self.loads(s)
            x_keys = sorted(x.__dict__)
            y_keys = sorted(y.__dict__)
            for x_key, y_key in zip(x_keys, y_keys):
                self.assertIs(x_key, y_key)

    def test_pickle_to_2x(self):
        # Pickle non-trivial data with protocol 2, expecting that it yields
        # the same result as Python 2.x did.
        # NOTE: this test is a bit too strong since we can produce different
        # bytecode that 2.x will still understand.
        dumped = self.dumps(range(5), 2)
        self.assertEqual(dumped, DATA_XRANGE)
        dumped = self.dumps(set([3]), 2)
        self.assertEqual(dumped, DATA_SET2)

    def test_large_pickles(self):
        # Test the correctness of internal buffering routines when handling
        # large data.
        for proto in protocols:
            data = (1, min, b'xy' * (30 * 1024), len)
            dumped = self.dumps(data, proto)
            loaded = self.loads(dumped)
            self.assertEqual(len(loaded), len(data))
            self.assertEqual(loaded, data)

    def test_int_pickling_efficiency(self):
        # Test compacity of int representation (see issue #12744)
        for proto in protocols:
            with self.subTest(proto=proto):
                pickles = [self.dumps(2**n, proto) for n in range(70)]
                sizes = list(map(len, pickles))
                # the size function is monotonic
                self.assertEqual(sorted(sizes), sizes)
                if proto >= 2:
                    for p in pickles:
                        self.assertFalse(opcode_in_pickle(pickle.LONG, p))

    def _check_pickling_with_opcode(self, obj, opcode, proto):
        pickled = self.dumps(obj, proto)
        self.assertTrue(opcode_in_pickle(opcode, pickled))
        unpickled = self.loads(pickled)
        self.assertEqual(obj, unpickled)

    def test_appends_on_non_lists(self):
        # Issue #17720
        obj = REX_six([1, 2, 3])
        for proto in protocols:
            if proto == 0:
                self._check_pickling_with_opcode(obj, pickle.APPEND, proto)
            else:
                self._check_pickling_with_opcode(obj, pickle.APPENDS, proto)

    def test_setitems_on_non_dicts(self):
        obj = REX_seven({1: -1, 2: -2, 3: -3})
        for proto in protocols:
            if proto == 0:
                self._check_pickling_with_opcode(obj, pickle.SETITEM, proto)
            else:
                self._check_pickling_with_opcode(obj, pickle.SETITEMS, proto)

    # Exercise framing (proto >= 4) for significant workloads

    FRAME_SIZE_MIN = 4
    FRAME_SIZE_TARGET = 64 * 1024

    def check_frame_opcodes(self, pickled):
        """
        Check the arguments of FRAME opcodes in a protocol 4+ pickle.

        Note that binary objects that are larger than FRAME_SIZE_TARGET are not
        framed by default and are therefore considered a frame by themselves in
        the following consistency check.
        """
        frame_end = frameless_start = None
        frameless_opcodes = {'BINBYTES', 'BINUNICODE', 'BINBYTES8',
                             'BINUNICODE8', 'BYTEARRAY8'}
        for op, arg, pos in pickletools.genops(pickled):
            if frame_end is not None:
                self.assertLessEqual(pos, frame_end)
                if pos == frame_end:
                    frame_end = None

            if frame_end is not None:  # framed
                self.assertNotEqual(op.name, 'FRAME')
                if op.name in frameless_opcodes:
                    # Only short bytes and str objects should be written
                    # in a frame
                    self.assertLessEqual(len(arg), self.FRAME_SIZE_TARGET)

            else:  # not framed
                if (op.name == 'FRAME' or
                    (op.name in frameless_opcodes and
                     len(arg) > self.FRAME_SIZE_TARGET)):
                    # Frame or large bytes or str object
                    if frameless_start is not None:
                        # Only short data should be written outside of a frame
                        self.assertLess(pos - frameless_start,
                                        self.FRAME_SIZE_MIN)
                        frameless_start = None
                elif frameless_start is None and op.name != 'PROTO':
                    frameless_start = pos

            if op.name == 'FRAME':
                self.assertGreaterEqual(arg, self.FRAME_SIZE_MIN)
                frame_end = pos + 9 + arg

        pos = len(pickled)
        if frame_end is not None:
            self.assertEqual(frame_end, pos)
        elif frameless_start is not None:
            self.assertLess(pos - frameless_start, self.FRAME_SIZE_MIN)

    def test_framing_many_objects(self):
        obj = list(range(10**5))
        for proto in range(4, pickle.HIGHEST_PROTOCOL + 1):
            with self.subTest(proto=proto):
                pickled = self.dumps(obj, proto)
                unpickled = self.loads(pickled)
                self.assertEqual(obj, unpickled)
                bytes_per_frame = (len(pickled) /
                                   count_opcode(pickle.FRAME, pickled))
                self.assertGreater(bytes_per_frame,
                                   self.FRAME_SIZE_TARGET / 2)
                self.assertLessEqual(bytes_per_frame,
                                     self.FRAME_SIZE_TARGET * 1)
                self.check_frame_opcodes(pickled)

    def test_framing_large_objects(self):
        N = 1024 * 1024
        small_items = [[i] for i in range(10)]
        obj = [b'x' * N, *small_items, b'y' * N, 'z' * N]
        for proto in range(4, pickle.HIGHEST_PROTOCOL + 1):
            for fast in [False, True]:
                with self.subTest(proto=proto, fast=fast):
                    if not fast:
                        # fast=False by default.
                        # This covers in-memory pickling with pickle.dumps().
                        pickled = self.dumps(obj, proto)
                    else:
                        # Pickler is required when fast=True.
                        if not hasattr(self, 'pickler'):
                            continue
                        buf = io.BytesIO()
                        pickler = self.pickler(buf, protocol=proto)
                        pickler.fast = fast
                        pickler.dump(obj)
                        pickled = buf.getvalue()
                    unpickled = self.loads(pickled)
                    # More informative error message in case of failure.
                    self.assertEqual([len(x) for x in obj],
                                     [len(x) for x in unpickled])
                    # Perform full equality check if the lengths match.
                    self.assertEqual(obj, unpickled)
                    n_frames = count_opcode(pickle.FRAME, pickled)
                    # A single frame for small objects between
                    # first two large objects.
                    self.assertEqual(n_frames, 1)
                    self.check_frame_opcodes(pickled)

    def test_optional_frames(self):
        if pickle.HIGHEST_PROTOCOL < 4:
            return

        def remove_frames(pickled, keep_frame=None):
            """Remove frame opcodes from the given pickle."""
            frame_starts = []
            # 1 byte for the opcode and 8 for the argument
            frame_opcode_size = 9
            for opcode, _, pos in pickletools.genops(pickled):
                if opcode.name == 'FRAME':
                    frame_starts.append(pos)

            newpickle = bytearray()
            last_frame_end = 0
            for i, pos in enumerate(frame_starts):
                if keep_frame and keep_frame(i):
                    continue
                newpickle += pickled[last_frame_end:pos]
                last_frame_end = pos + frame_opcode_size
            newpickle += pickled[last_frame_end:]
            return newpickle

        frame_size = self.FRAME_SIZE_TARGET
        num_frames = 20
        # Large byte objects (dict values) intermitted with small objects
        # (dict keys)
        for bytes_type in (bytes, bytearray):
            obj = {i: bytes_type([i]) * frame_size for i in range(num_frames)}

            for proto in range(4, pickle.HIGHEST_PROTOCOL + 1):
                pickled = self.dumps(obj, proto)

                frameless_pickle = remove_frames(pickled)
                self.assertEqual(count_opcode(pickle.FRAME, frameless_pickle), 0)
                self.assertEqual(obj, self.loads(frameless_pickle))

                some_frames_pickle = remove_frames(pickled, lambda i: i % 2)
                self.assertLess(count_opcode(pickle.FRAME, some_frames_pickle),
                                count_opcode(pickle.FRAME, pickled))
                self.assertEqual(obj, self.loads(some_frames_pickle))

    def test_framed_write_sizes_with_delayed_writer(self):
        class ChunkAccumulator:
            """Accumulate pickler output in a list of raw chunks."""
            def __init__(self):
                self.chunks = []
            def write(self, chunk):
                self.chunks.append(chunk)
            def concatenate_chunks(self):
                return b"".join(self.chunks)

        for proto in range(4, pickle.HIGHEST_PROTOCOL + 1):
            objects = [(str(i).encode('ascii'), i % 42, {'i': str(i)})
                       for i in range(int(1e4))]
            # Add a large unique ASCII string
            objects.append('0123456789abcdef' *
                           (self.FRAME_SIZE_TARGET // 16 + 1))

            # Protocol 4 packs groups of small objects into frames and issues
            # calls to write only once or twice per frame:
            # The C pickler issues one call to write per-frame (header and
            # contents) while Python pickler issues two calls to write: one for
            # the frame header and one for the frame binary contents.
            writer = ChunkAccumulator()
            self.pickler(writer, proto).dump(objects)

            # Actually read the binary content of the chunks after the end
            # of the call to dump: any memoryview passed to write should not
            # be released otherwise this delayed access would not be possible.
            pickled = writer.concatenate_chunks()
            reconstructed = self.loads(pickled)
            self.assertEqual(reconstructed, objects)
            self.assertGreater(len(writer.chunks), 1)

            # memoryviews should own the memory.
            del objects
            support.gc_collect()
            self.assertEqual(writer.concatenate_chunks(), pickled)

            n_frames = (len(pickled) - 1) // self.FRAME_SIZE_TARGET + 1
            # There should be at least one call to write per frame
            self.assertGreaterEqual(len(writer.chunks), n_frames)

            # but not too many either: there can be one for the proto,
            # one per-frame header, one per frame for the actual contents,
            # and two for the header.
            self.assertLessEqual(len(writer.chunks), 2 * n_frames + 3)

            chunk_sizes = [len(c) for c in writer.chunks]
            large_sizes = [s for s in chunk_sizes
                           if s >= self.FRAME_SIZE_TARGET]
            medium_sizes = [s for s in chunk_sizes
                           if 9 < s < self.FRAME_SIZE_TARGET]
            small_sizes = [s for s in chunk_sizes if s <= 9]

            # Large chunks should not be too large:
            for chunk_size in large_sizes:
                self.assertLess(chunk_size, 2 * self.FRAME_SIZE_TARGET,
                                chunk_sizes)
            # There shouldn't bee too many small chunks: the protocol header,
            # the frame headers and the large string headers are written
            # in small chunks.
            self.assertLessEqual(len(small_sizes),
                                 len(large_sizes) + len(medium_sizes) + 3,
                                 chunk_sizes)

    def test_nested_names(self):
        global Nested
        class Nested:
            class A:
                class B:
                    class C:
                        pass
        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
            for obj in [Nested.A, Nested.A.B, Nested.A.B.C]:
                with self.subTest(proto=proto, obj=obj):
                    unpickled = self.loads(self.dumps(obj, proto))
                    self.assertIs(obj, unpickled)

    def test_recursive_nested_names(self):
        global Recursive
        class Recursive:
            pass
        Recursive.mod = sys.modules[Recursive.__module__]
        Recursive.__qualname__ = 'Recursive.mod.Recursive'
        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
            with self.subTest(proto=proto):
                unpickled = self.loads(self.dumps(Recursive, proto))
                self.assertIs(unpickled, Recursive)
        del Recursive.mod # break reference loop

    def test_py_methods(self):
        global PyMethodsTest
        class PyMethodsTest:
            @staticmethod
            def cheese():
                return "cheese"
            @classmethod
            def wine(cls):
                assert cls is PyMethodsTest
                return "wine"
            def biscuits(self):
                assert isinstance(self, PyMethodsTest)
                return "biscuits"
            class Nested:
                "Nested class"
                @staticmethod
                def ketchup():
                    return "ketchup"
                @classmethod
                def maple(cls):
                    assert cls is PyMethodsTest.Nested
                    return "maple"
                def pie(self):
                    assert isinstance(self, PyMethodsTest.Nested)
                    return "pie"

        py_methods = (
            PyMethodsTest.cheese,
            PyMethodsTest.wine,
            PyMethodsTest().biscuits,
            PyMethodsTest.Nested.ketchup,
            PyMethodsTest.Nested.maple,
            PyMethodsTest.Nested().pie
        )
        py_unbound_methods = (
            (PyMethodsTest.biscuits, PyMethodsTest),
            (PyMethodsTest.Nested.pie, PyMethodsTest.Nested)
        )
        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
            for method in py_methods:
                with self.subTest(proto=proto, method=method):
                    unpickled = self.loads(self.dumps(method, proto))
                    self.assertEqual(method(), unpickled())
            for method, cls in py_unbound_methods:
                obj = cls()
                with self.subTest(proto=proto, method=method):
                    unpickled = self.loads(self.dumps(method, proto))
                    self.assertEqual(method(obj), unpickled(obj))

    def test_c_methods(self):
        global Subclass
        class Subclass(tuple):
            class Nested(str):
                pass

        c_methods = (
            # bound built-in method
            ("abcd".index, ("c",)),
            # unbound built-in method
            (str.index, ("abcd", "c")),
            # bound "slot" method
            ([1, 2, 3].__len__, ()),
            # unbound "slot" method
            (list.__len__, ([1, 2, 3],)),
            # bound "coexist" method
            ({1, 2}.__contains__, (2,)),
            # unbound "coexist" method
            (set.__contains__, ({1, 2}, 2)),
            # built-in class method
            (dict.fromkeys, (("a", 1), ("b", 2))),
            # built-in static method
            (bytearray.maketrans, (b"abc", b"xyz")),
            # subclass methods
            (Subclass([1,2,2]).count, (2,)),
            (Subclass.count, (Subclass([1,2,2]), 2)),
            (Subclass.Nested("sweet").count, ("e",)),
            (Subclass.Nested.count, (Subclass.Nested("sweet"), "e")),
        )
        for proto in range(pickle.HIGHEST_PROTOCOL + 1):
            for method, args in c_methods:
                with self.subTest(proto=proto, method=method):
                    unpickled = self.loads(self.dumps(method, proto))
                    self.assertEqual(method(*args), unpickled(*args))

    def test_compat_pickle(self):
        tests = [
            (range(1, 7), '__builtin__', 'xrange'),
            (map(int, '123'), 'itertools', 'imap'),
            (functools.reduce, '__builtin__', 'reduce'),
            (dbm.whichdb, 'whichdb', 'whichdb'),
            (Exception(), 'exceptions', 'Exception'),
            (collections.UserDict(), 'UserDict', 'IterableUserDict'),
            (collections.UserList(), 'UserList', 'UserList'),
            (collections.defaultdict(), 'collections', 'defaultdict'),
        ]
        for val, mod, name in tests:
            for proto in range(3):
                with self.subTest(type=type(val), proto=proto):
                    pickled = self.dumps(val, proto)
                    self.assertIn(('c%s\n%s' % (mod, name)).encode(), pickled)
                    self.assertIs(type(self.loads(pickled)), type(val))

    def test_local_lookup_error(self):
        # Test that whichmodule() errors out cleanly when looking up
        # an assumed globally-reachable object fails.
        def f():
            pass
        # Since the function is local, lookup will fail
        for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
            with self.assertRaises((AttributeError, pickle.PicklingError)):
                pickletools.dis(self.dumps(f, proto))
        # Same without a __module__ attribute (exercises a different path
        # in _pickle.c).
        del f.__module__
        for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
            with self.assertRaises((AttributeError, pickle.PicklingError)):
                pickletools.dis(self.dumps(f, proto))
        # Yet a different path.
        f.__name__ = f.__qualname__
        for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
            with self.assertRaises((AttributeError, pickle.PicklingError)):
                pickletools.dis(self.dumps(f, proto))

    def test_in_band_buffers(self):
        # Test in-band buffers (PEP 574)
        for obj, readonly in [(ZeroCopyBytes(b"foo"), True),
                              (ZeroCopyBytearray(b"foo"), False),
                              ]:
            for proto in range(0, pickle.HIGHEST_PROTOCOL + 1):
                data = self.dumps(obj, proto)
                self.assertIn(b"foo", data)
                self.assertEqual(count_opcode(pickle.NEXT_BUFFER, data), 0)
                if proto >= 5:
                    self.assertEqual(count_opcode(pickle.SHORT_BINBYTES, data),
                                     1 if readonly else 0)
                    self.assertEqual(count_opcode(pickle.BYTEARRAY8, data),
                                     0 if readonly else 1)
                    # Return a true value from buffer_callback should have
                    # the same effect
                    def buffer_callback(obj):
                        return True
                    data2 = self.dumps(obj, proto,
                                       buffer_callback=buffer_callback)
                    self.assertEqual(data2, data)

                new = self.loads(data)
                # It's a copy
                self.assertIsNot(new, obj)
                self.assertIs(type(new), type(obj))
                self.assertEqual(new, obj)

    def test_oob_buffers(self):
        # Test out-of-band buffers (PEP 574)
        for obj, readonly in [(ZeroCopyBytes(b"foo"), True),
                              (ZeroCopyBytearray(b"foo"), False),
                              ]:
            for proto in range(0, 5):
                # Need protocol >= 5 for buffer_callback
                with self.assertRaises(ValueError):
                    self.dumps(obj, proto,
                               buffer_callback=[].append)
            for proto in range(5, pickle.HIGHEST_PROTOCOL + 1):
                buffers = []
                buffer_callback = buffers.append
                data = self.dumps(obj, proto,
                                  buffer_callback=buffer_callback)
                self.assertNotIn(b"foo", data)
                self.assertEqual(count_opcode(pickle.SHORT_BINBYTES, data), 0)
                self.assertEqual(count_opcode(pickle.BYTEARRAY8, data), 0)
                self.assertEqual(count_opcode(pickle.NEXT_BUFFER, data), 1)
                self.assertEqual(count_opcode(pickle.READONLY_BUFFER, data),
                                 1 if readonly else 0)

                self.assertEqual(bytes(buffers[0]), b"foo")
                # Need buffers argument to unpickle properly
                with self.assertRaises(pickle.UnpicklingError):
                    self.loads(data)
                # Zero-copy achieved
                new = self.loads(data, buffers=buffers)
                self.assertIs(new, obj)
                # Non-sequence buffers accepted too
                new = self.loads(data, buffers=iter(buffers))
                self.assertIs(new, obj)

    def test_oob_buffers_writable_to_readonly(self):
        # Test reconstructing readonly object from writable buffer
        obj = ZeroCopyBytes(b"foo")
        for proto in range(5, pickle.HIGHEST_PROTOCOL + 1):
            buffers = []
            buffer_callback = buffers.append
            data = self.dumps(obj, proto, buffer_callback=buffer_callback)

            buffers = map(bytearray, buffers)
            new = self.loads(data, buffers=buffers)
            self.assertIs(type(new), type(obj))
            self.assertEqual(new, obj)

    def test_picklebuffer_error(self):
        # PickleBuffer forbidden with protocol < 5
        pb = pickle.PickleBuffer(b"foo")
        for proto in range(0, 5):
            with self.assertRaises(pickle.PickleError):
                self.dumps(pb, proto)

    def test_buffer_callback_error(self):
        def buffer_callback(buffers):
            1/0
        pb = pickle.PickleBuffer(b"foo")
        with self.assertRaises(ZeroDivisionError):
            self.dumps(pb, 5, buffer_callback=buffer_callback)

    def test_buffers_error(self):
        pb = pickle.PickleBuffer(b"foo")
        for proto in range(5, pickle.HIGHEST_PROTOCOL + 1):
            data = self.dumps(pb, proto, buffer_callback=[].append)
            # Non iterable buffers
            with self.assertRaises(TypeError):
                self.loads(data, buffers=object())
            # Buffer iterable exhausts too early
            with self.assertRaises(pickle.UnpicklingError):
                self.loads(data, buffers=[])


class BigmemPickleTests(unittest.TestCase):

    # Binary protocols can serialize longs of up to 2 GiB-1

    @bigmemtest(size=_2G, memuse=3.6, dry_run=False)
    def test_huge_long_32b(self, size):
        data = 1 << (8 * size)
        try:
            for proto in protocols:
                if proto < 2:
                    continue
                with self.subTest(proto=proto):
                    with self.assertRaises((ValueError, OverflowError)):
                        self.dumps(data, protocol=proto)
        finally:
            data = None

    # Protocol 3 can serialize up to 4 GiB-1 as a bytes object
    # (older protocols don't have a dedicated opcode for bytes and are
    # too inefficient)

    @bigmemtest(size=_2G, memuse=2.5, dry_run=False)
    def test_huge_bytes_32b(self, size):
        data = b"abcd" * (size // 4)
        try:
            for proto in protocols:
                if proto < 3:
                    continue
                with self.subTest(proto=proto):
                    try:
                        pickled = self.dumps(data, protocol=proto)
                        header = (pickle.BINBYTES +
                                  struct.pack("<I", len(data)))
                        data_start = pickled.index(data)
                        self.assertEqual(
                            header,
                            pickled[data_start-len(header):data_start])
                    finally:
                        pickled = None
        finally:
            data = None

    @bigmemtest(size=_4G, memuse=2.5, dry_run=False)
    def test_huge_bytes_64b(self, size):
        data = b"acbd" * (size // 4)
        try:
            for proto in protocols:
                if proto < 3:
                    continue
                with self.subTest(proto=proto):
                    if proto == 3:
                        # Protocol 3 does not support large bytes objects.
                        # Verify that we do not crash when processing one.
                        with self.assertRaises((ValueError, OverflowError)):
                            self.dumps(data, protocol=proto)
                        continue
                    try:
                        pickled = self.dumps(data, protocol=proto)
                        header = (pickle.BINBYTES8 +
                                  struct.pack("<Q", len(data)))
                        data_start = pickled.index(data)
                        self.assertEqual(
                            header,
                            pickled[data_start-len(header):data_start])
                    finally:
                        pickled = None
        finally:
            data = None

    # All protocols use 1-byte per printable ASCII character; we add another
    # byte because the encoded form has to be copied into the internal buffer.

    @bigmemtest(size=_2G, memuse=8, dry_run=False)
    def test_huge_str_32b(self, size):
        data = "abcd" * (size // 4)
        try:
            for proto in protocols:
                if proto == 0:
                    continue
                with self.subTest(proto=proto):
                    try:
                        pickled = self.dumps(data, protocol=proto)
                        header = (pickle.BINUNICODE +
                                  struct.pack("<I", len(data)))
                        data_start = pickled.index(b'abcd')
                        self.assertEqual(
                            header,
                            pickled[data_start-len(header):data_start])
                        self.assertEqual((pickled.rindex(b"abcd") + len(b"abcd") -
                                          pickled.index(b"abcd")), len(data))
                    finally:
                        pickled = None
        finally:
            data = None

    # BINUNICODE (protocols 1, 2 and 3) cannot carry more than 2**32 - 1 bytes
    # of utf-8 encoded unicode. BINUNICODE8 (protocol 4) supports these huge
    # unicode strings however.

    @bigmemtest(size=_4G, memuse=8, dry_run=False)
    def test_huge_str_64b(self, size):
        data = "abcd" * (size // 4)
        try:
            for proto in protocols:
                if proto == 0:
                    continue
                with self.subTest(proto=proto):
                    if proto < 4:
                        with self.assertRaises((ValueError, OverflowError)):
                            self.dumps(data, protocol=proto)
                        continue
                    try:
                        pickled = self.dumps(data, protocol=proto)
                        header = (pickle.BINUNICODE8 +
                                  struct.pack("<Q", len(data)))
                        data_start = pickled.index(b'abcd')
                        self.assertEqual(
                            header,
                            pickled[data_start-len(header):data_start])
                        self.assertEqual((pickled.rindex(b"abcd") + len(b"abcd") -
                                          pickled.index(b"abcd")), len(data))
                    finally:
                        pickled = None
        finally:
            data = None


# Test classes for reduce_ex

class REX_one(object):
    """No __reduce_ex__ here, but inheriting it from object"""
    _reduce_called = 0
    def __reduce__(self):
        self._reduce_called = 1
        return REX_one, ()

class REX_two(object):
    """No __reduce__ here, but inheriting it from object"""
    _proto = None
    def __reduce_ex__(self, proto):
        self._proto = proto
        return REX_two, ()

class REX_three(object):
    _proto = None
    def __reduce_ex__(self, proto):
        self._proto = proto
        return REX_two, ()
    def __reduce__(self):
        raise TestFailed("This __reduce__ shouldn't be called")

class REX_four(object):
    """Calling base class method should succeed"""
    _proto = None
    def __reduce_ex__(self, proto):
        self._proto = proto
        return object.__reduce_ex__(self, proto)

class REX_five(object):
    """This one used to fail with infinite recursion"""
    _reduce_called = 0
    def __reduce__(self):
        self._reduce_called = 1
        return object.__reduce__(self)

class REX_six(object):
    """This class is used to check the 4th argument (list iterator) of
    the reduce protocol.
    """
    def __init__(self, items=None):
        self.items = items if items is not None else []
    def __eq__(self, other):
        return type(self) is type(other) and self.items == other.items
    def append(self, item):
        self.items.append(item)
    def __reduce__(self):
        return type(self), (), None, iter(self.items), None

class REX_seven(object):
    """This class is used to check the 5th argument (dict iterator) of
    the reduce protocol.
    """
    def __init__(self, table=None):
        self.table = table if table is not None else {}
    def __eq__(self, other):
        return type(self) is type(other) and self.table == other.table
    def __setitem__(self, key, value):
        self.table[key] = value
    def __reduce__(self):
        return type(self), (), None, None, iter(self.table.items())


# Test classes for newobj

class MyInt(int):
    sample = 1

class MyFloat(float):
    sample = 1.0

class MyComplex(complex):
    sample = 1.0 + 0.0j

class MyStr(str):
    sample = "hello"

class MyUnicode(str):
    sample = "hello \u1234"

class MyTuple(tuple):
    sample = (1, 2, 3)

class MyList(list):
    sample = [1, 2, 3]

class MyDict(dict):
    sample = {"a": 1, "b": 2}

class MySet(set):
    sample = {"a", "b"}

class MyFrozenSet(frozenset):
    sample = frozenset({"a", "b"})

myclasses = [MyInt, MyFloat,
             MyComplex,
             MyStr, MyUnicode,
             MyTuple, MyList, MyDict, MySet, MyFrozenSet]


class SlotList(MyList):
    __slots__ = ["foo"]

class SimpleNewObj(int):
    def __init__(self, *args, **kwargs):
        # raise an error, to make sure this isn't called
        raise TypeError("SimpleNewObj.__init__() didn't expect to get called")
    def __eq__(self, other):
        return int(self) == int(other) and self.__dict__ == other.__dict__

class ComplexNewObj(SimpleNewObj):
    def __getnewargs__(self):
        return ('%X' % self, 16)

class ComplexNewObjEx(SimpleNewObj):
    def __getnewargs_ex__(self):
        return ('%X' % self,), {'base': 16}

class BadGetattr:
    def __getattr__(self, key):
        self.foo


class AbstractPickleModuleTests(unittest.TestCase):

    def test_dump_closed_file(self):
        import os
        f = open(TESTFN, "wb")
        try:
            f.close()
            self.assertRaises(ValueError, self.dump, 123, f)
        finally:
            os.remove(TESTFN)

    def test_load_closed_file(self):
        import os
        f = open(TESTFN, "wb")
        try:
            f.close()
            self.assertRaises(ValueError, self.dump, 123, f)
        finally:
            os.remove(TESTFN)

    def test_load_from_and_dump_to_file(self):
        stream = io.BytesIO()
        data = [123, {}, 124]
        self.dump(data, stream)
        stream.seek(0)
        unpickled = self.load(stream)
        self.assertEqual(unpickled, data)

    def test_highest_protocol(self):
        # Of course this needs to be changed when HIGHEST_PROTOCOL changes.
        self.assertEqual(pickle.HIGHEST_PROTOCOL, 5)

    def test_callapi(self):
        f = io.BytesIO()
        # With and without keyword arguments
        self.dump(123, f, -1)
        self.dump(123, file=f, protocol=-1)
        self.dumps(123, -1)
        self.dumps(123, protocol=-1)
        self.Pickler(f, -1)
        self.Pickler(f, protocol=-1)

    def test_bad_init(self):
        # Test issue3664 (pickle can segfault from a badly initialized Pickler).
        # Override initialization without calling __init__() of the superclass.
        class BadPickler(self.Pickler):
            def __init__(self): pass

        class BadUnpickler(self.Unpickler):
            def __init__(self): pass

        self.assertRaises(pickle.PicklingError, BadPickler().dump, 0)
        self.assertRaises(pickle.UnpicklingError, BadUnpickler().load)

    def check_dumps_loads_oob_buffers(self, dumps, loads):
        # No need to do the full gamut of tests here, just enough to
        # check that dumps() and loads() redirect their arguments
        # to the underlying Pickler and Unpickler, respectively.
        obj = ZeroCopyBytes(b"foo")

        for proto in range(0, 5):
            # Need protocol >= 5 for buffer_callback
            with self.assertRaises(ValueError):
                dumps(obj, protocol=proto,
                      buffer_callback=[].append)
        for proto in range(5, pickle.HIGHEST_PROTOCOL + 1):
            buffers = []
            buffer_callback = buffers.append
            data = dumps(obj, protocol=proto,
                         buffer_callback=buffer_callback)
            self.assertNotIn(b"foo", data)
            self.assertEqual(bytes(buffers[0]), b"foo")
            # Need buffers argument to unpickle properly
            with self.assertRaises(pickle.UnpicklingError):
                loads(data)
            new = loads(data, buffers=buffers)
            self.assertIs(new, obj)

    def test_dumps_loads_oob_buffers(self):
        # Test out-of-band buffers (PEP 574) with top-level dumps() and loads()
        self.check_dumps_loads_oob_buffers(self.dumps, self.loads)

    def test_dump_load_oob_buffers(self):
        # Test out-of-band buffers (PEP 574) with top-level dump() and load()
        def dumps(obj, **kwargs):
            f = io.BytesIO()
            self.dump(obj, f, **kwargs)
            return f.getvalue()

        def loads(data, **kwargs):
            f = io.BytesIO(data)
            return self.load(f, **kwargs)

        self.check_dumps_loads_oob_buffers(dumps, loads)


class AbstractPersistentPicklerTests(unittest.TestCase):

    # This class defines persistent_id() and persistent_load()
    # functions that should be used by the pickler.  All even integers
    # are pickled using persistent ids.

    def persistent_id(self, object):
        if isinstance(object, int) and object % 2 == 0:
            self.id_count += 1
            return str(object)
        elif object == "test_false_value":
            self.false_count += 1
            return ""
        else:
            return None

    def persistent_load(self, oid):
        if not oid:
            self.load_false_count += 1
            return "test_false_value"
        else:
            self.load_count += 1
            object = int(oid)
            assert object % 2 == 0
            return object

    def test_persistence(self):
        L = list(range(10)) + ["test_false_value"]
        for proto in protocols:
            self.id_count = 0
            self.false_count = 0
            self.load_false_count = 0
            self.load_count = 0
            self.assertEqual(self.loads(self.dumps(L, proto)), L)
            self.assertEqual(self.id_count, 5)
            self.assertEqual(self.false_count, 1)
            self.assertEqual(self.load_count, 5)
            self.assertEqual(self.load_false_count, 1)


class AbstractIdentityPersistentPicklerTests(unittest.TestCase):

    def persistent_id(self, obj):
        return obj

    def persistent_load(self, pid):
        return pid

    def _check_return_correct_type(self, obj, proto):
        unpickled = self.loads(self.dumps(obj, proto))
        self.assertIsInstance(unpickled, type(obj))
        self.assertEqual(unpickled, obj)

    def test_return_correct_type(self):
        for proto in protocols:
            # Protocol 0 supports only ASCII strings.
            if proto == 0:
                self._check_return_correct_type("abc", 0)
            else:
                for obj in [b"abc\n", "abc\n", -1, -1.1 * 0.1, str]:
                    self._check_return_correct_type(obj, proto)

    def test_protocol0_is_ascii_only(self):
        non_ascii_str = "\N{EMPTY SET}"
        self.assertRaises(pickle.PicklingError, self.dumps, non_ascii_str, 0)
        pickled = pickle.PERSID + non_ascii_str.encode('utf-8') + b'\n.'
        self.assertRaises(pickle.UnpicklingError, self.loads, pickled)


class AbstractPicklerUnpicklerObjectTests(unittest.TestCase):

    pickler_class = None
    unpickler_class = None

    def setUp(self):
        assert self.pickler_class
        assert self.unpickler_class

    def test_clear_pickler_memo(self):
        # To test whether clear_memo() has any effect, we pickle an object,
        # then pickle it again without clearing the memo; the two serialized
        # forms should be different. If we clear_memo() and then pickle the
        # object again, the third serialized form should be identical to the
        # first one we obtained.
        data = ["abcdefg", "abcdefg", 44]
        for proto in protocols:
            f = io.BytesIO()
            pickler = self.pickler_class(f, proto)

            pickler.dump(data)
            first_pickled = f.getvalue()

            # Reset BytesIO object.
            f.seek(0)
            f.truncate()

            pickler.dump(data)
            second_pickled = f.getvalue()

            # Reset the Pickler and BytesIO objects.
            pickler.clear_memo()
            f.seek(0)
            f.truncate()

            pickler.dump(data)
            third_pickled = f.getvalue()

            self.assertNotEqual(first_pickled, second_pickled)
            self.assertEqual(first_pickled, third_pickled)

    def test_priming_pickler_memo(self):
        # Verify that we can set the Pickler's memo attribute.
        data = ["abcdefg", "abcdefg", 44]
        f = io.BytesIO()
        pickler = self.pickler_class(f)

        pickler.dump(data)
        first_pickled = f.getvalue()

        f = io.BytesIO()
        primed = self.pickler_class(f)
        primed.memo = pickler.memo

        primed.dump(data)
        primed_pickled = f.getvalue()

        self.assertNotEqual(first_pickled, primed_pickled)

    def test_priming_unpickler_memo(self):
        # Verify that we can set the Unpickler's memo attribute.
        data = ["abcdefg", "abcdefg", 44]
        f = io.BytesIO()
        pickler = self.pickler_class(f)

        pickler.dump(data)
        first_pickled = f.getvalue()

        f = io.BytesIO()
        primed = self.pickler_class(f)
        primed.memo = pickler.memo

        primed.dump(data)
        primed_pickled = f.getvalue()

        unpickler = self.unpickler_class(io.BytesIO(first_pickled))
        unpickled_data1 = unpickler.load()

        self.assertEqual(unpickled_data1, data)

        primed = self.unpickler_class(io.BytesIO(primed_pickled))
        primed.memo = unpickler.memo
        unpickled_data2 = primed.load()

        primed.memo.clear()

        self.assertEqual(unpickled_data2, data)
        self.assertTrue(unpickled_data2 is unpickled_data1)

    def test_reusing_unpickler_objects(self):
        data1 = ["abcdefg", "abcdefg", 44]
        f = io.BytesIO()
        pickler = self.pickler_class(f)
        pickler.dump(data1)
        pickled1 = f.getvalue()

        data2 = ["abcdefg", 44, 44]
        f = io.BytesIO()
        pickler = self.pickler_class(f)
        pickler.dump(data2)
        pickled2 = f.getvalue()

        f = io.BytesIO()
        f.write(pickled1)
        f.seek(0)
        unpickler = self.unpickler_class(f)
        self.assertEqual(unpickler.load(), data1)

        f.seek(0)
        f.truncate()
        f.write(pickled2)
        f.seek(0)
        self.assertEqual(unpickler.load(), data2)

    def _check_multiple_unpicklings(self, ioclass):
        for proto in protocols:
            with self.subTest(proto=proto):
                data1 = [(x, str(x)) for x in range(2000)] + [b"abcde", len]
                f = ioclass()
                pickler = self.pickler_class(f, protocol=proto)
                pickler.dump(data1)
                pickled = f.getvalue()

                N = 5
                f = ioclass(pickled * N)
                unpickler = self.unpickler_class(f)
                for i in range(N):
                    if f.seekable():
                        pos = f.tell()
                    self.assertEqual(unpickler.load(), data1)
                    if f.seekable():
                        self.assertEqual(f.tell(), pos + len(pickled))
                self.assertRaises(EOFError, unpickler.load)

    def test_multiple_unpicklings_seekable(self):
        self._check_multiple_unpicklings(io.BytesIO)

    def test_multiple_unpicklings_unseekable(self):
        self._check_multiple_unpicklings(UnseekableIO)

    def test_unpickling_buffering_readline(self):
        # Issue #12687: the unpickler's buffering logic could fail with
        # text mode opcodes.
        data = list(range(10))
        for proto in protocols:
            for buf_size in range(1, 11):
                f = io.BufferedRandom(io.BytesIO(), buffer_size=buf_size)
                pickler = self.pickler_class(f, protocol=proto)
                pickler.dump(data)
                f.seek(0)
                unpickler = self.unpickler_class(f)
                self.assertEqual(unpickler.load(), data)

    def test_unpickling_trivial_io(self):
        # Check unpickling with an io class that doesn't have readinto()
        sizes = [1, 16, 1000, 2**10]
        data = [(b"x" * size, bytearray(b"x") * size) for size in sizes]
        for proto in protocols:
            with self.subTest(proto=proto):
                bio = io.BytesIO()
                pickler = self.pickler_class(bio, protocol=proto)
                pickler.dump(data)
                N = 5
                f = TrivialReadableIO(bio.getvalue() * N)
                unpickler = self.unpickler_class(f)
                for i in range(N):
                    self.assertEqual(unpickler.load(), data)
                self.assertRaises(EOFError, unpickler.load)


# Tests for dispatch_table attribute

REDUCE_A = 'reduce_A'

class AAA(object):
    def __reduce__(self):
        return str, (REDUCE_A,)

class BBB(object):
    pass

class AbstractDispatchTableTests(unittest.TestCase):

    def test_default_dispatch_table(self):
        # No dispatch_table attribute by default
        f = io.BytesIO()
        p = self.pickler_class(f, 0)
        with self.assertRaises(AttributeError):
            p.dispatch_table
        self.assertFalse(hasattr(p, 'dispatch_table'))

    def test_class_dispatch_table(self):
        # A dispatch_table attribute can be specified class-wide
        dt = self.get_dispatch_table()

        class MyPickler(self.pickler_class):
            dispatch_table = dt

        def dumps(obj, protocol=None):
            f = io.BytesIO()
            p = MyPickler(f, protocol)
            self.assertEqual(p.dispatch_table, dt)
            p.dump(obj)
            return f.getvalue()

        self._test_dispatch_table(dumps, dt)

    def test_instance_dispatch_table(self):
        # A dispatch_table attribute can also be specified instance-wide
        dt = self.get_dispatch_table()

        def dumps(obj, protocol=None):
            f = io.BytesIO()
            p = self.pickler_class(f, protocol)
            p.dispatch_table = dt
            self.assertEqual(p.dispatch_table, dt)
            p.dump(obj)
            return f.getvalue()

        self._test_dispatch_table(dumps, dt)

    def _test_dispatch_table(self, dumps, dispatch_table):
        def custom_load_dump(obj):
            return pickle.loads(dumps(obj, 0))

        def default_load_dump(obj):
            return pickle.loads(pickle.dumps(obj, 0))

        # pickling complex numbers using protocol 0 relies on copyreg
        # so check pickling a complex number still works
        z = 1 + 2j
        self.assertEqual(custom_load_dump(z), z)
        self.assertEqual(default_load_dump(z), z)

        # modify pickling of complex
        REDUCE_1 = 'reduce_1'
        def reduce_1(obj):
            return str, (REDUCE_1,)
        dispatch_table[complex] = reduce_1
        self.assertEqual(custom_load_dump(z), REDUCE_1)
        self.assertEqual(default_load_dump(z), z)

        # check picklability of AAA and BBB
        a = AAA()
        b = BBB()
        self.assertEqual(custom_load_dump(a), REDUCE_A)
        self.assertIsInstance(custom_load_dump(b), BBB)
        self.assertEqual(default_load_dump(a), REDUCE_A)
        self.assertIsInstance(default_load_dump(b), BBB)

        # modify pickling of BBB
        dispatch_table[BBB] = reduce_1
        self.assertEqual(custom_load_dump(a), REDUCE_A)
        self.assertEqual(custom_load_dump(b), REDUCE_1)
        self.assertEqual(default_load_dump(a), REDUCE_A)
        self.assertIsInstance(default_load_dump(b), BBB)

        # revert pickling of BBB and modify pickling of AAA
        REDUCE_2 = 'reduce_2'
        def reduce_2(obj):
            return str, (REDUCE_2,)
        dispatch_table[AAA] = reduce_2
        del dispatch_table[BBB]
        self.assertEqual(custom_load_dump(a), REDUCE_2)
        self.assertIsInstance(custom_load_dump(b), BBB)
        self.assertEqual(default_load_dump(a), REDUCE_A)
        self.assertIsInstance(default_load_dump(b), BBB)


if __name__ == "__main__":
    # Print some stuff that can be used to rewrite DATA{0,1,2}
    from pickletools import dis
    x = create_data()
    for i in range(pickle.HIGHEST_PROTOCOL+1):
        p = pickle.dumps(x, i)
        print("DATA{0} = (".format(i))
        for j in range(0, len(p), 20):
            b = bytes(p[j:j+20])
            print("    {0!r}".format(b))
        print(")")
        print()
        print("# Disassembly of DATA{0}".format(i))
        print("DATA{0}_DIS = \"\"\"\\".format(i))
        dis(p)
        print("\"\"\"")
        print()
