1 # Python test set -- part 3, built-in operations.

     2 

     3 

     4 print '3. Operations'

     5 print 'XXX Mostly not yet implemented'

     6 

     7 

     8 print '3.1 Dictionary lookups fail if __cmp__() raises an exception'

     9 

    10 class BadDictKey:

    11 

    12     def __hash__(self):

    13         return hash(self.__class__)

    14 

    15     def __cmp__(self, other):

    16         if isinstance(other, self.__class__):

    17             print "raising error"

    18             raise RuntimeError, "gotcha"

    19         return other

    20 

    21 d = {}

    22 x1 = BadDictKey()

    23 x2 = BadDictKey()

    24 d[x1] = 1

    25 for stmt in ['d[x2] = 2',

    26              'z = d[x2]',

    27              'x2 in d',

    28              'd.has_key(x2)',

    29              'd.get(x2)',

    30              'd.setdefault(x2, 42)',

    31              'd.pop(x2)',

    32              'd.update({x2: 2})']:

    33     try:

    34         exec stmt

    35     except RuntimeError:

    36         print "%s: caught the RuntimeError outside" % (stmt,)

    37     else:

    38         print "%s: No exception passed through!"     # old CPython behavior

    39 

    40 

    41 # Dict resizing bug, found by Jack Jansen in 2.2 CVS development.

    42 # This version got an assert failure in debug build, infinite loop in

    43 # release build.  Unfortunately, provoking this kind of stuff requires

    44 # a mix of inserts and deletes hitting exactly the right hash codes in

    45 # exactly the right order, and I can't think of a randomized approach

    46 # that would be *likely* to hit a failing case in reasonable time.

    47 

    48 d = {}

    49 for i in range(5):

    50     d[i] = i

    51 for i in range(5):

    52     del d[i]

    53 for i in range(5, 9):  # i==8 was the problem

    54     d[i] = i

    55 

    56 

    57 # Another dict resizing bug (SF bug #1456209).

    58 # This caused Segmentation faults or Illegal instructions.

    59 

    60 class X(object):

    61     def __hash__(self):

    62         return 5

    63     def __eq__(self, other):

    64         if resizing:

    65             d.clear()

    66         return False

    67 d = {}

    68 resizing = False

    69 d[X()] = 1

    70 d[X()] = 2

    71 d[X()] = 3

    72 d[X()] = 4

    73 d[X()] = 5

    74 # now trigger a resize

    75 resizing = True

    76 d[9] = 6

    77 

    78 print 'resize bugs not triggered.'