github.com/grumpyhome/grumpy@v0.3.1-0.20201208125205-7b775405bdf1/grumpy-runtime-src/third_party/stdlib/test/test_tuple.py (about)

     1  from test import test_support, seq_tests
     2  
     3  # import gc
     4  
     5  class TupleTest(seq_tests.CommonTest):
     6      type2test = tuple
     7  
     8      def test_constructors(self):
     9          super(TupleTest, self).test_constructors()
    10          # calling built-in types without argument must return empty
    11          self.assertEqual(tuple(), ())
    12          t0_3 = (0, 1, 2, 3)
    13          t0_3_bis = tuple(t0_3)
    14          self.assertTrue(t0_3 is t0_3_bis)
    15          self.assertEqual(tuple([]), ())
    16          self.assertEqual(tuple([0, 1, 2, 3]), (0, 1, 2, 3))
    17          self.assertEqual(tuple(''), ())
    18          self.assertEqual(tuple('spam'), ('s', 'p', 'a', 'm'))
    19  
    20      def test_truth(self):
    21          super(TupleTest, self).test_truth()
    22          self.assertTrue(not ())
    23          self.assertTrue((42, ))
    24  
    25      def test_len(self):
    26          super(TupleTest, self).test_len()
    27          self.assertEqual(len(()), 0)
    28          self.assertEqual(len((0,)), 1)
    29          self.assertEqual(len((0, 1, 2)), 3)
    30  
    31      def test_iadd(self):
    32          super(TupleTest, self).test_iadd()
    33          u = (0, 1)
    34          u2 = u
    35          u += (2, 3)
    36          self.assertTrue(u is not u2)
    37  
    38      def test_imul(self):
    39          super(TupleTest, self).test_imul()
    40          u = (0, 1)
    41          u2 = u
    42          u *= 3
    43          self.assertTrue(u is not u2)
    44  
    45      def test_tupleresizebug(self):
    46          # Check that a specific bug in _PyTuple_Resize() is squashed.
    47          def f():
    48              for i in range(1000):
    49                  yield i
    50          self.assertEqual(list(tuple(f())), range(1000))
    51  
    52      def test_hash(self):
    53          # See SF bug 942952:  Weakness in tuple hash
    54          # The hash should:
    55          #      be non-commutative
    56          #      should spread-out closely spaced values
    57          #      should not exhibit cancellation in tuples like (x,(x,y))
    58          #      should be distinct from element hashes:  hash(x)!=hash((x,))
    59          # This test exercises those cases.
    60          # For a pure random hash and N=50, the expected number of occupied
    61          #      buckets when tossing 252,600 balls into 2**32 buckets
    62          #      is 252,592.6, or about 7.4 expected collisions.  The
    63          #      standard deviation is 2.73.  On a box with 64-bit hash
    64          #      codes, no collisions are expected.  Here we accept no
    65          #      more than 15 collisions.  Any worse and the hash function
    66          #      is sorely suspect.
    67  
    68          N=50
    69          base = range(N)
    70          xp = [(i, j) for i in base for j in base]
    71          inps = base + [(i, j) for i in base for j in xp] + \
    72                       [(i, j) for i in xp for j in base] + xp + zip(base)
    73          collisions = len(inps) - len(set(map(hash, inps)))
    74          self.assertTrue(collisions <= 15)
    75  
    76      def test_repr(self):
    77          l0 = tuple()
    78          l2 = (0, 1, 2)
    79          a0 = self.type2test(l0)
    80          a2 = self.type2test(l2)
    81  
    82          self.assertEqual(str(a0), repr(l0))
    83          self.assertEqual(str(a2), repr(l2))
    84          self.assertEqual(repr(a0), "()")
    85          self.assertEqual(repr(a2), "(0, 1, 2)")
    86  
    87      # def _not_tracked(self, t):
    88      #     # Nested tuples can take several collections to untrack
    89      #     gc.collect()
    90      #     gc.collect()
    91      #     self.assertFalse(gc.is_tracked(t), t)
    92  
    93      # def _tracked(self, t):
    94      #     self.assertTrue(gc.is_tracked(t), t)
    95      #     gc.collect()
    96      #     gc.collect()
    97      #     self.assertTrue(gc.is_tracked(t), t)
    98  
    99      # @test_support.cpython_only
   100      # def test_track_literals(self):
   101      #     # Test GC-optimization of tuple literals
   102      #     x, y, z = 1.5, "a", []
   103  
   104      #     self._not_tracked(())
   105      #     self._not_tracked((1,))
   106      #     self._not_tracked((1, 2))
   107      #     self._not_tracked((1, 2, "a"))
   108      #     self._not_tracked((1, 2, (None, True, False, ()), int))
   109      #     self._not_tracked((object(),))
   110      #     self._not_tracked(((1, x), y, (2, 3)))
   111  
   112      #     # Tuples with mutable elements are always tracked, even if those
   113      #     # elements are not tracked right now.
   114      #     self._tracked(([],))
   115      #     self._tracked(([1],))
   116      #     self._tracked(({},))
   117      #     self._tracked((set(),))
   118      #     self._tracked((x, y, z))
   119  
   120      # def check_track_dynamic(self, tp, always_track):
   121      #     x, y, z = 1.5, "a", []
   122  
   123      #     check = self._tracked if always_track else self._not_tracked
   124      #     check(tp())
   125      #     check(tp([]))
   126      #     check(tp(set()))
   127      #     check(tp([1, x, y]))
   128      #     check(tp(obj for obj in [1, x, y]))
   129      #     check(tp(set([1, x, y])))
   130      #     check(tp(tuple([obj]) for obj in [1, x, y]))
   131      #     check(tuple(tp([obj]) for obj in [1, x, y]))
   132  
   133      #     self._tracked(tp([z]))
   134      #     self._tracked(tp([[x, y]]))
   135      #     self._tracked(tp([{x: y}]))
   136      #     self._tracked(tp(obj for obj in [x, y, z]))
   137      #     self._tracked(tp(tuple([obj]) for obj in [x, y, z]))
   138      #     self._tracked(tuple(tp([obj]) for obj in [x, y, z]))
   139  
   140      # @test_support.cpython_only
   141      # def test_track_dynamic(self):
   142      #     # Test GC-optimization of dynamically constructed tuples.
   143      #     self.check_track_dynamic(tuple, False)
   144  
   145      # @test_support.cpython_only
   146      # def test_track_subtypes(self):
   147      #     # Tuple subtypes must always be tracked
   148      #     class MyTuple(tuple):
   149      #         pass
   150      #     self.check_track_dynamic(MyTuple, True)
   151  
   152      # @test_support.cpython_only
   153      # def test_bug7466(self):
   154      #     # Trying to untrack an unfinished tuple could crash Python
   155      #     self._not_tracked(tuple(gc.collect() for i in range(101)))
   156  
   157  def test_main():
   158      test_support.run_unittest(TupleTest)
   159  
   160  if __name__=="__main__":
   161      test_main()