def test_frozen_zero_instance_immutable(self):
"""Test that FrozenPolynomial returns correct zero instance."""
fp = FrozenPolynomial(0)
fpz = FrozenPolynomial.zero_instance()
self._assert_polynomials_are_the_same(fp, fpz)
self.assertRaises(AttributeError, fpz.__setitem__, 0, 1)
self.assertRaises(AttributeError, fpz.__setattr__, "a", 1)
def test_frozen_polynomial_hash_equal(self):
"""Test that equal frozen polynomials have equal hash value."""
f1 = FrozenPolynomial(1, 2, 3)
f2 = FrozenPolynomial(f1)
h1 = hash(f1)
h2 = hash(f2)
self.assertEqual(h1, h2)
self.assertEqual({h1}, {h1, h2})
def test_frozen_polynomial_raises_err(self):
"""Test that a FrozenPolynomial raises errors when setting values."""
f = FrozenPolynomial(1, 2, 3)
self.assertRaises(AttributeError, f.__setattr__, "x", 5)
self.assertRaises(AttributeError, f.__setitem__, 0, 5)
self.assertRaises(AttributeError, f.__imul__, 5)
def test_zero_polynomial_hash_equal_to_empty_frozen_polynomal_hash(self):
"""Test that hash(ZeroPolynomial()) == hash(FrozenPolynomial())."""
z = ZeroPolynomial()
f = FrozenPolynomial()
hz = hash(z)
hf = hash(f)
self.assertEqual(hz, hf)
def test_frozen_vector_immutable(self):
"""Test that frozen vectors can't be modified."""
a = ZeroPolynomial()
b = FrozenPolynomial(1, 2, 3)
def set_item(obj, index, value):
obj[index] = value
possible_errs = (TypeError, AttributeError)
self.assertRaises(possible_errs, set_item, a._vector, 0, 5)
self.assertRaises(possible_errs, set_item, b._vector, 0, 5)
def test_casting_to_frozen_polynomial(self):
"""Casting polynomials is fine."""
a = Polynomial(1, 2, 3)
b = FrozenPolynomial.from_polynomial(a)
self.assertEqual(a, b)
def test_frozen(self):
"""Test that repr() output of a FrozenPolynomial is valid."""
expect = "FrozenPolynomial(1, 2, 3)"
r = repr(FrozenPolynomial(1, 2, 3))
self.assertEqual(expect, r)