def test_shift_monomial_past_end(self):
"""Test that shifting a Monomial beyond 0 yields 0."""
m1 = Monomial(1, 10) >> 15
m2 = Monomial(1, 10) << -15
m0 = Monomial.zero_instance()
self._assert_polynomials_are_the_same(m0, m1)
self._assert_polynomials_are_the_same(m0, m2)
def test_zero_instance_mutable(self):
"""Test that zero instances are mutable."""
zp = Polynomial.zero_instance()
zm = Monomial.zero_instance()
zc = Constant.zero_instance()
zp.a = 1
zm.a = 1
zc.const = 1
self._assert_polynomials_are_the_same(Polynomial(1), zp)
self._assert_polynomials_are_the_same(Monomial(1, 0), zm)
self._assert_polynomials_are_the_same(Constant(1), zc)