text: from sympy.integrals.singularityfunctions import singularityintegrate
  from sympy import SingularityFunction, symbols, Function
  
  x, a, n, y = symbols('x a n y')
  f = Function('f')
  
  
  def test_singularityintegrate():
      assert singularityintegrate(x, x) is None
      assert singularityintegrate(x + SingularityFunction(x, 9, 1), x) is None
  
      assert 4*singularityintegrate(SingularityFunction(x, a, 3), x) == 4*SingularityFunction(x, a, 4)/4
      assert singularityintegrate(5*SingularityFunction(x, 5, -2), x) == 5*SingularityFunction(x, 5, -1)
      assert singularityintegrate(6*SingularityFunction(x, 5, -1), x) == 6*SingularityFunction(x, 5, 0)
      assert singularityintegrate(x*SingularityFunction(x, 0, -1), x) == 0
      assert singularityintegrate((x - 5)*SingularityFunction(x, 5, -1), x) == 0
      assert singularityintegrate(SingularityFunction(x, 0, -1) * f(x), x) == f(0) * SingularityFunction(x, 0, 0)
      assert singularityintegrate(SingularityFunction(x, 1, -1) * f(x), x) == f(1) * SingularityFunction(x, 1, 0)
      assert singularityintegrate(y*SingularityFunction(x, 0, -1)**2, x) == \
          y*SingularityFunction(0, 0, -1)*SingularityFunction(x, 0, 0)
  