def METHOD_NAME(mesh):
    # test function space
    v = FunctionSpace(mesh, "DG", 1)
    # Create limiter
    limiter = VertexBasedLimiter(v)
    # Set up constant field
    u0 = Constant(1)
    u = Function(v).interpolate(u0)
    u_old = Function(u)
    limiter.apply(u)
    diff = assemble(inner(u - u_old, u - u_old) * dx) ** 0.5
    assert diff < 1.0e-10, "Failed on Constant function"