def test_mux_enough_inputs_with_default(self):
        a = pyrtl.WireVector(name='a', bitwidth=3)
        b = pyrtl.WireVector(name='b', bitwidth=1)
        c = pyrtl.WireVector(name='c', bitwidth=1)
        d = pyrtl.WireVector(name='d', bitwidth=1)
        s = pyrtl.WireVector(name='s', bitwidth=2)
        r = pyrtl.corecircuits.mux(s, a, b, c, d, default=0)