def METHOD_NAME(self):
    element = VectorElement("CG", "triangle", 1)
    v  = TestFunction(element)
    u  = TrialFunction(element)
    # legal
    vv = as_vector(u[i], i)
    uu = as_vector(v[j], j)
    w  = v + u
    ww = vv + uu
    assert len(vv.ufl_shape) == 1
    assert len(uu.ufl_shape) == 1
    assert len(w.ufl_shape) == 1
    assert len(ww.ufl_shape) == 1