Weird Test-Functions on Triple Mixed Spaces

Dear all,

If I define a triple mixed function space, similar to a Taylor-Hood discretization but P2, P1, P2, e.g.

V2 = VectorElement("CG", mesh.ufl_cell(), 2)
S1 = FiniteElement("CG", mesh.ufl_cell(), 1)

TH2 = V2*S1*V2
F2 = FunctionSpace(mesh, TH2)
v = TestFunctions(F2)

I think it's natural to assume the Test Functions v should follow the components of V2, S1, V2, e.g. be a 3 component list consisting of (in 2D:)

1) 2 element UFL list tensor [[v_0[0], v_0[1]]
2) 1 UFL indexed v_0[2]
3) 2 element UFL list tensor [v_0[3], v_0[4]]

But in the current dev version, I am getting as a return a 2 component list consisting of

1) 3 element UFL list tensor [v_0[0], v_0[1], v_0[2]]
2) 2 element UFL list tensor [v_0[3], v_0[4]]

so, the test functions do not adhere the grouping of the desired function space, which seems rather weird.

As a consequence of this, the command

(u,q,w) = v.split()

seems no longer to be working...

A minimal example is attached.

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