test: fix SCCNonlinearProblem indexing test

test/downstream/problem_interface.jl

@@ -294,8 +294,6 @@ prob = SteadyStateProblem(osys, u0, ps)
       getsym(prob, (:X, :X2))(prob) == (0.1, 0.2)
 
 @testset "SCCNonlinearProblem" begin
-    # TODO: Rewrite this example when the MTK codegen is merged
-
     function fullf!(du, u, p)
         du[1] = cos(u[2]) - u[1]
         du[2] = sin(u[1] + u[2]) + u[2]
@@ -311,63 +309,10 @@ prob = SteadyStateProblem(osys, u0, ps)
     @parameters p = 1.0
     eqs = Any[0 for _ in 1:8]
     fullf!(eqs, u, [p])
-    @named model = NonlinearSystem(0 .~ eqs, [u...], [p])
-    model = complete(model; split = false)
-
-    cache = zeros(4)
-    cache[1] = 1.0
-
-    function f1!(du, u, p)
-        du[1] = cos(u[2]) - u[1]
-        du[2] = sin(u[1] + u[2]) + u[2]
-    end
-    explicitfun1(cache, sols) = nothing
-
-    f1!(eqs, u2[1:2], [p])
-    @named subsys1 = NonlinearSystem(0 .~ eqs[1:2], [u2[1:2]...], [p])
-    subsys1 = complete(subsys1; split = false)
-    prob1 = NonlinearProblem(
-        NonlinearFunction{true, SciMLBase.NoSpecialize}(f1!; sys = subsys1),
-        zeros(2), copy(cache))
-
-    function f2!(du, u, p)
-        du[1] = 2u[2] + u[1] + p[1]
-        du[2] = u[3]^2 + u[2]
-        du[3] = u[1]^2 + u[3]
-    end
-    explicitfun2(cache, sols) = nothing
-
-    f2!(eqs, u2[3:5], [p])
-    @named subsys2 = NonlinearSystem(0 .~ eqs[1:3], [u2[3:5]...], [p])
-    subsys2 = complete(subsys2; split = false)
-    prob2 = NonlinearProblem(
-        NonlinearFunction{true, SciMLBase.NoSpecialize}(f2!; sys = subsys2),
-        zeros(3), copy(cache))
-
-    function f3!(du, u, p)
-        du[1] = p[2] + 2.0u[1] + 2.5u[2] + 1.5u[3]
-        du[2] = p[3] + 4.0u[1] - 1.5u[2] + 1.5u[3]
-        du[3] = p[4] + +u[1] - u[2] - u[3]
-    end
-    function explicitfun3(cache, sols)
-        cache[2] = sols[1][1] + sols[1][2] + sols[2][1] + sols[2][2] + sols[2][3]
-        cache[3] = sols[1][1] + sols[1][2] + sols[2][1] + 2.0sols[2][2] + sols[2][3]
-        cache[4] = sols[1][1] + 2.0sols[1][2] + 3.0sols[2][1] + 5.0sols[2][2] +
-                   6.0sols[2][3]
-    end
-
-    @parameters tmpvar[1:3]
-    f3!(eqs, u2[6:8], [p, tmpvar...])
-    @named subsys3 = NonlinearSystem(0 .~ eqs[1:3], [u2[6:8]...], [p, tmpvar...])
-    subsys3 = complete(subsys3; split = false)
-    prob3 = NonlinearProblem(
-        NonlinearFunction{true, SciMLBase.NoSpecialize}(f3!; sys = subsys3),
-        zeros(3), copy(cache))
+    @mtkbuild model = NonlinearSystem(0 .~ eqs, [u...], [p])
 
     prob = NonlinearProblem(model, [])
-    sccprob = SciMLBase.SCCNonlinearProblem([prob1, prob2, prob3],
-        SciMLBase.Void{Any}.([explicitfun1, explicitfun2, explicitfun3]),
-        copy(cache); sys = model)
+    sccprob = SCCNonlinearProblem(model, [])
 
     for sym in [u, u..., u[2] + u[3], p * u[1] + u[2]]
         @test prob[sym] ≈ sccprob[sym]
@@ -380,12 +325,10 @@ prob = SteadyStateProblem(osys, u0, ps)
     for (i, sym) in enumerate([u[1], u[3], u[6]])
         sccprob[sym] = 0.5i
         @test sccprob[sym] ≈ 0.5i
-        @test sccprob.probs[i].u0[1] ≈ 0.5i
     end
     sccprob.ps[p] = 2.5
     @test sccprob.ps[p] ≈ 2.5
-    @test sccprob.p[1] ≈ 2.5
     for scc in sccprob.probs
-        @test parameter_values(scc)[1] ≈ 2.5
+        @test scc.ps[p] ≈ 2.5
     end
 end