prepare error messages in sde sims

Author: TorkelE

test/model_simulation/simulate_SDEs.jl

@@ -300,10 +300,18 @@ let
     ps = [:p => 1000.0, :d => 1.0, :η1 => 1.0, :η2 => 1.4, :η3 => 0.33, :η4 => 4.0]
     sprob = SDEProblem(noise_scaling_network, u0, (0.0, 1000.0), ps)
 
+    # Test have at some point failed due to StochasticDiffEq failing to initiate. This temporary extra
+    # check is in place if it will happen again, to help us investigate.
     for repeat in 1:5
-        sol = solve(sprob, ImplicitEM(); saveat = 1.0, adaptive = false, dt = 0.01, seed = rand(rng, 1:100))
-        SciMLBase.successful_retcode(sol) || continue
-        @test var(sol[:X1]) > var(sol[:X2]) > var(sol[:X3]) > var(sol[:X4]) > var(sol[:X5])
+        seed = rand(rng, 1:100)
+        sol = solve(sprob, ImplicitEM(); seed, saveat = 1.0, adaptive = false, dt = 0.01)
+        if SciMLBase.successful_retcode(sol)
+            @test var(sol[:X1]) > var(sol[:X2]) > var(sol[:X3]) > var(sol[:X4]) > var(sol[:X5])
+        else
+            println("Problem with SDE simulation test (fails but should not).")
+            println("Seed: $seed")
+            println("Retcode: $(sol.retcode)")
+        end
     end
 end