tests: fix linearize tests with default values

Author: ven-k

test/input_output_handling.jl

@@ -128,7 +128,9 @@ eqs = [connect(torque.flange, inertia1.flange_a)
        connect(inertia2.flange_a, spring.flange_b, damper.flange_b)
        y ~ inertia2.w + torque.tau.u]
 model = ODESystem(eqs, t; systems = [torque, inertia1, inertia2, spring, damper],
-    name = :name)
+    name = :name, defaults = Dict(
+        [torque.tau.u, inertia1.w, inertia2.w, inertia1.phi, inertia2.phi] .=> 0.0
+    ))
 model_outputs = [inertia1.w, inertia2.w, inertia1.phi, inertia2.phi]
 model_inputs = [torque.tau.u]
 matrices, ssys = linearize(model, model_inputs, model_outputs);

test/split_parameters.jl

@@ -154,9 +154,15 @@ function SystemModel(u = nothing; name = :model)
         push!(eqs, connect(torque.tau, u.output))
         return @named model = ODESystem(eqs,
             t;
-            systems = [torque, inertia1, inertia2, spring, damper, u])
+            systems = [torque, inertia1, inertia2, spring, damper, u],
+            defaults = Dict(
+                [torque.tau.u, inertia1.w, inertia2.w, inertia1.phi, inertia2.phi] .=> 0.0
+            ))
     end
-    ODESystem(eqs, t; systems = [torque, inertia1, inertia2, spring, damper], name)
+    ODESystem(eqs, t; systems = [torque, inertia1, inertia2, spring, damper], name,
+        defaults = Dict(
+            [torque.tau.u, inertia1.w, inertia2.w, inertia1.phi, inertia2.phi] .=> 0.0
+        ))
 end
 
 model = SystemModel() # Model with load disturbance