Update build_targets tests

Author: YingboMa

test/build_targets.jl

@@ -8,8 +8,8 @@ eqs = [D(x) ~ a*x - x*y,
     """
     real[] diffeqf(real t,real[] internal_var___u,real[] internal_var___p,real[] x_r,int[] x_i) {
       real internal_var___du[2];
-      internal_var___du[1] = internal_var___p[1] * internal_var___u[1] - internal_var___u[1] * internal_var___u[2];
-      internal_var___du[2] = -3 * internal_var___u[2] + internal_var___u[1] * internal_var___u[2];
+      internal_var___du[1] = internal_var___p[1] * internal_var___u[1] + -1 * internal_var___u[1] * internal_var___u[2];
+      internal_var___du[2] = internal_var___u[1] * internal_var___u[2] + -3 * internal_var___u[2];
       return internal_var___du;
     }
     """
@@ -19,14 +19,14 @@ eqs = [D(x) ~ a*x - x*y,
                                      rhsnames=[:internal_var___u,:internal_var___p,:t]) ==
   """
   void diffeqf(double* internal_var___du, double* internal_var___u, double* internal_var___p, double t) {
-    internal_var___du[0] = internal_var___p[0] * internal_var___u[0] - internal_var___u[0] * internal_var___u[1];
-    internal_var___du[1] = -3 * internal_var___u[1] + internal_var___u[0] * internal_var___u[1];
+    internal_var___du[0] = internal_var___p[0] * internal_var___u[0] + -1 * internal_var___u[0] * internal_var___u[1];
+    internal_var___du[1] = internal_var___u[0] * internal_var___u[1] + -3 * internal_var___u[1];
   }
   """
 
 @test ModelingToolkit.build_function(eqs,[x,y],[a],t,target = ModelingToolkit.MATLABTarget()) ==
   """
-  diffeqf = @(t,internal_var___u) [internal_var___p(1) * internal_var___u(1) - internal_var___u(1) * internal_var___u(2); -3 * internal_var___u(2) + internal_var___u(1) * internal_var___u(2)];"""
+  diffeqf = @(t,internal_var___u) [internal_var___p(1) * internal_var___u(1) + -1 * internal_var___u(1) * internal_var___u(2); internal_var___u(1) * internal_var___u(2) + -3 * internal_var___u(2)];"""
 
 sys = ODESystem(eqs,t,[x,y],[a])