Add chemistry in symmetry test

tests/testSymmetry.c

@@ -47,6 +47,15 @@ int main(int argc, char *argv[]) {
     *(((float *)&pj) + i) = (float)random_uniform(0., 2.);
   }
 
+  /* Create a chemistry structure */
+  struct chemistry_data chemistry;
+  /* At one point, we will need to initialize the chemistry
+  chemistry_init(const struct swift_params* parameter_file,
+		 const struct unit_system* us,
+		 const struct phys_const* phys_const,
+		 &chemistry);
+  */
+  
   /* Make the particle smoothing length and position reasonable */
   for (size_t i = 0; i < 3; ++i) pi.x[0] = random_uniform(-1., 1.);
   for (size_t i = 0; i < 3; ++i) pj.x[0] = random_uniform(-1., 1.);
@@ -137,13 +146,19 @@ int main(int argc, char *argv[]) {
 
   /* Call the symmetric version */
   runner_iact_density(r2, dx, pi.h, pj.h, &pi, &pj);
+  /* Now the chemistry. WARNING chemistry is not initialized */
+  runner_iact_chemistry(r2, dx, pi.h, pj.h, &pi, &pj, &chemistry);
 
   /* Call the non-symmetric version */
   runner_iact_nonsym_density(r2, dx, pi2.h, pj2.h, &pi2, &pj2);
+  /* Now the chemistry. WARNING chemistry is not initialized */
+  runner_iact_nonsym_chemistry(r2, dx, pi2.h, pj2.h, &pi2, &pj2, &chemistry);
   dx[0] = -dx[0];
   dx[1] = -dx[1];
   dx[2] = -dx[2];
   runner_iact_nonsym_density(r2, dx, pj2.h, pi2.h, &pj2, &pi2);
+  /* Now the chemistry. WARNING chemistry is not initialized */
+  runner_iact_nonsym_chemistry(r2, dx, pj2.h, pi2.h, &pj2, &pi2, &chemistry);
 
   /* Check that the particles are the same */
   i_ok = memcmp(&pi, &pi2, sizeof(struct part));