Using rostest with simulation time

edit

I have two problems in using rostest. it may be that it is not a specific question but both of them together could solve my problem:

1. How could I assure that nodes already have run when a certain test is running? For example I want to test my_node using file test_my_node. I write a .test file that run my_node and test test_my_node. But test file can run nodes in any order so it could be sometime that my_node currently does not start but the test runs and it fails.
2. When I set the use_sim_time true, anything does not work, no publisher subscriber runs and nothing happens. But when I start publishing on clock topic after some time other nodes run and start to publish and subscribe, this behavior is very odd to me.

In my real scenario I have a node and a nodelet which must run all together and after that a test_node must run to check something of them. I am using ros kinetic on ubuntu 16.04.