Improved bisimulation test

tests/core/test_bisimulation.py

@@ -16,12 +16,18 @@ class TestBisimulation:
         assert model.nr_transitions == 13041
         assert model.model_type == stormpy.ModelType.DTMC
         assert not model.supports_parameters
-
-        model_bisim = stormpy.perform_bisimulation(model, properties[0], stormpy.BisimulationType.STRONG)
+        initial_state = model.initial_states[0]
+        assert initial_state == 0
+        result = stormpy.model_checking(model, properties[0])
+        model_bisim = stormpy.perform_bisimulation(model, properties, stormpy.BisimulationType.STRONG)
         assert model_bisim.nr_states == 64
         assert model_bisim.nr_transitions == 104
         assert model_bisim.model_type == stormpy.ModelType.DTMC
         assert not model_bisim.supports_parameters
+        result_bisim = stormpy.model_checking(model_bisim, properties[0])
+        initial_state_bisim = model_bisim.initial_states[0]
+        assert initial_state_bisim == 34
+        assert math.isclose(result.at(initial_state), result_bisim.at(initial_state_bisim), rel_tol=1e-4)
     
     def test_parametric_bisimulation(self):
         program = stormpy.parse_prism_program(get_example_path("pdtmc", "crowds3_5.pm"))