fix TransitionFocusOracle.py state tracking

Author: Edi Muskardin

aalpy/oracles/TransitionFocusOracle.py

@@ -31,7 +31,7 @@ def find_cex(self, hypothesis):
         for _ in range(self.num_walks):
             self.reset_hyp_and_sul(hypothesis)
 
-            curr_state = hypothesis.initial_state
+            curr_state = hypothesis.current_state
             inputs = []
             for _ in range(self.steps_per_walk):
                 if random.random() <= self.same_state_prob:
@@ -46,6 +46,8 @@ def find_cex(self, hypothesis):
                 out_hyp = hypothesis.step(inputs[-1])
                 self.num_steps += 1
 
+                curr_state = hypothesis.current_state
+
                 if out_sul != out_hyp:
                     self.sul.post()
                     return inputs