def test_intersection_regex(self):
""" Tests the intersection with a regex """
# pylint: disable=too-many-locals
state_p = State("p")
state_q = State("q")
state_r = State("r")
state_i = Symbol("i")
state_e = Symbol("e")
state_z = StackSymbol("Z")
state_x0 = StackSymbol("X0")
pda = PDA(states={state_p, state_q, state_r},
input_symbols={state_i, state_e},
stack_alphabet={state_z, state_x0},
start_state=state_p,
start_stack_symbol=state_x0,
final_states={state_r})
pda.add_transition(state_p, Epsilon(), state_x0, state_q,
[state_z, state_x0])
pda.add_transition(state_q, state_i, state_z, state_q,
[state_z, state_z])
pda.add_transition(state_q, state_e, state_z, state_q, [])
pda.add_transition(state_q, Epsilon(), state_x0, state_r, [])
state_s = finite_automaton.State("s")
state_t = finite_automaton.State("t")
i_dfa = finite_automaton.Symbol("i")
e_dfa = finite_automaton.Symbol("e")
dfa = finite_automaton.DeterministicFiniteAutomaton(
states={state_s, state_t},
input_symbols={i_dfa, e_dfa},
start_state=state_s,
final_states={state_s, state_t})
dfa.add_transition(state_s, i_dfa, state_s)
dfa.add_transition(state_s, e_dfa, state_t)
dfa.add_transition(state_t, e_dfa, state_t)
new_pda = pda.intersection(dfa)
pda_es = new_pda.to_empty_stack()
cfg = pda_es.to_cfg()
self.assertEqual(new_pda.get_number_transitions(), 6)
self.assertEqual(len(new_pda.states), 5)
self.assertEqual(len(new_pda.final_states), 2)
self.assertEqual(len(new_pda.input_symbols), 2)
self.assertEqual(len(new_pda.stack_symbols), 2)
i_cfg = Terminal("i")
e_cfg = Terminal("e")
self.assertTrue(cfg.contains([i_cfg, i_cfg, e_cfg, e_cfg, e_cfg]))
new_pda = pda.intersection(
finite_automaton.DeterministicFiniteAutomaton())
self.assertEqual(new_pda.get_number_transitions(), 0)
def _get_next_state_enfa(self):
s_final = finite_automaton.State(self._counter)
self._counter += 1
return s_final