def test_pda_intersection():
q0 = State("q0")
q1 = State("q1")
q2 = State("q2")
q3 = State("q3")
a = Symbol("a")
b = Symbol("b")
c = Symbol("c")
epsilon_nfa_1 = EpsilonNFA(states={q0, q1, q2},
input_symbols={a, b},
start_state={q0},
final_states={q1, q2})
epsilon_nfa_1.add_transition(q0, a, q1)
epsilon_nfa_1.add_transition(q1, b, q2)
epsilon_nfa_2 = EpsilonNFA(states={q0, q1, q3},
input_symbols={a, c},
start_state={q0},
final_states={q1, q3})
epsilon_nfa_2.add_transition(q0, a, q1)
epsilon_nfa_2.add_transition(q1, c, q3)
expected_epsilon_nfa = EpsilonNFA(states={q0, q1},
input_symbols={a},
start_state={q0},
final_states={q1})
expected_epsilon_nfa.add_transition(q0, a, q1)
actual_intersection = epsilon_nfa_1.get_intersection(epsilon_nfa_2)
assert expected_epsilon_nfa.is_equivalent_to(actual_intersection)
def test_check_intersection():
# Declare NFAs
enfa0 = EpsilonNFA()
enfa1 = EpsilonNFA()
# Declare the states
states = [State("q" + str(x)) for x in range(7)]
# Declare the symbols
epsilon = Epsilon()
symb_a = Symbol("a")
symb_b = Symbol("b")
symb_c = Symbol("c")
# epsilonNFA 0
# Add a start state
enfa0.add_start_state(states[0])
# Add a final state
enfa0.add_final_state(states[1])
# Add the transitions
enfa0.add_transition(states[0], symb_a, states[1])
enfa0.add_transition(states[1], symb_a, states[1])
# epsilonNFA 1
# Add a start states
enfa1.add_start_state(states[0])
enfa1.add_final_state(states[4])
# Add a final states
enfa1.add_final_state(states[5])
enfa1.add_final_state(states[6])
# Add the transitions
enfa1.add_transition(states[0], symb_a, states[1])
enfa1.add_transition(states[0], symb_b, states[2])
enfa1.add_transition(states[0], symb_c, states[3])
enfa1.add_transition(states[1], symb_a, states[4])
enfa1.add_transition(states[2], symb_b, states[5])
enfa1.add_transition(states[3], symb_c, states[6])
# Now enfa0 accepts a* \ {epsilon}
# enfa1 accepts aa, bb, cc
# Intersection of enfa0 and enfa1
enfa_res = enfa0.get_intersection(enfa1)
# Check if a word is accepted
assert enfa_res.accepts([symb_a, symb_a]), "Should accept aa"
# Check non-correct words
assert not enfa_res.accepts([epsilon]), "Accepts empty word, but it mustn't"
assert not enfa_res.accepts([symb_a, symb_a, symb_a]), "Accepts aaa, but it mustn't"
assert not enfa_res.accepts([symb_a]), "Accepts a, but it mustn't"
assert not enfa_res.accepts([symb_b, symb_b]), "Accepts bb, but it mustn't"
assert not enfa_res.accepts([symb_c, symb_c]), "Accepts cc, but it mustn't"