def test_exp(self):
t = SymbolSet('t', [
('bra_open', '('),
('bra_close', ')'),
('add', '+'),
('mul', '*'),
'id',
])
nt = SymbolSet('nt', [
('value', 'V'),
('exp', 'E'),
('product', 'P'),
('start', 'S'),
])
rules = [
CFGRule(nt.value, (t.id,)),
CFGRule(nt.value, (t.bra_open, nt.exp, t.bra_close)),
CFGRule(nt.product, (nt.value,)),
CFGRule(nt.product, (nt.product, t.mul, nt.value)),
CFGRule(nt.exp, (nt.product,)),
CFGRule(nt.exp, (nt.exp, t.add, nt.product)),
CFGRule(nt.start, (nt.exp,)),
]
identity = lambda x: x
reductions = [
Reduction(rules[0], lambda x1: float(x1)),
Reduction(rules[1], lambda x1, x2, x3: x2),
Reduction(rules[2], identity),
Reduction(rules[3], lambda x1, x2, x3: x1 * x3),
Reduction(rules[4], identity),
Reduction(rules[5], lambda x1, x2, x3: x1 + x3),
Reduction(rules[6], identity),
]
cfgex = CFGExtended(nt, t, reductions, nt.start)
slr_gen = SLRStateGenerator(cfgex)
lr_gen = LRStateGenerator(cfgex)
slr_action_table, slr_transition_table, slr_debug_info = slr_gen.generate_tables()
lr_action_table, lr_transition_table, lr_debug_info = lr_gen.generate_tables()
slr_parser = LRParser(slr_action_table, slr_transition_table,
initial_state=0,
debug_info=slr_debug_info)
lr_parser = LRParser(lr_action_table, lr_transition_table,
initial_state=0,
debug_info=lr_debug_info)
#self.dump_action_table(action_table, debug_info)
for parser in [slr_parser, lr_parser]:
tokens = [
Token(t.bra_open),
Token(t.id, 1),
Token(t.bra_close),
]
result = parser.parse(tokens)
self.assertEqual(result, 1)
tokens = [
Token(t.id, 2),
Token(t.add),
Token(t.id, 2),
]
result = parser.parse(tokens)
self.assertEqual(result, 4)
tokens = [
Token(t.id, 2),
Token(t.add),
Token(t.id, 2),
Token(t.mul),
Token(t.id, 2),
]
result = parser.parse(tokens)
self.assertEqual(result, 6)
tokens = [
Token(t.id, 2),
Token(t.add),
Token(t.bra_open),
Token(t.id, 2),
Token(t.mul),
Token(t.id, 2),
Token(t.bra_close),
]
result = parser.parse(tokens)
self.assertEqual(result, 6)
tokens = [
Token(t.bra_open),
Token(t.id, 2),
Token(t.add),
Token(t.id, 2),
Token(t.bra_close),
Token(t.mul),
Token(t.id, 2),
]
result = parser.parse(tokens)
self.assertEqual(result, 8)
tokens = [
Token(t.bra_open),
Token(t.bra_open),
Token(t.id, 2),
Token(t.add),
Token(t.id, 3),
Token(t.bra_close),
Token(t.mul),
Token(t.bra_open),
Token(t.id, 7),
Token(t.add),
Token(t.id, 11),
Token(t.bra_close),
Token(t.bra_close),
]
result = parser.parse(tokens)
self.assertEqual(result, (2 + 3) * (7 + 11))
def test_exp_slr(self):
t = SymbolSet('t', [
('bra_open', '('),
('bra_close', ')'),
('add', '+'),
('mul', '*'),
'id',
])
nt = SymbolSet('nt', [
('value', 'V'),
('exp', 'E'),
('product', 'P'),
('start', 'S'),
])
rules = [
CFGRule(nt.value, (t.id,)),
CFGRule(nt.value, (t.bra_open, nt.exp, t.bra_close)),
CFGRule(nt.product, (nt.value,)),
CFGRule(nt.product, (nt.product, t.mul, nt.value)),
CFGRule(nt.exp, (nt.product,)),
CFGRule(nt.exp, (nt.exp, t.add, nt.product)),
CFGRule(nt.start, (nt.exp,)),
]
cfg = CFG(nt, t, rules, nt.start)
start_rule = rules[6]
start_situation = SLRSituationState(start_rule.head_symbol,
(), start_rule.body_symbols)
s0 = SLRState(cfg, [start_situation])
cmp1_s0 = SLRState(cfg, [
SLRSituationState(nt.start, (), (nt.exp,)),
SLRSituationState(nt.exp, (), (nt.exp, t.add, nt.product)),
SLRSituationState(nt.exp, (), (nt.product,)),
SLRSituationState(nt.product, (), (nt.product, t.mul, nt.value)),
SLRSituationState(nt.product, (), (nt.value,)),
SLRSituationState(nt.value, (), (t.bra_open, nt.exp, t.bra_close)),
SLRSituationState(nt.value, (), (t.id,)),
])
cmp2_s0 = SLRState(cfg, [
SLRSituationState(nt.start, (), (nt.exp,)),
SLRSituationState(nt.exp, (nt.exp,), (t.add, nt.product)),
])
self.assertEqual(s0, cmp1_s0)
self.assertNotEqual(s0, cmp2_s0)
self.assertEqual(repr(s0)[:len('SLRState([')], 'SLRState([')
self.assertEqual(unicode(str(s0)), unicode(s0))
self.assertSetEqual(s0.actions, frozenset([
nt.exp, nt.product, nt.value,
t.id, t.bra_open
]))
for a in s0.actions:
next_states = s0.next_states(a)
self.assertEqual(len(next_states), 1)
gen = SLRStateGenerator(cfg)
action_table, transition_table, debug_info = gen.generate_tables()
self.assertEqual(len(action_table), 12)
self.assertEqual(len(transition_table), 12)
self.assertEqual(len(debug_info), 12)