def test_simple_production_union():
cfg = CFG([
("S", PUnion([PTerminal("foo"), PTerminal("bar")])),
])
expect = [("foo", ), ("bar", )]
result = list(cfg.permutation_values("S"))
assert expect == result
def test_coerce_features():
""" we should be able to coerce common feature descriptions. """
# string as value
assert PTerminal("foo", features={"num": "1"}).features == {"num": {"1"}}
# list as value
assert PTerminal("foo", features={
"num": ["1", "2"]
}).features == {
"num": {"1", "2"}
}
# coerce all else as strings.
assert PTerminal("foo", features={"num": 1}).features == {"num": {"1"}}
def test_full_example():
my_cfg = CFG([("PRONOUN", PTerminal("I")), ("VERB", PTerminal("have")),
("NOUN", PTerminal("candy")), ("NOUN", PTerminal("bonbons")),
("SENTENCE",
PList([PRef("PRONOUN"),
PRef("VERB"),
PRef("NOUN")]))])
result = set(my_cfg.permutation_values("SENTENCE"))
expect = set([
("I", "have", "candy"),
("I", "have", "bonbons"),
])
def test_feature_mismatch():
""" a feature mismatch should result """
my_cfg = CFG([("PRONOUN", PTerminal("I", features={"person": set("1")})),
("PRONOUN", PTerminal("You", features={"person": set("2")})),
("VERB", PTerminal("have", features={"person": set("2")})),
("NOUN", PTerminal("candy")),
("SENTENCE",
PList([PRef("PRONOUN"),
PRef("VERB"),
PRef("NOUN")]))])
result = set(my_cfg.permutation_values("SENTENCE"))
expect = set([("You", "have", "candy")])
assert result == expect
def test_passing_features(features, expected):
""" asking for a permutation with specific features should work. """
cfg = CFG([("S", PTerminal("I", features={"person": 1})),
("S", PTerminal("you", features={"person": 2})),
("S", PTerminal("he", features={
"person": 3,
"gender": "m"
})),
("S", PTerminal("she", features={
"person": 3,
"gender": "f"
}))])
print(expected)
print(set(cfg.permutation_values("S", features=features)))
assert set(cfg.permutation_values("S", features=features)) == expected
def test_simple_production_ref():
cfg = CFG([
("S", PTerminal("foo")),
])
expect = [("foo",)]
result = list(cfg.permutation_values(PRef("S")))
assert expect == result
def test_list_with_features():
"""
if a feature is passed into the list, it will only
accept a collected feature set that matches.
"""
cfg = CFG([("AB_UPPER",
PList([PRef("A"), PRef("B")], features={"case": "upper"})),
("AB_LOWER",
PList([PRef("A"), PRef("B")], features={"case": "lower"})),
("A",
PUnion([
PTerminal("a", features={"case": "lower"}),
PTerminal("A", features={"case": "upper"})
])),
("B",
PUnion([
PTerminal("b", features={"case": "lower"}),
PTerminal("B", features={"case": "upper"})
]))])
assert list(cfg.permutation_values("AB_UPPER")) == [("A", "B")]
assert list(cfg.permutation_values("AB_LOWER")) == [("a", "b")]
def test_equality():
assert (PList([PTerminal("foo"), PTerminal("bar")
]) == PList([PTerminal("foo"),
PTerminal("bar")]))
assert not (PList([PTerminal("foo"), PTerminal("bar")]) != PList(
[PTerminal("foo"), PTerminal("bar")]))
def test_multiple_productions_same_rule():
cfg = CFG([("S", PTerminal("foo")), ("S", PTerminal("bar"))])
result = cfg.permutation_values("S")
expect = [("foo", ), ("bar", )]
assert set(result) == set(expect)
def test_equality():
lhs = CFG([("S", PTerminal("foo")), ("S", PTerminal("bar"))])
rhs = CFG([("S", PTerminal("foo")), ("S", PTerminal("bar"))])
assert lhs == rhs
def test_equal():
assert (PTerminal("I",
features={"person":
"1"}) == PTerminal("I",
features={"person": "1"}))
def test_simple_terminal():
cfg = CFG([("S", PTerminal("foo"))])
assert list(cfg.permutation_values("S")) == [("foo", )]
def test_equality():
assert (PUnion([PTerminal("foo"), PTerminal("bar")
]) == PUnion([PTerminal("foo"),
PTerminal("bar")]))