def test_partial_constraint(polar):
class User:
pass
class Post:
pass
polar.register_class(User)
polar.register_class(Post)
polar.load_str("f(x: User) if x.user = 1;")
polar.load_str("f(x: Post) if x.post = 1;")
partial = Partial("x", TypeConstraint("User"))
results = polar.query_rule("f", partial)
first = next(results)["bindings"]["x"]
and_args = unwrap_and(first)
assert len(and_args) == 2
assert and_args[0] == Expression("Isa", [Variable("_this"), Pattern("User", {})])
unify = unwrap_and(and_args[1])
assert unify == Expression(
"Unify", [Expression("Dot", [Variable("_this"), "user"]), 1]
)
with pytest.raises(StopIteration):
next(results)
def test_dict_specializers(polar, qvar, qeval, query):
class Animal:
def __init__(self, species=None, genus=None, family=None):
self.genus = genus
self.species = species
polar.register_class(Animal)
rules = """
what_is(_: {genus: "canis"}, res) if res = "canine";
what_is(_: {species: "canis lupus", genus: "canis"}, res) if res = "wolf";
what_is(_: {species: "canis familiaris", genus: "canis"}, res) if res = "dog";
"""
polar.load_str(rules)
wolf = 'new Animal(species: "canis lupus", genus: "canis", family: "canidae")'
dog = 'new Animal(species: "canis familiaris", genus: "canis", family: "canidae")'
canine = 'new Animal(genus: "canis", family: "canidae")'
assert len(query(f"what_is({wolf}, res)")) == 2
assert len(query(f"what_is({dog}, res)")) == 2
assert len(query(f"what_is({canine}, res)")) == 1
assert qvar(f"what_is({wolf}, res)", "res") == ["wolf", "canine"]
assert qvar(f"what_is({dog}, res)", "res") == ["dog", "canine"]
assert qvar(f"what_is({canine}, res)", "res") == ["canine"]
def test_anything_works(polar, query):
polar.load_str("f(1);")
results = query("f(x)")
assert results[0]["x"] == 1
results = query("f(y)")
assert results[0]["y"] == 1
def test_method_with_kwargs(polar, qvar):
class Test:
def kwarg_method(self, x=1, y=2):
self.x = x
self.y = y
return True
polar.register_class(Test)
rules = """
defaults(result) if
test = new Test() and
test.kwarg_method() and
result = [test.x, test.y];
kwargs(result) if
test = new Test() and
test.kwarg_method(y: 4, x: 3) and
result = [test.x, test.y];
args(result) if
test = new Test() and
test.kwarg_method(5, 6) and
result = [test.x, test.y];
mixed(result) if
test = new Test() and
test.kwarg_method(7, y: 8) and
result = [test.x, test.y];
"""
polar.load_str(rules)
qvar("defaults(result)", "result") == [1, 2]
qvar("kwargs(result)", "result") == [3, 4]
qvar("args(result)", "result") == [5, 6]
qvar("mixed(result)", "result") == [7, 8]
def test_class_specializers(polar, qvar, qeval, query):
class A:
def a(self):
return "A"
def x(self):
return "A"
class B(A):
def b(self):
return "B"
def x(self):
return "B"
class C(B):
def c(self):
return "C"
def x(self):
return "C"
class X:
def x(self):
return "X"
polar.register_class(A)
polar.register_class(B)
polar.register_class(C)
polar.register_class(X)
rules = """
test(_: A);
test(_: B);
try(_: B, res) if res = 2;
try(_: C, res) if res = 3;
try(_: A, res) if res = 1;
"""
polar.load_str(rules)
assert qvar("new A().a() = x", "x", one=True) == "A"
assert qvar("new A().x() = x", "x", one=True) == "A"
assert qvar("new B().a() = x", "x", one=True) == "A"
assert qvar("new B().b() = x", "x", one=True) == "B"
assert qvar("new B().x() = x", "x", one=True) == "B"
assert qvar("new C().a() = x", "x", one=True) == "A"
assert qvar("new C().b() = x", "x", one=True) == "B"
assert qvar("new C().c() = x", "x", one=True) == "C"
assert qvar("new C().x() = x", "x", one=True) == "C"
assert qvar("new X().x() = x", "x", one=True) == "X"
assert len(query("test(new A())")) == 1
assert len(query("test(new B())")) == 2
assert qvar("try(new A(), x)", "x") == [1]
assert qvar("try(new B(), x)", "x") == [2, 1]
assert qvar("try(new C(), x)", "x") == [3, 2, 1]
assert qvar("try(new X(), x)", "x") == []
def test_class_specializers(polar, qvar, qeval, query):
class A:
def a(self):
return "A"
def x(self):
return "A"
class B(A):
def b(self):
return "B"
def x(self):
return "B"
class C(B):
def c(self):
return "C"
def x(self):
return "C"
class X:
def x(self):
return "X"
polar.register_class(A)
polar.register_class(B)
polar.register_class(C)
polar.register_class(X)
rules = """
test(_: A{});
test(_: B{});
try(_: B{}, res) if res = 2;
try(_: C{}, res) if res = 3;
try(_: A{}, res) if res = 1;
"""
polar.load_str(rules)
assert qvar("new A{}.a = x", "x", one=True) == "A"
assert qvar("new A{}.x = x", "x", one=True) == "A"
assert qvar("new B{}.a = x", "x", one=True) == "A"
assert qvar("new B{}.b = x", "x", one=True) == "B"
assert qvar("new B{}.x = x", "x", one=True) == "B"
assert qvar("new C{}.a = x", "x", one=True) == "A"
assert qvar("new C{}.b = x", "x", one=True) == "B"
assert qvar("new C{}.c = x", "x", one=True) == "C"
assert qvar("new C{}.x = x", "x", one=True) == "C"
assert qvar("new X{}.x = x", "x", one=True) == "X"
assert len(query("test(new A{})")) == 1
assert len(query("test(new B{})")) == 2
assert qvar("try(new A{}, x)", "x") == [1]
assert qvar("try(new B{}, x)", "x") == [2, 1]
assert qvar("try(new C{}, x)", "x") == [3, 2, 1]
assert qvar("try(new X{}, x)", "x") == []
def test_data_conversions(polar, qvar, query):
polar.load_str('a(1);b("two");c(true);d([1,"two",true]);')
assert qvar("a(x)", "x", one=True) == 1
assert qvar("b(x)", "x", one=True) == "two"
assert qvar("c(x)", "x", one=True)
assert qvar("d(x)", "x", one=True) == [1, "two", True]
y = qvar("x = y", "x", one=True)
assert str(y) == "Variable('y')"
assert repr(y) == "Variable('y')"
def test_parser_errors(polar):
# IntegerOverflow
rules = """
f(a) if a = 18446744073709551616;
"""
with pytest.raises(exceptions.IntegerOverflow) as e:
polar.load_str(rules)
assert (
str(e.value) ==
"'18446744073709551616' caused an integer overflow at line 2, column 17"
)
# InvalidTokenCharacter
rules = """
f(a) if a = "this is not
allowed";
"""
with pytest.raises(exceptions.InvalidTokenCharacter) as e:
polar.load_str(rules)
assert (
str(e.value) ==
"'\\n' is not a valid character. Found in this is not at line 2, column 29"
)
rules = """
f(a) if a = "this is not allowed\0
"""
with pytest.raises(exceptions.InvalidTokenCharacter) as e:
polar.load_str(rules)
assert (
str(e.value) ==
"'\\u{0}' is not a valid character. Found in this is not allowed at line 2, column 17"
)
# InvalidToken -- not sure what causes this
# UnrecognizedEOF
rules = """
f(a)
"""
with pytest.raises(exceptions.UnrecognizedEOF) as e:
polar.load_str(rules)
assert (
str(e.value) ==
"hit the end of the file unexpectedly. Did you forget a semi-colon at line 2, column 9"
)
# UnrecognizedToken
rules = """
1;
"""
with pytest.raises(exceptions.UnrecognizedToken) as e:
polar.load_str(rules)
assert str(
e.value) == "did not expect to find the token '1' at line 2, column 5"
def test_clear_rules(polar, query):
class Test:
pass
polar.register_class(Test)
polar.load_str("f(x) if x = 1;")
assert len(query("f(1)")) == 1
assert len(query("x = new Test()")) == 1
polar.clear_rules()
assert len(query("f(1)")) == 0
assert len(query("x = new Test()")) == 1
def test_unbound_variable(polar, query):
"""Test that unbound variable is returned."""
polar.load_str("rule(x, y) if y = 1;")
first = query("rule(x, y)")[0]
# y will be bound to 1
first["y"] = 1
# x should be unbound
assert isinstance(first["x"], Variable)
def test_return_list(polar, query):
class User:
def groups(self):
return ["engineering", "social", "admin"]
polar.register_class(User)
# for testing lists
polar.load_str('allow(actor: User, "join", "party") if "social" in actor.groups();')
assert query(Predicate(name="allow", args=[User(), "join", "party"]))
def test_static_method(polar, qeval):
class Foo(list):
@staticmethod
def plus_one(x):
return x + 1
def map(self, f):
return [f(x) for x in self]
polar.register_class(Foo)
polar.load_str("f(x: Foo) if x.map(Foo.plus_one) = [2, 3, 4];")
assert next(polar.query_rule("f", Foo([1, 2, 3])))
def test_datetime(polar, query):
# test datetime comparison
t1 = datetime(2020, 5, 25)
t2 = datetime.now()
t3 = datetime(2030, 5, 25)
t4 = datetime(2020, 5, 26)
polar.load_str("lt(a, b) if a < b;")
assert query(Predicate("lt", [t1, t2]))
assert not query(Predicate("lt", [t2, t1]))
# test creating datetime from polar
polar.load_str("dt(x) if x = new Datetime(year: 2020, month: 5, day: 25);")
assert query(Predicate("dt", [Variable("x")])) == [{
"x":
datetime(2020, 5, 25)
}]
polar.load_str("ltnow(x) if x < Datetime.now();")
assert query(Predicate("ltnow", [t1]))
assert not query(Predicate("ltnow", [t3]))
polar.load_str(
"timedelta(a: Datetime, b: Datetime) if a.__sub__(b) == new Timedelta(days: 1);"
)
assert query(Predicate("timedelta", [t4, t1]))
def test_unify(polar, qeval):
class Foo:
def __init__(self, foo):
self.foo = foo
def __eq__(self, other):
if isinstance(other, Foo):
return self.foo == other.foo
return False
polar.register_class(Foo)
polar.load_str("foo() if new Foo(foo: 1) = new Foo(foo: 1);")
assert qeval("foo()")
def test_runtime_errors(polar, query):
rules = """
foo(a,b) if a in b;
"""
polar.load_str(rules)
with pytest.raises(exceptions.PolarRuntimeException) as e:
query("foo(1,2)")
assert (str(e.value) == """trace (most recent evaluation last):
in query at line 1, column 1
foo(1,2)
in rule foo at line 2, column 17
a in b
Type error: can only use `in` on a list, this is Variable(Symbol("_a_3")) at line 2, column 17"""
)
def test_class_field_specializers(polar, qvar, qeval, query):
class Animal:
def __init__(self, species=None, genus=None, family=None):
self.genus = genus
self.species = species
self.family = family
polar.register_class(Animal)
rules = """
what_is(_: Animal, res) if res = "animal";
what_is(_: Animal{genus: "canis"}, res) if res = "canine";
what_is(_: Animal{family: "canidae"}, res) if res = "canid";
what_is(_: Animal{species: "canis lupus", genus: "canis"}, res) if res = "wolf";
what_is(_: Animal{species: "canis familiaris", genus: "canis"}, res) if res = "dog";
what_is(_: Animal{species: s, genus: "canis"}, res) if res = s;
"""
polar.load_str(rules)
wolf = 'new Animal(species: "canis lupus", genus: "canis", family: "canidae")'
dog = 'new Animal(species: "canis familiaris", genus: "canis", family: "canidae")'
canine = 'new Animal(genus: "canis", family: "canidae")'
canid = 'new Animal(family: "canidae")'
animal = "new Animal()"
assert len(query(f"what_is({wolf}, res)")) == 5
assert len(query(f"what_is({dog}, res)")) == 5
assert len(query(f"what_is({canine}, res)")) == 4
assert len(query(f"what_is({canid}, res)")) == 2
assert len(query(f"what_is({animal}, res)")) == 1
assert qvar(f"what_is({wolf}, res)", "res") == [
"wolf",
"canis lupus",
"canine",
"canid",
"animal",
]
assert qvar(f"what_is({dog}, res)", "res") == [
"dog",
"canis familiaris",
"canine",
"canid",
"animal",
]
assert qvar(f"what_is({canine}, res)",
"res") == [None, "canine", "canid", "animal"]
assert qvar(f"what_is({canid}, res)", "res") == ["canid", "animal"]
assert qvar(f"what_is({animal}, res)", "res") == ["animal"]
def test_return_none(polar, qeval):
class Foo:
def this_is_none(self):
return None
polar.register_class(Foo)
polar.load_str("f(x) if x.this_is_none = 1;")
assert not list(polar.query_rule("f", Foo()))
polar.load_str("f(x) if x.this_is_none.bad_call = 1;")
with pytest.raises(exceptions.PolarRuntimeException) as e:
list(polar.query_rule("f", Foo()))
assert str(e.value).find(
"Application error: 'NoneType' object has no attribute 'bad_call'")
def test_instance_cache(polar, qeval, query):
class Counter:
count = 0
def __init__(self):
self.__class__.count += 1
polar.register_class(Counter)
polar.load_str("f(c: Counter) if c.count > 0;")
assert Counter.count == 0
c = Counter()
assert Counter.count == 1
assert query(Predicate(name="f", args=[c]))
assert Counter.count == 1
assert c not in polar.host.instances.values()
def test_runtime_errors(polar, query):
rules = """
foo(a,b) if a in b;
"""
polar.load_str(rules)
with pytest.raises(exceptions.PolarRuntimeError) as e:
query("foo(1,2)")
assert (
str(e.value)
== """trace (most recent evaluation last):
in query at line 1, column 1
foo(1,2)
in rule foo at line 2, column 17
a in b
Type error: can only use `in` on an iterable value, this is Number(Integer(2)) at line 1, column 7"""
)
def test_partial(polar):
polar.load_str("f(1);")
polar.load_str("f(x) if x = 1 and x = 2;")
results = polar.query_rule("f", Partial("x"))
first = next(results)
x = first["bindings"]["x"]
assert unwrap_and(x) == Expression("Unify", [Variable("_this"), 1])
second = next(results)
x = second["bindings"]["x"]
# Top level should be and
and_args = unwrap_and(x)
assert and_args[0] == Expression("Unify", [Variable("_this"), 1])
polar.load_str("g(x) if x.bar = 1 and x.baz = 2;")
results = polar.query_rule("g", Partial("x"))
first = next(results)
x = first["bindings"]["x"]
and_args = unwrap_and(x)
assert len(and_args) == 2
assert unwrap_and(and_args[0]) == Expression(
"Unify", [Expression("Dot", [Variable("_this"), "bar"]), 1]
)
assert unwrap_and(and_args[1]) == Expression(
"Unify", [Expression("Dot", [Variable("_this"), "baz"]), 2]
)
def test_external_op(polar, query):
class A:
def __init__(self, a):
self.a = a
def __gt__(self, other):
return self.a > other.a
def __lt__(self, other):
return self.a < other.a
def __eq__(self, other):
return self.a == other.a
polar.register_class(A)
a1 = A(1)
a2 = A(2)
polar.load_str("lt(a, b) if a < b;")
polar.load_str("gt(a, b) if a > b;")
assert query(Predicate("lt", [a1, a2]))
assert not query(Predicate("lt", [a2, a1]))
assert query(Predicate("gt", [a2, a1]))
def test_specializers_mixed(polar, qvar, qeval, query):
class Animal:
def __init__(self, species=None, genus=None, family=None):
self.genus = genus
self.species = species
self.family = family
polar.register_class(Animal)
# load rules
rules = """
what_is(_: Animal, res) if res = "animal_class";
what_is(_: Animal{genus: "canis"}, res) if res = "canine_class";
what_is(_: {genus: "canis"}, res) if res = "canine_dict";
what_is(_: Animal{family: "canidae"}, res) if res = "canid_class";
what_is(_: {species: "canis lupus", genus: "canis"}, res) if res = "wolf_dict";
what_is(_: {species: "canis familiaris", genus: "canis"}, res) if res = "dog_dict";
what_is(_: Animal{species: "canis lupus", genus: "canis"}, res) if res = "wolf_class";
what_is(_: Animal{species: "canis familiaris", genus: "canis"}, res) if res = "dog_class";
"""
polar.load_str(rules)
wolf = 'new Animal(species: "canis lupus", genus: "canis", family: "canidae")'
dog = 'new Animal(species: "canis familiaris", genus: "canis", family: "canidae")'
canine = 'new Animal(genus: "canis", family: "canidae")'
wolf_dict = '{species: "canis lupus", genus: "canis", family: "canidae"}'
dog_dict = '{species: "canis familiaris", genus: "canis", family: "canidae"}'
canine_dict = '{genus: "canis", family: "canidae"}'
# test number of results
assert len(query(f"what_is({wolf}, res)")) == 6
assert len(query(f"what_is({dog}, res)")) == 6
assert len(query(f"what_is({canine}, res)")) == 4
assert len(query(f"what_is({wolf_dict}, res)")) == 2
assert len(query(f"what_is({dog_dict}, res)")) == 2
assert len(query(f"what_is({canine_dict}, res)")) == 1
# test rule ordering for instances
assert qvar(f"what_is({wolf}, res)", "res") == [
"wolf_class",
"canine_class",
"canid_class",
"animal_class",
"wolf_dict",
"canine_dict",
]
assert qvar(f"what_is({dog}, res)", "res") == [
"dog_class",
"canine_class",
"canid_class",
"animal_class",
"dog_dict",
"canine_dict",
]
assert qvar(f"what_is({canine}, res)", "res") == [
"canine_class",
"canid_class",
"animal_class",
"canine_dict",
]
# test rule ordering for dicts
assert qvar(f"what_is({wolf_dict}, res)",
"res") == ["wolf_dict", "canine_dict"]
assert qvar(f"what_is({dog_dict}, res)",
"res") == ["dog_dict", "canine_dict"]
assert qvar(f"what_is({canine_dict}, res)", "res") == ["canine_dict"]
def test_nil(polar, query, qvar):
"""Test that nil is pre-registered as None."""
polar.load_str("null(nil);")
assert qvar("null(x)", "x") == [None]
assert query(Predicate("null", [None])) == [{}]
assert not query(Predicate("null", [[]]))
def test_in(polar, qeval):
polar.load_str("g(x, y) if not x in y;")
polar.load_str("f(x) if not (x=1 or x=2);")
assert not qeval("f(1)")
assert qeval("g(4, [1,2,3])")
assert not qeval("g(1, [1,1,1])")
def test_predicate(polar, qvar, query):
"""Test that predicates can be converted to and from python."""
polar.load_str("f(x) if x = pred(1, 2);")
assert qvar("f(x)", "x") == [Predicate("pred", [1, 2])]
assert query(Predicate(name="f", args=[Predicate("pred", [1, 2])])) == [{}]