def test_state():
state = State()
P = Variable.parse("P")
kitchen = Variable.parse("kitchen: r")
study = Variable.parse("study: r")
stove = Variable.parse("stove: o")
at_kitchen = Proposition.parse("at(P, kitchen: r)")
in_kitchen = Proposition.parse("in(stove: o, kitchen: r)")
at_study = Proposition.parse("at(P, study: r)")
assert not state.is_fact(at_kitchen)
assert not state.is_fact(in_kitchen)
assert not state.is_fact(at_study)
assert len(state.variables) == 0
assert len(state.variables_of_type("P")) == 0
assert len(state.variables_of_type("r")) == 0
assert len(state.variables_of_type("o")) == 0
state.add_fact(at_kitchen)
state.add_fact(in_kitchen)
assert state.is_fact(at_kitchen)
assert state.is_fact(in_kitchen)
assert not state.is_fact(at_study)
assert set(state.variables) == {P, kitchen, stove}
assert state.variables_of_type("P") == {P}
assert state.variables_of_type("r") == {kitchen}
assert state.variables_of_type("o") == {stove}
state.remove_fact(at_kitchen)
assert not state.is_fact(at_kitchen)
assert state.is_fact(in_kitchen)
assert not state.is_fact(at_study)
assert set(state.variables) == {kitchen, stove}
assert len(state.variables_of_type("P")) == 0
assert state.variables_of_type("r") == {kitchen}
assert state.variables_of_type("o") == {stove}
state.remove_fact(in_kitchen)
assert not state.is_fact(at_kitchen)
assert not state.is_fact(in_kitchen)
assert not state.is_fact(at_study)
assert len(state.variables) == 0
assert len(state.variables_of_type("P")) == 0
assert len(state.variables_of_type("r")) == 0
assert len(state.variables_of_type("o")) == 0
state.add_fact(at_study)
assert not state.is_fact(at_kitchen)
assert not state.is_fact(in_kitchen)
assert state.is_fact(at_study)
assert set(state.variables) == {P, study}
assert state.variables_of_type("P") == {P}
assert state.variables_of_type("r") == {study}
assert len(state.variables_of_type("o")) == 0
def try_instantiate(self, state: State, partial: _PartialAction) -> Optional[Action]:
"""
Try to instantiate a partial action, by creating new variables if
necessary.
"""
rule, mapping = partial.rule, partial.mapping
if self.create_variables:
type_counts = Counter({ph.type: len(state.variables_of_type(ph.type)) for ph in rule.placeholders})
for ph in rule.placeholders:
if mapping.get(ph) is None:
var = self.create_variable(state, ph, type_counts)
if var:
mapping[ph] = var
else:
return None
return rule.instantiate(mapping)