def __missing__(self, types: tuple) -> Callable:
"""Find and cache the next applicable method of given types."""
self.evaluate()
if types in self:
return self[types]
groups = groupby(signature(types).__sub__, self.parents(types))
keys = groups[min(groups)] if groups else []
funcs = {self[key] for key in keys}
if len(funcs) == 1:
return self.setdefault(types, *funcs)
msg = f"{self.__name__}: {len(keys)} methods found" # type: ignore
raise DispatchError(msg, types, keys)
def __setitem__(self, types: tuple, func: Callable):
self.clean()
types = signature(types)
parents = types.parents = self.parents(types)
for key in self:
if types < key and (not parents or parents & key.parents):
key.parents -= parents
key.parents.add(types)
if any(map(subtype.subcheck, types)):
self.get_type = get_type # switch to slower generic type checker
super().__setitem__(types, func)
self.__doc__ = self.docstring
def test_signature():
with pytest.raises(TypeError):
signature([list]) <= signature([None])
def test_signature():
assert signature([List]) <= signature([list])
assert signature([list]) <= signature([List])
assert signature([List[int]]) <= signature([list])
assert signature([list]) <= signature([List[int]])
assert signature([List[int]]) - signature([list]) == [0]
assert signature([list]) - signature([List[int]]) == [1]
def test_signature():
assert signature([Any, List]) == (object, list)
assert signature([List]) <= signature([list])
assert signature([list]) <= signature([List])
assert signature([list]) <= signature([List[int]])
assert signature([List[int]]) - signature([list])
assert signature([list]) - signature([List[int]]) == (1,)
def test_signature():
assert signature([Any, List]) == (object, list)
assert signature([AnyStr]) == signature([Union[bytes, str]])
assert signature([List]) <= signature([list])
assert signature([list]) <= signature([List])
assert signature([list]) <= signature([List[int]])
assert signature([List[int]]) - signature([list])
assert signature([list]) - signature([List[int]]) == (1,)
def test_signature():
assert signature([Any, List]) == (object, list)
assert signature([AnyStr]) == signature([Union[bytes, str]])
assert signature([TypeVar('T')]) == signature([object])
assert signature([int]) - signature([Union[int, float]]) == (0, )
assert signature([List]) <= signature([list])
assert signature([list]) <= signature([List])
assert signature([list]) <= signature([List[int]])
assert signature([List[int]]) - signature([list])
assert signature([list]) - signature([List[int]]) == (1, )
# with metaclasses:
assert signature([type]) - signature([type]) == (0, )
assert signature([type]) - signature([object]) == (1, )
# using EnumMeta because it is a standard, stable, metaclass
assert signature([enum.EnumMeta]) - signature([object]) == (2, )
assert signature([Union[type, enum.EnumMeta]]) - signature([object]) == (
1, )