def is_closed_python_list_type(ttype):
origin = get_origin(ttype)
args = get_args(ttype)
return (origin is list and args != ()
# py3.7 compat
and type(args[0]) != typing.TypeVar)
def is_closed_python_tuple_type(ttype):
"""
A "closed" generic type has all of its type parameters parameterized
by other closed or concrete types.
e.g.
Returns true for Tuple[int] or Tuple[str, int] but false for Tuple or tuple
"""
origin = get_origin(ttype)
args = get_args(ttype)
return origin is tuple and args != ()
def is_closed_python_set_type(ttype):
"""
A "closed" generic type has all of its type parameters parameterized
by other closed or concrete types.
e.g.
Returns true for Set[string] but false for Set or set
"""
origin = get_origin(ttype)
args = get_args(ttype)
return (origin is set and args != ()
# py3.7 compat
and type(args[0]) != typing.TypeVar)
def is_closed_python_dict_type(ttype):
"""A "closed" generic type has all of its type parameters parameterized
by other closed or concrete types.
e.g.
Returns true for typing.Dict[int, str] but not for typing.Dict.
Tests document current behavior (not recursive) -- i.e., typing.Dict[str, Dict] returns True.
"""
origin = get_origin(ttype)
args = get_args(ttype)
return (origin is dict and args != ()
# py3.7 compat
and type(args[0]) != typing.TypeVar and
type(args[1]) != typing.TypeVar)
def get_tuple_type_params(ttype):
check.param_invariant(is_closed_python_tuple_type(ttype), "ttype")
return get_args(ttype)
def get_set_inner_type(ttype):
check.param_invariant(is_closed_python_set_type(ttype), "ttype")
return get_args(ttype)[0]
def is_closed_python_optional_type(ttype):
# Optional[X] is Union[X, NoneType] which is what we match against here
origin = get_origin(ttype)
args = get_args(ttype)
return origin is typing.Union and len(args) == 2 and args[1] is type(None)
def get_optional_inner_type(ttype):
check.invariant(is_closed_python_optional_type(ttype),
"type must pass is_closed_python_optional_type check")
return get_args(ttype)[0]
def get_dict_key_value_types(ttype):
check.param_invariant(is_closed_python_dict_type(ttype), "ttype")
return get_args(ttype)