"""Assertions for runtime type checking of function arguments."""
from typing import Any
def assert_is_string(value: Any, name: str) -> None:
"""If :param value: isn't of type str, raise a TypeError.
>>> try: assert_is_string(123, 'var')
... except TypeError as type_error: print(str(type_error))
...
expected variable 'var', with value 123, to have type 'str', not 'int'
"""
if not isinstance(value, str):
raise TypeError(
f"expected variable '{name}', with value {str(value)}, to have"
+ f" type 'str', not '{type(value).__name__}'"
)
def assert_is_list(value: Any, name: str) -> None:
"""If :param value: isn't of type list, raise a TypeError.
>>> try: assert_is_list(123, 'var')
... except TypeError as type_error: print(str(type_error))
...
expected variable 'var', with value 123, to have type 'list', not 'int'
"""
if not isinstance(value, list):
raise TypeError(
f"expected variable '{name}', with value {str(value)}, to have"
+ f" type 'list', not '{type(value).__name__}'"
)
def assert_is_int(value: Any, name: str) -> None:
"""If :param value: isn't of type int, raise a TypeError.
>>> try: assert_is_int('asdf', 'var')
... except TypeError as type_error: print(str(type_error))
...
expected variable 'var', with value asdf, to have type 'int', not 'str'
"""
if not isinstance(value, int):
raise TypeError(
f"expected variable '{name}', with value {str(value)}, to have"
+ f" type 'int', not '{type(value).__name__}'"
)