Typechecking for Python - Test Suite

typecheck_test.py

"""
Quick unit-test for typecheck.py.
Wonder if there's any way to unittest an exception's text?
"""

import unittest
from typecheck import typecheck

@typecheck
def add(x: int, y: int) -> int:
    """Returns the sum of the integers x and y as an integer."""
    return x + y

@typecheck
def addReturnsString(x: int, y: int) -> int:
    """Returns the sum of the integers x and y as an 'integer'."""
    return str(x + y)

class TestTypeChecking(unittest.TestCase):
    def test_correct(self):
        self.assertIsInstance(add(4,5), int)

    def test_return_type(self):
        with self.assertRaises(TypeError):
            addReturnsString(54, 4)

    def test_arg_type(self):
        with self.assertRaises(TypeError):
            add(4, "hello")

if __name__ == "__main__":
    unittest.main()