import unittest
try:
    from .lib_fibonacci import fibonacci_generator
    from .lib_fibonacci import fibonacci_generator_smaller
    from .lib_fibonacci import fibonacci_nth
except ModuleNotFoundError:
    from lib_fibonacci import fibonacci_generator
    from lib_fibonacci import fibonacci_generator_smaller
    from lib_fibonacci import fibonacci_nth


class TestFibonacciMethods(unittest.TestCase):

    def test_fibonacci_generator(self):
        g = fibonacci_generator()
        fs = [next(g) for _ in range(10)]
        self.assertEqual(fs, [1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
        self.assertNotEqual(fs, [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55])

    def test_fibonacci_generator_smaller(self):
        g = fibonacci_generator_smaller(20)
        self.assertEqual(list(g), [1, 1, 2, 3, 5, 8, 13])

    def test_fibonacci_nth(self):
        self.assertEqual(fibonacci_nth(0), 0)
        self.assertEqual(fibonacci_nth(1), 1)
        self.assertEqual(fibonacci_nth(2), 1)
        self.assertEqual(fibonacci_nth(3), 2)
        self.assertEqual(fibonacci_nth(4), 3)
        self.assertEqual(fibonacci_nth(5), 5)
        self.assertEqual(fibonacci_nth(6), 8)


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