import unittest

from count_calls import count_calls


class CountCallsTests(unittest.TestCase):

    """Tests for count_calls."""

    def test_call_count_starts_at_zero(self):
        counter = count_calls()
        self.assertEqual(counter.calls, 0)

    def test_call_count_increments(self):
        counter = count_calls()
        self.assertEqual(counter.calls, 0)
        counter()
        self.assertEqual(counter.calls, 1)
        counter()
        self.assertEqual(counter.calls, 2)

    # To test the Bonus part of this exercise, comment out the following line
    @unittest.expectedFailure
    def test_accepts_and_calls_a_function(self):
        # Function value is returned
        def one(): return 1
        decorated = count_calls(one)
        self.assertEqual(decorated(), 1)
        self.assertEqual(decorated.calls, 1)

        # Function is called each time
        recordings = []
        def my_func():
            recordings.append('call')
            return recordings
        decorated = count_calls(my_func)
        self.assertEqual(recordings, [])
        self.assertEqual(decorated.calls, 0)
        self.assertEqual(decorated(), ['call'])
        self.assertEqual(decorated.calls, 1)
        self.assertEqual(decorated(), ['call', 'call'])
        self.assertEqual(decorated.calls, 2)

    # To test the Bonus part of this exercise, comment out the following line
    @unittest.expectedFailure
    def test_accepts_arguments(self):
        # Function accepts positional arguments
        @count_calls
        def add(x, y):
            return x + y
        self.assertEqual(add(1, 2), 3)
        self.assertEqual(add(1, 3), 4)

        # Function accepts keyword arguments
        recordings = []
        @count_calls
        def my_func(*args, **kwargs):
            recordings.append((args, kwargs))
            return recordings
        self.assertEqual(my_func(), [((), {})])
        self.assertEqual(my_func(1, 2, a=3), [((), {}), ((1, 2), {'a': 3})])

        # Exceptions are still counted as calls
        @count_calls
        def my_func():
            raise AssertionError("Function called too soon")
        self.assertEqual(my_func.calls, 0)
        with self.assertRaises(AssertionError):
            my_func()
        self.assertEqual(my_func.calls, 1)
        self.assertEqual(my_func.calls, 1)
        with self.assertRaises(AssertionError):
            my_func()
        self.assertEqual(my_func.calls, 2)

    # To test the Bonus part of this exercise, comment out the following line
    @unittest.expectedFailure
    def test_docstring_and_name_preserved(self):
        import pydoc
        decorated = count_calls(example)
        self.assertIn('function example', str(decorated))
        documentation = pydoc.render_doc(decorated)
        self.assertIn('function example', documentation)
        self.assertIn('Example function.', documentation)
        self.assertIn('(a, b=True)', documentation)


def example(a, b=True):
    """Example function."""
    print('hello world')


if __name__ == "__main__":
    unittest.main(verbosity=2)