cpython/Lib/unittest/test/testmock/testasync.py

import asyncio
import inspect
import unittest

from unittest.mock import (call, AsyncMock, patch, MagicMock, create_autospec,
                           _AwaitEvent)


def tearDownModule():
    asyncio.set_event_loop_policy(None)


class AsyncClass:
    def __init__(self):
        pass
    async def async_method(self):
        pass
    def normal_method(self):
        pass

async def async_func():
    pass

async def async_func_args(a, b, *, c):
    pass

def normal_func():
    pass

class NormalClass(object):
    def a(self):
        pass


async_foo_name = f'{__name__}.AsyncClass'
normal_foo_name = f'{__name__}.NormalClass'


class AsyncPatchDecoratorTest(unittest.TestCase):
    def test_is_coroutine_function_patch(self):
        @patch.object(AsyncClass, 'async_method')
        def test_async(mock_method):
            self.assertTrue(asyncio.iscoroutinefunction(mock_method))
        test_async()

    def test_is_async_patch(self):
        @patch.object(AsyncClass, 'async_method')
        def test_async(mock_method):
            m = mock_method()
            self.assertTrue(inspect.isawaitable(m))
            asyncio.run(m)

        @patch(f'{async_foo_name}.async_method')
        def test_no_parent_attribute(mock_method):
            m = mock_method()
            self.assertTrue(inspect.isawaitable(m))
            asyncio.run(m)

        test_async()
        test_no_parent_attribute()

    def test_is_AsyncMock_patch(self):
        @patch.object(AsyncClass, 'async_method')
        def test_async(mock_method):
            self.assertIsInstance(mock_method, AsyncMock)

        test_async()

    def test_async_def_patch(self):
        @patch(f"{__name__}.async_func", AsyncMock())
        async def test_async():
            self.assertIsInstance(async_func, AsyncMock)

        asyncio.run(test_async())
        self.assertTrue(inspect.iscoroutinefunction(async_func))


class AsyncPatchCMTest(unittest.TestCase):
    def test_is_async_function_cm(self):
        def test_async():
            with patch.object(AsyncClass, 'async_method') as mock_method:
                self.assertTrue(asyncio.iscoroutinefunction(mock_method))

        test_async()

    def test_is_async_cm(self):
        def test_async():
            with patch.object(AsyncClass, 'async_method') as mock_method:
                m = mock_method()
                self.assertTrue(inspect.isawaitable(m))
                asyncio.run(m)

        test_async()

    def test_is_AsyncMock_cm(self):
        def test_async():
            with patch.object(AsyncClass, 'async_method') as mock_method:
                self.assertIsInstance(mock_method, AsyncMock)

        test_async()

    def test_async_def_cm(self):
        async def test_async():
            with patch(f"{__name__}.async_func", AsyncMock()):
                self.assertIsInstance(async_func, AsyncMock)
            self.assertTrue(inspect.iscoroutinefunction(async_func))

        asyncio.run(test_async())


class AsyncMockTest(unittest.TestCase):
    def test_iscoroutinefunction_default(self):
        mock = AsyncMock()
        self.assertTrue(asyncio.iscoroutinefunction(mock))

    def test_iscoroutinefunction_function(self):
        async def foo(): pass
        mock = AsyncMock(foo)
        self.assertTrue(asyncio.iscoroutinefunction(mock))
        self.assertTrue(inspect.iscoroutinefunction(mock))

    def test_isawaitable(self):
        mock = AsyncMock()
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)
        self.assertIn('assert_awaited', dir(mock))

    def test_iscoroutinefunction_normal_function(self):
        def foo(): pass
        mock = AsyncMock(foo)
        self.assertTrue(asyncio.iscoroutinefunction(mock))
        self.assertTrue(inspect.iscoroutinefunction(mock))

    def test_future_isfuture(self):
        loop = asyncio.new_event_loop()
        asyncio.set_event_loop(loop)
        fut = asyncio.Future()
        loop.stop()
        loop.close()
        mock = AsyncMock(fut)
        self.assertIsInstance(mock, asyncio.Future)


class AsyncAutospecTest(unittest.TestCase):
    def test_is_AsyncMock_patch(self):
        @patch(async_foo_name, autospec=True)
        def test_async(mock_method):
            self.assertIsInstance(mock_method.async_method, AsyncMock)
            self.assertIsInstance(mock_method, MagicMock)

        @patch(async_foo_name, autospec=True)
        def test_normal_method(mock_method):
            self.assertIsInstance(mock_method.normal_method, MagicMock)

        test_async()
        test_normal_method()

    def test_create_autospec_instance(self):
        with self.assertRaises(RuntimeError):
            create_autospec(async_func, instance=True)

    def test_create_autospec(self):
        spec = create_autospec(async_func_args)
        awaitable = spec(1, 2, c=3)
        async def main():
            await awaitable

        self.assertEqual(spec.await_count, 0)
        self.assertIsNone(spec.await_args)
        self.assertEqual(spec.await_args_list, [])
        self.assertIsInstance(spec.awaited, _AwaitEvent)
        spec.assert_not_awaited()

        asyncio.run(main())

        self.assertTrue(asyncio.iscoroutinefunction(spec))
        self.assertTrue(asyncio.iscoroutine(awaitable))
        self.assertEqual(spec.await_count, 1)
        self.assertEqual(spec.await_args, call(1, 2, c=3))
        self.assertEqual(spec.await_args_list, [call(1, 2, c=3)])
        spec.assert_awaited_once()
        spec.assert_awaited_once_with(1, 2, c=3)
        spec.assert_awaited_with(1, 2, c=3)
        spec.assert_awaited()

    def test_patch_with_autospec(self):

        async def test_async():
            with patch(f"{__name__}.async_func_args", autospec=True) as mock_method:
                awaitable = mock_method(1, 2, c=3)
                self.assertIsInstance(mock_method.mock, AsyncMock)

                self.assertTrue(asyncio.iscoroutinefunction(mock_method))
                self.assertTrue(asyncio.iscoroutine(awaitable))
                self.assertTrue(inspect.isawaitable(awaitable))

                # Verify the default values during mock setup
                self.assertEqual(mock_method.await_count, 0)
                self.assertEqual(mock_method.await_args_list, [])
                self.assertIsNone(mock_method.await_args)
                self.assertIsInstance(mock_method.awaited, _AwaitEvent)
                mock_method.assert_not_awaited()

                await awaitable

            self.assertEqual(mock_method.await_count, 1)
            self.assertEqual(mock_method.await_args, call(1, 2, c=3))
            self.assertEqual(mock_method.await_args_list, [call(1, 2, c=3)])
            mock_method.assert_awaited_once()
            mock_method.assert_awaited_once_with(1, 2, c=3)
            mock_method.assert_awaited_with(1, 2, c=3)
            mock_method.assert_awaited()

            mock_method.reset_mock()
            self.assertEqual(mock_method.await_count, 0)
            self.assertIsNone(mock_method.await_args)
            self.assertEqual(mock_method.await_args_list, [])

        asyncio.run(test_async())


class AsyncSpecTest(unittest.TestCase):
    def test_spec_as_async_positional_magicmock(self):
        mock = MagicMock(async_func)
        self.assertIsInstance(mock, MagicMock)
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)

    def test_spec_as_async_kw_magicmock(self):
        mock = MagicMock(spec=async_func)
        self.assertIsInstance(mock, MagicMock)
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)

    def test_spec_as_async_kw_AsyncMock(self):
        mock = AsyncMock(spec=async_func)
        self.assertIsInstance(mock, AsyncMock)
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)

    def test_spec_as_async_positional_AsyncMock(self):
        mock = AsyncMock(async_func)
        self.assertIsInstance(mock, AsyncMock)
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)

    def test_spec_as_normal_kw_AsyncMock(self):
        mock = AsyncMock(spec=normal_func)
        self.assertIsInstance(mock, AsyncMock)
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)

    def test_spec_as_normal_positional_AsyncMock(self):
        mock = AsyncMock(normal_func)
        self.assertIsInstance(mock, AsyncMock)
        m = mock()
        self.assertTrue(inspect.isawaitable(m))
        asyncio.run(m)

    def test_spec_async_mock(self):
        @patch.object(AsyncClass, 'async_method', spec=True)
        def test_async(mock_method):
            self.assertIsInstance(mock_method, AsyncMock)

        test_async()

    def test_spec_parent_not_async_attribute_is(self):
        @patch(async_foo_name, spec=True)
        def test_async(mock_method):
            self.assertIsInstance(mock_method, MagicMock)
            self.assertIsInstance(mock_method.async_method, AsyncMock)

        test_async()

    def test_target_async_spec_not(self):
        @patch.object(AsyncClass, 'async_method', spec=NormalClass.a)
        def test_async_attribute(mock_method):
            self.assertIsInstance(mock_method, MagicMock)
            self.assertFalse(inspect.iscoroutine(mock_method))
            self.assertFalse(inspect.isawaitable(mock_method))

        test_async_attribute()

    def test_target_not_async_spec_is(self):
        @patch.object(NormalClass, 'a', spec=async_func)
        def test_attribute_not_async_spec_is(mock_async_func):
            self.assertIsInstance(mock_async_func, AsyncMock)
        test_attribute_not_async_spec_is()

    def test_spec_async_attributes(self):
        @patch(normal_foo_name, spec=AsyncClass)
        def test_async_attributes_coroutines(MockNormalClass):
            self.assertIsInstance(MockNormalClass.async_method, AsyncMock)
            self.assertIsInstance(MockNormalClass, MagicMock)

        test_async_attributes_coroutines()


class AsyncSpecSetTest(unittest.TestCase):
    def test_is_AsyncMock_patch(self):
        @patch.object(AsyncClass, 'async_method', spec_set=True)
        def test_async(async_method):
            self.assertIsInstance(async_method, AsyncMock)

    def test_is_async_AsyncMock(self):
        mock = AsyncMock(spec_set=AsyncClass.async_method)
        self.assertTrue(asyncio.iscoroutinefunction(mock))
        self.assertIsInstance(mock, AsyncMock)

    def test_is_child_AsyncMock(self):
        mock = MagicMock(spec_set=AsyncClass)
        self.assertTrue(asyncio.iscoroutinefunction(mock.async_method))
        self.assertFalse(asyncio.iscoroutinefunction(mock.normal_method))
        self.assertIsInstance(mock.async_method, AsyncMock)
        self.assertIsInstance(mock.normal_method, MagicMock)
        self.assertIsInstance(mock, MagicMock)


class AsyncArguments(unittest.TestCase):
    def test_add_return_value(self):
        async def addition(self, var):
            return var + 1

        mock = AsyncMock(addition, return_value=10)
        output = asyncio.run(mock(5))

        self.assertEqual(output, 10)

    def test_add_side_effect_exception(self):
        async def addition(var):
            return var + 1
        mock = AsyncMock(addition, side_effect=Exception('err'))
        with self.assertRaises(Exception):
            asyncio.run(mock(5))

    def test_add_side_effect_function(self):
        async def addition(var):
            return var + 1
        mock = AsyncMock(side_effect=addition)
        result = asyncio.run(mock(5))
        self.assertEqual(result, 6)

    def test_add_side_effect_iterable(self):
        vals = [1, 2, 3]
        mock = AsyncMock(side_effect=vals)
        for item in vals:
            self.assertEqual(item, asyncio.run(mock()))

        with self.assertRaises(RuntimeError) as e:
            asyncio.run(mock())
            self.assertEqual(
                e.exception,
                RuntimeError('coroutine raised StopIteration')
            )


class AsyncContextManagerTest(unittest.TestCase):

    class WithAsyncContextManager:

        async def __aenter__(self, *args, **kwargs):
            return self

        async def __aexit__(self, *args, **kwargs):
            pass

    def test_magic_methods_are_async_mocks(self):
        mock = MagicMock(self.WithAsyncContextManager())
        self.assertIsInstance(mock.__aenter__, AsyncMock)
        self.assertIsInstance(mock.__aexit__, AsyncMock)

    def test_mock_supports_async_context_manager(self):
        called = False
        instance = self.WithAsyncContextManager()
        mock_instance = MagicMock(instance)

        async def use_context_manager():
            nonlocal called
            async with mock_instance as result:
                called = True
            return result

        result = asyncio.run(use_context_manager())
        self.assertTrue(called)
        self.assertTrue(mock_instance.__aenter__.called)
        self.assertTrue(mock_instance.__aexit__.called)
        self.assertIsNot(mock_instance, result)
        self.assertIsInstance(result, AsyncMock)

    def test_mock_customize_async_context_manager(self):
        instance = self.WithAsyncContextManager()
        mock_instance = MagicMock(instance)

        expected_result = object()
        mock_instance.__aenter__.return_value = expected_result

        async def use_context_manager():
            async with mock_instance as result:
                return result

        self.assertIs(asyncio.run(use_context_manager()), expected_result)

    def test_mock_customize_async_context_manager_with_coroutine(self):
        enter_called = False
        exit_called = False

        async def enter_coroutine(*args):
            nonlocal enter_called
            enter_called = True

        async def exit_coroutine(*args):
            nonlocal exit_called
            exit_called = True

        instance = self.WithAsyncContextManager()
        mock_instance = MagicMock(instance)

        mock_instance.__aenter__ = enter_coroutine
        mock_instance.__aexit__ = exit_coroutine

        async def use_context_manager():
            async with mock_instance:
                pass

        asyncio.run(use_context_manager())
        self.assertTrue(enter_called)
        self.assertTrue(exit_called)

    def test_context_manager_raise_exception_by_default(self):
        async def raise_in(context_manager):
            async with context_manager:
                raise TypeError()

        instance = self.WithAsyncContextManager()
        mock_instance = MagicMock(instance)
        with self.assertRaises(TypeError):
            asyncio.run(raise_in(mock_instance))


class AsyncIteratorTest(unittest.TestCase):
    class WithAsyncIterator(object):
        def __init__(self):
            self.items = ["foo", "NormalFoo", "baz"]

        def __aiter__(self):
            return self

        async def __anext__(self):
            try:
                return self.items.pop()
            except IndexError:
                pass

            raise StopAsyncIteration

    def test_mock_aiter_and_anext(self):
        instance = self.WithAsyncIterator()
        mock_instance = MagicMock(instance)

        self.assertEqual(asyncio.iscoroutine(instance.__aiter__),
                         asyncio.iscoroutine(mock_instance.__aiter__))
        self.assertEqual(asyncio.iscoroutine(instance.__anext__),
                         asyncio.iscoroutine(mock_instance.__anext__))

        iterator = instance.__aiter__()
        if asyncio.iscoroutine(iterator):
            iterator = asyncio.run(iterator)

        mock_iterator = mock_instance.__aiter__()
        if asyncio.iscoroutine(mock_iterator):
            mock_iterator = asyncio.run(mock_iterator)

        self.assertEqual(asyncio.iscoroutine(iterator.__aiter__),
                         asyncio.iscoroutine(mock_iterator.__aiter__))
        self.assertEqual(asyncio.iscoroutine(iterator.__anext__),
                         asyncio.iscoroutine(mock_iterator.__anext__))

    def test_mock_async_for(self):
        async def iterate(iterator):
            accumulator = []
            async for item in iterator:
                accumulator.append(item)

            return accumulator

        expected = ["FOO", "BAR", "BAZ"]
        with self.subTest("iterate through default value"):
            mock_instance = MagicMock(self.WithAsyncIterator())
            self.assertEqual([], asyncio.run(iterate(mock_instance)))

        with self.subTest("iterate through set return_value"):
            mock_instance = MagicMock(self.WithAsyncIterator())
            mock_instance.__aiter__.return_value = expected[:]
            self.assertEqual(expected, asyncio.run(iterate(mock_instance)))

        with self.subTest("iterate through set return_value iterator"):
            mock_instance = MagicMock(self.WithAsyncIterator())
            mock_instance.__aiter__.return_value = iter(expected[:])
            self.assertEqual(expected, asyncio.run(iterate(mock_instance)))


class AsyncMockAssert(unittest.TestCase):
    def setUp(self):
        self.mock = AsyncMock()

    async def _runnable_test(self, *args):
        if not args:
            await self.mock()
        else:
            await self.mock(*args)

    def test_assert_awaited(self):
        with self.assertRaises(AssertionError):
            self.mock.assert_awaited()

        asyncio.run(self._runnable_test())
        self.mock.assert_awaited()

    def test_assert_awaited_once(self):
        with self.assertRaises(AssertionError):
            self.mock.assert_awaited_once()

        asyncio.run(self._runnable_test())
        self.mock.assert_awaited_once()

        asyncio.run(self._runnable_test())
        with self.assertRaises(AssertionError):
            self.mock.assert_awaited_once()

    def test_assert_awaited_with(self):
        asyncio.run(self._runnable_test())
        msg = 'expected await not found'
        with self.assertRaisesRegex(AssertionError, msg):
            self.mock.assert_awaited_with('foo')

        asyncio.run(self._runnable_test('foo'))
        self.mock.assert_awaited_with('foo')

        asyncio.run(self._runnable_test('SomethingElse'))
        with self.assertRaises(AssertionError):
            self.mock.assert_awaited_with('foo')

    def test_assert_awaited_once_with(self):
        with self.assertRaises(AssertionError):
            self.mock.assert_awaited_once_with('foo')

        asyncio.run(self._runnable_test('foo'))
        self.mock.assert_awaited_once_with('foo')

        asyncio.run(self._runnable_test('foo'))
        with self.assertRaises(AssertionError):
            self.mock.assert_awaited_once_with('foo')

    def test_assert_any_wait(self):
        with self.assertRaises(AssertionError):
            self.mock.assert_any_await('NormalFoo')

        asyncio.run(self._runnable_test('foo'))
        with self.assertRaises(AssertionError):
            self.mock.assert_any_await('NormalFoo')

        asyncio.run(self._runnable_test('NormalFoo'))
        self.mock.assert_any_await('NormalFoo')

        asyncio.run(self._runnable_test('SomethingElse'))
        self.mock.assert_any_await('NormalFoo')

    def test_assert_has_awaits_no_order(self):
        calls = [call('NormalFoo'), call('baz')]

        with self.assertRaises(AssertionError) as cm:
            self.mock.assert_has_awaits(calls)
        self.assertEqual(len(cm.exception.args), 1)

        asyncio.run(self._runnable_test('foo'))
        with self.assertRaises(AssertionError):
            self.mock.assert_has_awaits(calls)

        asyncio.run(self._runnable_test('NormalFoo'))
        with self.assertRaises(AssertionError):
            self.mock.assert_has_awaits(calls)

        asyncio.run(self._runnable_test('baz'))
        self.mock.assert_has_awaits(calls)

        asyncio.run(self._runnable_test('SomethingElse'))
        self.mock.assert_has_awaits(calls)

    def test_assert_has_awaits_ordered(self):
        calls = [call('NormalFoo'), call('baz')]
        with self.assertRaises(AssertionError):
            self.mock.assert_has_awaits(calls, any_order=True)

        asyncio.run(self._runnable_test('baz'))
        with self.assertRaises(AssertionError):
            self.mock.assert_has_awaits(calls, any_order=True)

        asyncio.run(self._runnable_test('foo'))
        with self.assertRaises(AssertionError):
            self.mock.assert_has_awaits(calls, any_order=True)

        asyncio.run(self._runnable_test('NormalFoo'))
        self.mock.assert_has_awaits(calls, any_order=True)

        asyncio.run(self._runnable_test('qux'))
        self.mock.assert_has_awaits(calls, any_order=True)

    def test_assert_not_awaited(self):
        self.mock.assert_not_awaited()

        asyncio.run(self._runnable_test())
        with self.assertRaises(AssertionError):
            self.mock.assert_not_awaited()