How to spy call of async/await function?

[hyzhak]

I'm trying to do this:

async def async_func2():
    pass


async def async_func1():
    await async_func2()


@pytest.mark.asyncio
async def test_async_func2(mocker):
    mock_async_func2 = mocker.patch(__name__ + '.async_func2')
    mock_async_func2.return_value = 'something'
    res = await async_func1()
    mock_async_func2.assert_called_once_with()

But got:

_________________________________________ test_async_func2 __________________________________________

mocker = <pytest_mock.MockFixture object at 0x7febf7b4c1d0>

    @pytest.mark.asyncio
    async def test_async_func2(mocker):
        mock_async_func2 = mocker.patch(__name__ + '.async_func2')
        mock_async_func2.return_value = 'something'
>       res = await async_func1()

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

    async def async_func1():
>       await async_func2()
E       TypeError: object str can't be used in 'await' expression

My goal is to mock async_func2 function and catch all calls of it. How can I archive it with this library?

[hyzhak]

solution was much simpler than I thought:

@pytest.mark.asyncio
async def test_async_func2(mocker):
    mock_async_func2 = mocker.patch(__name__ + '.async_func2')
    async def return_async_value(val):
        return val
    mock_async_func2.return_value = return_async_value('something')
    res = await async_func1()
    mock_async_func2.assert_called_once_with()
    assert res == 'something'

thanks! :)

[leftvalue]

but I can only run the async_func1 once or I got an error

async def async_func2():
    pass


async def async_func1():
    await async_func2()


@pytest.mark.asyncio
async def test_async_func2(mocker):
    mock_async_func2 = mocker.patch(__name__ + '.async_func2')

    async def return_async_value(val):
        return val

    mock_async_func2.return_value = return_async_value('something')
    res = await mock_async_func2()
    res = await mock_async_func2()
    mock_async_func2.assert_called_once_with()
    assert res == 'something'

run pytest and got

mocker = <pytest_mock.plugin.MockFixture object at 0x103cd2ac8>

    @pytest.mark.asyncio
    async def test_async_func2(mocker):
        mock_async_func2 = mocker.patch(__name__ + '.async_func2')
    
        async def return_async_value(val):
            return val
    
        mock_async_func2.return_value = return_async_value('something')
        res = await mock_async_func2()
>       res = await mock_async_func2()
E       RuntimeError: cannot reuse already awaited coroutine

desktop_top_trending_test.py:101: RuntimeError

[leftvalue]

finally I found a solution

async def async_func2():
    pass


async def async_func1():
    await async_func2()


@pytest.mark.asyncio
async def test_async_func2(mocker):
    mock_async_func2 = mocker.patch(__name__ + '.async_func2')

    def return_async_value(val):
        f = asyncio.Future()
        f.set_result(val)
        return f

    mock_async_func2.return_value = return_async_value('something')
    res = await mock_async_func2()
    print(res)
    res = await mock_async_func2()
    print(res)
    # mock_async_func2.assert_called_once_with()
    assert res == 'something'

this idea come from discussion