I am fixing an old test, that extensively uses mocks, and I encountered challenges setting them up. I have a peace of code that looks like this:

content = await page.content()
links = await page.locator("a").all()

It’s been a while since I used Python daily, and I don’t know how to correctly set the mock for page from the example. The content is an async method, and the locator is not.

Environment:

Base
Platform:   darwin
OS:         posix
Python:     3.11.9
Path:       /nix/store/7rr2jhwcm4z0r727q4lpfkbvfmjcg07k-python3-3.11.9
Executable: /nix/store/7rr2jhwcm4z0r727q4lpfkbvfmjcg07k-python3-3.11.9/bin/python3.11

pytest                  7.4.3      pytest: simple powerful testing with Python
pytest-asyncio          0.21.1     Pytest support for asyncio

I went through the docs, and couldn’t find an answer. After some jumping between TypeError: object MagicMock can't be used in 'await' expression and AttributeError: 'coroutine' object has no attribute 'all' I came up with this snippet:

from unittest.mock import AsyncMock

@pytest.mark.asyncio
async def test_async_mocks():
    locator = AsyncMock()
    page = AsyncMock()

    locator.all = AsyncMock(return_value="Hello, there")
    
    page.content = AsyncMock(return_value="Hello")
    page.locator = lambda *args: locator

    assert "Hello" == await page.content()
    assert "Hello, there" == await page.locator("a").all()

The lambda looks like a hack, since I haven’t seen any examples similar to this in the documentation. How can I set up this mock with mock API?