Add package scoped fixtures

[mosoto]

Session level scoping is great for expensive setup steps but it doesn't cleanup until the end of the test run. If you are testing multiple packages with conflicting setups you are forced to invoke py.test multiple times, once per package. We would love to have package scoped fixtures - run setup/teardown once per package.

e.g.
With directory structure:

/package1/conftest.py
/package1/test_package1.py
/package2/conftest.py
/package2/test_package2.py

a package scoped fixture defined in /package1/conftest.py would run setup before running the tests in the package1 directory and teardown immediately after finishing the tests in the package1 directory, before running tests in the package2 directory.

[RonnyPfannschmidt]

bascially this is a request for a new scope,

this currently would have to completely change the structure of collection, so its a major change

[nicoddemus]

this currently would have to completely change the structure of collection

Why do you say that @RonnyPfannschmidt? I think it could follow the usual scoping rules: when a test function requests a package-scoped fixture and it doesn't exist, create it; tests execute as normal, until the nextitem is from a different package in which the case the package-scoped fixture is tear down.

Of course we can't guarantee that for a specific package only one package-scoped fixture will be created for the lifetime of the test session given that plugins like pytest-xdist and pytest-random can change the order of the items, but I think that would be OK and is the same constraint we have with the current scopes.

Just trying to get a clear picture of why you think this would need to change the structure of the collection.

so its a major change

Oh I agree. 👍

[jonozzz]

We have a similar test structure:

suite1/__init__.py
suite1/conftest.py
suite1/test_1.py
suite1/test_2.py

suite2/__init__.py
suite2/conftest.py
suite2/test_1.py
suite2/test_2.py

# suite1/conftest.py
@pytest.fixture(scope='session', autouse=True)
def make_items():
    items = respool.get(N)
    yield items
    respool.free(items)

# suite2/conftest.py
@pytest.fixture(scope='session', autouse=True)
def make_items():
    items = respool.get(M)
    yield items
    respool.free(items)

Now the tests in the suite1 require an expensive setup, for instance they pull N items from a shared reservation pool of N+1 items. Then comes suite2 that needs to pull another M (M >> 1) items from the same pool, but there's not enough left because suite1's teardown has not executed yet. All "session" scoped teardowns execute after all tests have been executed.

Is there any chance we can revisit this? I volunteer to help if you point me in the right direction!

[RonnyPfannschmidt]

@nicoddemus currently we have no nodes for folders, so we have no reference point for the setupstate of a package

[nicoddemus]

Closed by #3389