pytest - module discovery not working from virtual env

[omriman12]

Following the example shown here: https://docs.pytest.org/en/stable/example/simple.html#package-directory-level-fixtures-setups

I have set a testing app with the following(as shown in the link):

content of a/conftest.py

import pytest

class DB:
    pass

@pytest.fixture(scope="session")
def db():
    return DB()

content of a/test_db.py

def test_a1(db):
    assert 0, db  # to show value

content of a/test_db2.py

def test_a2(db):
    assert 0, db  # to show value

When I run pytest -s using the global pytest installed on my pc I get the expected behavior(conftest.py fixture is being discovered and a single instance of DB class is invoked)

But.. when I call the same pytest within a venv I receive an error:

fixture 'db' not found

I have spent hours on hours trying to figure out why, and how to fix it

[RonnyPfannschmidt]

it works for me

(.env) [ronny@ronnyt490 user-test-9014]$ tree
.
└── a
    ├── conftest.py
    ├── __pycache__
    │   ├── conftest.cpython-39-pytest-6.2.4.pyc
    │   ├── test_db2.cpython-39-pytest-6.2.4.pyc
    │   └── test_db.cpython-39-pytest-6.2.4.pyc
    ├── test_db2.py
    └── test_db.py

2 directories, 6 files
(.env) [ronny@ronnyt490 user-test-9014]$ pytest -v
======================================================================== test session starts ========================================================================
platform linux -- Python 3.9.6, pytest-6.2.4, py-1.10.0, pluggy-0.13.1 -- /home/ronny/Projects/pytest-dev/user-test-9014/.env/bin/python
cachedir: .pytest_cache
rootdir: /home/ronny/Projects/pytest-dev/user-test-9014
collected 2 items                                                                                                                                                   

a/test_db.py::test_a1 FAILED                                                                                                                                  [ 50%]
a/test_db2.py::test_a2 FAILED                                                                                                                                 [100%]

============================================================================= FAILURES ==============================================================================
______________________________________________________________________________ test_a1 ______________________________________________________________________________

db = <conftest.DB object at 0x7fd4ab32ae80>

    def test_a1(db):
>       assert 0, db  # to show value
E       AssertionError: <conftest.DB object at 0x7fd4ab32ae80>
E       assert 0

a/test_db.py:2: AssertionError
______________________________________________________________________________ test_a2 ______________________________________________________________________________

db = <conftest.DB object at 0x7fd4ab32ae80>

    def test_a2(db):
>       assert 0, db  # to show value
E       AssertionError: <conftest.DB object at 0x7fd4ab32ae80>
E       assert 0

a/test_db2.py:2: AssertionError
====================================================================== short test summary info ======================================================================
FAILED a/test_db.py::test_a1 - AssertionError: <conftest.DB object at 0x7fd4ab32ae80>
FAILED a/test_db2.py::test_a2 - AssertionError: <conftest.DB object at 0x7fd4ab32ae80>
========================================================================= 2 failed in 0.02s =========================================================================

please provide your outputs for the invocations