Add fs_module to conftest.py for plugin tests

- remove installing pyfakefs from CI
- fixes #687

.github/workflows/pythonpackage.yml

@@ -79,7 +79,6 @@ jobs:
       run: |
         pip install wheel
         pip install -r requirements.txt
-        pip install .
     - name: Run unit tests without extra packages as non-root user
       run: |
         export TEST_REAL_FS=1

CHANGES.md

@@ -7,6 +7,10 @@ The released versions correspond to PyPi releases.
 * added support for `opener` argument in `open`, which is used in `tempfile`
   in Python 3.11 since beta 4 (see [#686](../../issues/686))
 
+### Infrastructure
+* make sure tests run without `pyfakefs` installed as a package
+  (see [#687](../../issues/687))
+
 ## [Version 4.6.0](https://pypi.python.org/pypi/pyfakefs/4.6.0) (2022-07-12)
 Adds support for Python 3.11, removes support for Python 3.6, changes root 
 path behavior under Windows. 

pyfakefs/pytest_tests/conftest.py

@@ -20,7 +20,7 @@
 from pyfakefs.fake_filesystem_unittest import Patcher
 
 # import the fs fixture to be visible if pyfakefs is not installed
-from pyfakefs.pytest_plugin import fs  # noqa: F401
+from pyfakefs.pytest_plugin import fs, fs_module  # noqa: F401
 
 from pyfakefs.pytest_tests import example  # noqa: E402
 

requirements.txt

@@ -1 +1 @@
-pytest>=2.8.6
+pytest>=3.0.0