The modern virtual environment structure does not allow us to enable
"fake user site" while disabling the global site, so we need to do more
fine-grained configuration to correctly set up test environments for
each test case.
With this done, we can also properly support the stdlib venv ad the test
environment backend, since it basically works identically with modern
virtualenv. The incompatible_with_test_venv is thus removed.
The old INITools tests rely on setup.py, which relies on distutils and
generates a ton of issues. Build fake wheels directly to avoid dealing
with them.
The pip-specific Path implementation has been removed, and all its
usages replaced by pathlib.Path. The tmpdir and tmpdir_factory fixtures
are also removed, and all usages are replaced by tmp_path and
tmp_path_factory, which use pathlib.Path.
The pip() function now also accepts pathlib.Path so we don't need to put
str() everywhere. Path arguments are coerced with os.fspath() into str.
Our isolation logic for venv isn't correct and that is causing these
tests to fail. The culprits for this are:
tests/lib/venv.py::VirtualEnvironment.user_site_packages
tests/lib/venv.py::VirtualEnvironment.sitecustomize
Both these together are supposed to create an environment to isolate the
tests. However, they were written for virtualenv and make assumptions
that are not true for environments created with venv. Until we can fix
VirtualEnvironment to properly isolate the test from the underlying test
environment when using venv, these tests will continue to fail.
This is blocking an important bugfix for users facing issues with since
pip is installing packages into `--user` when run in a venv, even when
`--user` isn't visible from that environment.
As a temporary band-aid for this problem, I'm skipping these tests to
unblock us from shipping the bugfix for the aforementioned issue.
The test isolation logic should be fixed to work for venv. Once such a
fix is made, this commit should be reverted.
Add a new testsuite option `--use-venv` to enable the use of `venv`
for creating a test virtual environment. The option is opt-in because
creating a `venv` environment does not work right when running under a
`virtualenv`; which is why `tox-venv` must be used in combination with
tox.
- cleanup virtualenv creation code
- ensure all testing virtual environments use a recent version
of setuptools / wheel, making it easier to switch to custom
versions of those, as well as reducing network accesses
- reduce size of testing virtual environment, slightly speeding
up the testsuite
importing it prevent to debug other packages with `-W error` as the
deprecation warning will raise.
Though there is still imp imported from a few vendorized packages,
and for other purposes than cache_from_source.