Adequate venv fixtures to the latest change in virtualenv

Since version v20.23.0, `virtualenv` will no longer include `wheel` and
`setuptools` in the created folders.

Some tests in the setuptools test suite assume that these packages are
always present. So we need to adequate these tests.

setuptools/tests/fixtures.py

@@ -105,6 +105,8 @@ def venv(tmp_path, setuptools_wheel):
     """Virtual env with the version of setuptools under test installed"""
     env = environment.VirtualEnv()
     env.root = path.Path(tmp_path / 'venv')
+    env.create_opts = ['--no-setuptools', '--wheel=bundle']
+    # TODO: Use `--no-wheel` when setuptools implements its own bdist_wheel
     env.req = str(setuptools_wheel)
     # In some environments (eg. downstream distro packaging),
     # where tox isn't used to run tests and PYTHONPATH is set to point to
@@ -125,7 +127,7 @@ def venv_without_setuptools(tmp_path):
     """Virtual env without any version of setuptools installed"""
     env = environment.VirtualEnv()
     env.root = path.Path(tmp_path / 'venv_without_setuptools')
-    env.create_opts = ['--no-setuptools']
+    env.create_opts = ['--no-setuptools', '--no-wheel']
     env.ensure_env()
     return env
 

setuptools/tests/test_virtualenv.py

@@ -174,8 +174,8 @@ def sdist(distname, version):
 
 
 def test_test_command_install_requirements(venv, tmpdir, tmpdir_cwd):
-    # Ensure pip/wheel packages are installed.
-    venv.run(["python", "-c", "__import__('pkg_resources').require(['pip', 'wheel'])"])
+    # Ensure pip is installed.
+    venv.run(["python", "-c", "import pip"])
     # disable index URL so bits and bobs aren't requested from PyPI
     with contexts.environment(PYTHONPATH=None, PIP_NO_INDEX="1"):
         _check_test_command_install_requirements(venv, tmpdir)