Remove hardcoded libpython binaries and add debug step

venv/lib/python3.12/site-packages/setuptools/tests/test_virtualenv.py

@@ -0,0 +1,113 @@
+import os
+import subprocess
+import sys
+from urllib.error import URLError
+from urllib.request import urlopen
+
+import pytest
+
+
+@pytest.fixture(autouse=True)
+def pytest_virtualenv_works(venv):
+    """
+    pytest_virtualenv may not work. if it doesn't, skip these
+    tests. See #1284.
+    """
+    venv_prefix = venv.run(["python", "-c", "import sys; print(sys.prefix)"]).strip()
+    if venv_prefix == sys.prefix:
+        pytest.skip("virtualenv is broken (see pypa/setuptools#1284)")
+
+
+def test_clean_env_install(venv_without_setuptools, setuptools_wheel):
+    """
+    Check setuptools can be installed in a clean environment.
+    """
+    cmd = ["python", "-m", "pip", "install", str(setuptools_wheel)]
+    venv_without_setuptools.run(cmd)
+
+
+def access_pypi():
+    # Detect if tests are being run without connectivity
+    if not os.environ.get('NETWORK_REQUIRED', False):  # pragma: nocover
+        try:
+            urlopen('https://pypi.org', timeout=1)
+        except URLError:
+            # No network, disable most of these tests
+            return False
+
+    return True
+
+
+@pytest.mark.skipif(
+    'platform.python_implementation() == "PyPy"',
+    reason="https://github.com/pypa/setuptools/pull/2865#issuecomment-965834995",
+)
+@pytest.mark.skipif(not access_pypi(), reason="no network")
+# ^-- Even when it is not necessary to install a different version of `pip`
+#     the build process will still try to download `wheel`, see #3147 and #2986.
+@pytest.mark.parametrize(
+    'pip_version',
+    [
+        None,
+        pytest.param(
+            'pip<20.1',
+            marks=pytest.mark.xfail(
+                'sys.version_info >= (3, 12)',
+                reason="pip 23.1.2 required for Python 3.12 and later",
+            ),
+        ),
+        pytest.param(
+            'pip<21',
+            marks=pytest.mark.xfail(
+                'sys.version_info >= (3, 12)',
+                reason="pip 23.1.2 required for Python 3.12 and later",
+            ),
+        ),
+        pytest.param(
+            'pip<22',
+            marks=pytest.mark.xfail(
+                'sys.version_info >= (3, 12)',
+                reason="pip 23.1.2 required for Python 3.12 and later",
+            ),
+        ),
+        pytest.param(
+            'pip<23',
+            marks=pytest.mark.xfail(
+                'sys.version_info >= (3, 12)',
+                reason="pip 23.1.2 required for Python 3.12 and later",
+            ),
+        ),
+        pytest.param(
+            'https://github.com/pypa/pip/archive/main.zip',
+            marks=pytest.mark.xfail(reason='#2975'),
+        ),
+    ],
+)
+def test_pip_upgrade_from_source(
+    pip_version, venv_without_setuptools, setuptools_wheel, setuptools_sdist
+):
+    """
+    Check pip can upgrade setuptools from source.
+    """
+    # Install pip/wheel, in a venv without setuptools (as it
+    # should not be needed for bootstrapping from source)
+    venv = venv_without_setuptools
+    venv.run(["pip", "install", "-U", "wheel"])
+    if pip_version is not None:
+        venv.run(["python", "-m", "pip", "install", "-U", pip_version, "--retries=1"])
+    with pytest.raises(subprocess.CalledProcessError):
+        # Meta-test to make sure setuptools is not installed
+        venv.run(["python", "-c", "import setuptools"])
+
+    # Then install from wheel.
+    venv.run(["pip", "install", str(setuptools_wheel)])
+    # And finally try to upgrade from source.
+    venv.run(["pip", "install", "--no-cache-dir", "--upgrade", str(setuptools_sdist)])
+
+
+def test_no_missing_dependencies(bare_venv, request):
+    """
+    Quick and dirty test to ensure all external dependencies are vendored.
+    """
+    setuptools_dir = request.config.rootdir
+    bare_venv.run(['python', 'setup.py', '--help'], cwd=setuptools_dir)