Remove tests guaranteeing that (vendored) dependencies can be installed without setuptools.

In a PEP 517 world without distutils, packagers will need to find another way to build and supply the dependencies

setuptools/tests/test_integration.py

@@ -6,11 +6,6 @@ Try to install a few packages.
 import glob
 import os
 import sys
-import re
-import subprocess
-import functools
-import tarfile
-import zipfile
 import urllib.request
 
 import pytest
@@ -117,54 +112,3 @@ def test_pyuri(install_context):
 
     # The package data should be installed.
     assert os.path.exists(os.path.join(pyuri.location, 'pyuri', 'uri.regex'))
-
-
-build_deps = ['appdirs', 'packaging', 'pyparsing', 'six']
-
-
-@pytest.mark.parametrize("build_dep", build_deps)
-def test_build_deps_on_distutils(request, tmpdir_factory, build_dep):
-    """
-    All setuptools build dependencies must build without
-    setuptools.
-    """
-    if 'pyparsing' in build_dep:
-        pytest.xfail(reason="Project imports setuptools unconditionally")
-    build_target = tmpdir_factory.mktemp('source')
-    build_dir = download_and_extract(request, build_dep, build_target)
-    install_target = tmpdir_factory.mktemp('target')
-    output = install(build_dir, install_target)
-    for line in output.splitlines():
-        match = re.search('Unknown distribution option: (.*)', line)
-        allowed_unknowns = [
-            'test_suite',
-            'tests_require',
-            'python_requires',
-            'install_requires',
-            'long_description_content_type',
-        ]
-        assert not match or match.group(1).strip('"\'') in allowed_unknowns
-
-
-def install(pkg_dir, install_dir):
-    with open(os.path.join(pkg_dir, 'setuptools.py'), 'w') as breaker:
-        breaker.write('raise ImportError()')
-    cmd = [sys.executable, 'setup.py', 'install', '--prefix', str(install_dir)]
-    env = dict(os.environ, PYTHONPATH=str(pkg_dir))
-    output = subprocess.check_output(
-        cmd, cwd=pkg_dir, env=env, stderr=subprocess.STDOUT)
-    return output.decode('utf-8')
-
-
-def download_and_extract(request, req, target):
-    cmd = [
-        sys.executable, '-m', 'pip', 'download', '--no-deps',
-        '--no-binary', ':all:', req,
-    ]
-    output = subprocess.check_output(cmd, encoding='utf-8')
-    filename = re.search('Saved (.*)', output).group(1)
-    request.addfinalizer(functools.partial(os.remove, filename))
-    opener = zipfile.ZipFile if filename.endswith('.zip') else tarfile.open
-    with opener(filename) as archive:
-        archive.extractall(target)
-    return os.path.join(target, os.listdir(target)[0])