Remove workaround for pypa/pip#4106. Fixes #43.

CHANGES.rst

@@ -1,3 +1,9 @@
+v6.2.0
+------
+
+#43: Removed workaround for pip 4106. Project now requires
+pip 19.3 or later.
+
 v6.1.0
 ------
 

pip_run/deps.py

@@ -48,42 +48,13 @@ def _installable(args):
 def load(*args):
     target = tempfile.mkdtemp(prefix='pip-run-')
     cmd = (sys.executable, '-m', 'pip', 'install', '-t', target) + args
-    with _patch_prefix():
-        _installable(args) and subprocess.check_call(cmd)
+    _installable(args) and subprocess.check_call(cmd)
     try:
         yield target
     finally:
         shutil.rmtree(target)
 
 
-def _needs_pip_4106_workaround():
-    """
-    Detect if the environment is configured with a prefix, as
-    the workaround is only required under those conditions.
-    """
-    import distutils.dist
-
-    dist = distutils.dist.Distribution()
-    dist.parse_config_files()
-    return 'prefix' in dist.get_option_dict('install')
-
-
-@contextlib.contextmanager
-def _patch_prefix():
-    """
-    To workaround pypa/pip#4106, override the system prefix with
-    a user prefix, restoring the original file after.
-    """
-    if not _needs_pip_4106_workaround():
-        yield
-        return
-    cfg_fn = os.path.expanduser('~/.pydistutils.cfg')
-    with _save_file(cfg_fn):
-        with open(cfg_fn, 'w') as cfg:
-            cfg.write('[install]\nprefix=\n')
-        yield
-
-
 @contextlib.contextmanager
 def _save_file(filename):
     """

setup.cfg

@@ -21,7 +21,7 @@ packages = find:
 include_package_data = true
 py_modules = pip-run
 python_requires = >=2.7
-install_requires = pip
+install_requires = pip >= 19.3
 setup_requires = setuptools_scm >= 1.15.0
 
 [options.extras_require]