Replace compat.expanduser() with os.path.expanduser()

The upstream bug has been fixed and released in all supported Python
version: https://bugs.python.org/issue14768

src/pip/_internal/configuration.py

@@ -22,7 +22,7 @@ from pip._internal.exceptions import (
     ConfigurationFileCouldNotBeLoaded,
 )
 from pip._internal.utils import appdirs
-from pip._internal.utils.compat import WINDOWS, expanduser
+from pip._internal.utils.compat import WINDOWS
 from pip._internal.utils.misc import ensure_dir, enum
 from pip._internal.utils.typing import MYPY_CHECK_RUNNING
 
@@ -80,7 +80,7 @@ def get_configuration_files():
 
     site_config_file = os.path.join(sys.prefix, CONFIG_BASENAME)
     legacy_config_file = os.path.join(
-        expanduser('~'),
+        os.path.expanduser('~'),
         'pip' if WINDOWS else '.pip',
         CONFIG_BASENAME,
     )

src/pip/_internal/utils/compat.py

@@ -139,19 +139,6 @@ def get_path_uid(path):
     return file_uid
 
 
-def expanduser(path):
-    # type: (str) -> str
-    """
-    Expand ~ and ~user constructions.
-
-    Includes a workaround for https://bugs.python.org/issue14768
-    """
-    expanded = os.path.expanduser(path)
-    if path.startswith('~/') and expanded.startswith('//'):
-        expanded = expanded[1:]
-    return expanded
-
-
 # packages in the stdlib that may have installation metadata, but should not be
 # considered 'installed'.  this theoretically could be determined based on
 # dist.location (py27:`sysconfig.get_paths()['stdlib']`,

src/pip/_internal/utils/misc.py

@@ -28,7 +28,7 @@ from pip._vendor.retrying import retry  # type: ignore
 from pip import __version__
 from pip._internal.exceptions import CommandError
 from pip._internal.locations import get_major_minor_version, site_packages, user_site
-from pip._internal.utils.compat import WINDOWS, expanduser, stdlib_pkgs
+from pip._internal.utils.compat import WINDOWS, stdlib_pkgs
 from pip._internal.utils.typing import MYPY_CHECK_RUNNING, cast
 from pip._internal.utils.virtualenv import (
     running_under_virtualenv,
@@ -302,7 +302,7 @@ def normalize_path(path, resolve_symlinks=True):
     Convert a path to its canonical, case-normalized, absolute version.
 
     """
-    path = expanduser(path)
+    path = os.path.expanduser(path)
     if resolve_symlinks:
         path = os.path.realpath(path)
     else:

tests/unit/test_collector.py

@@ -733,7 +733,7 @@ def test_link_collector_create(
     assert search_scope.index_urls == expected_index_urls
 
 
-@patch('pip._internal.utils.misc.expanduser')
+@patch('os.path.expanduser')
 def test_link_collector_create_find_links_expansion(
     mock_expanduser, tmpdir,
 ):

tests/unit/test_compat.py

@@ -5,12 +5,7 @@ import sys
 import pytest
 
 import pip._internal.utils.compat as pip_compat
-from pip._internal.utils.compat import (
+from pip._internal.utils.compat import console_to_str, get_path_uid, str_to_display
-    console_to_str,
-    expanduser,
-    get_path_uid,
-    str_to_display,
-)
 
 
 def test_get_path_uid():
@@ -127,16 +122,3 @@ def test_console_to_str_warning(monkeypatch):
     monkeypatch.setattr(locale, 'getpreferredencoding', lambda: 'utf-8')
     monkeypatch.setattr(pip_compat.logger, 'warning', check_warning)
     console_to_str(some_bytes)
-
-
-@pytest.mark.parametrize("home,path,expanded", [
-    ("/Users/test", "~", "/Users/test"),
-    ("/Users/test", "~/.cache", "/Users/test/.cache"),
-    # Verify that we are not affected by https://bugs.python.org/issue14768
-    ("/", "~", "/"),
-    ("/", "~/.cache", "/.cache"),
-])
-def test_expanduser(home, path, expanded, monkeypatch):
-    monkeypatch.setenv("HOME", home)
-    monkeypatch.setenv("USERPROFILE", home)
-    assert expanduser(path) == expanded