Make VersionControl.get_netloc_and_auth() a class method.

src/pip/_internal/vcs/__init__.py

@@ -293,7 +293,8 @@ class VersionControl(object):
         """
         raise NotImplementedError
 
-    def get_netloc_and_auth(self, netloc, scheme):
+    @classmethod
+    def get_netloc_and_auth(cls, netloc, scheme):
         """
         Parse the repository URL's netloc, and return the new netloc to use
         along with auth information.

src/pip/_internal/vcs/subversion.py

@@ -92,7 +92,8 @@ class Subversion(VersionControl):
             revision = max(revision, localrev)
         return revision
 
-    def get_netloc_and_auth(self, netloc, scheme):
+    @classmethod
+    def get_netloc_and_auth(cls, netloc, scheme):
         """
         This override allows the auth information to be passed to svn via the
         --username and --password options instead of via the URL.
@@ -100,8 +101,7 @@ class Subversion(VersionControl):
         if scheme == 'ssh':
             # The --username and --password options can't be used for
             # svn+ssh URLs, so keep the auth information in the URL.
-            return super(Subversion, self).get_netloc_and_auth(
-                netloc, scheme)
+            return super(Subversion, cls).get_netloc_and_auth(netloc, scheme)
 
         return split_auth_from_netloc(netloc)
 

tests/unit/test_vcs.py

@@ -206,7 +206,7 @@ def test_git__get_netloc_and_auth(args, expected):
     Test VersionControl.get_netloc_and_auth().
     """
     netloc, scheme = args
-    actual = Git().get_netloc_and_auth(netloc, scheme)
+    actual = Git.get_netloc_and_auth(netloc, scheme)
     assert actual == expected
 
 
@@ -229,7 +229,7 @@ def test_subversion__get_netloc_and_auth(args, expected):
     Test Subversion.get_netloc_and_auth().
     """
     netloc, scheme = args
-    actual = Subversion().get_netloc_and_auth(netloc, scheme)
+    actual = Subversion.get_netloc_and_auth(netloc, scheme)
     assert actual == expected