--- a/lib/python3.8/site-packages/pip/_internal/vcs/versioncontrol.py	Mon Jul 27 03:47:31 2020 -0400
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,700 +0,0 @@
-"""Handles all VCS (version control) support"""
-
-from __future__ import absolute_import
-
-import errno
-import logging
-import os
-import shutil
-import sys
-
-from pip._vendor import pkg_resources
-from pip._vendor.six.moves.urllib import parse as urllib_parse
-
-from pip._internal.exceptions import BadCommand
-from pip._internal.utils.compat import samefile
-from pip._internal.utils.misc import (
-    ask_path_exists,
-    backup_dir,
-    display_path,
-    hide_url,
-    hide_value,
-    rmtree,
-)
-from pip._internal.utils.subprocess import call_subprocess, make_command
-from pip._internal.utils.typing import MYPY_CHECK_RUNNING
-from pip._internal.utils.urls import get_url_scheme
-
-if MYPY_CHECK_RUNNING:
-    from typing import (
-        Any, Dict, Iterable, Iterator, List, Mapping, Optional, Text, Tuple,
-        Type, Union
-    )
-    from pip._internal.utils.ui import SpinnerInterface
-    from pip._internal.utils.misc import HiddenText
-    from pip._internal.utils.subprocess import CommandArgs
-
-    AuthInfo = Tuple[Optional[str], Optional[str]]
-
-
-__all__ = ['vcs']
-
-
-logger = logging.getLogger(__name__)
-
-
-def is_url(name):
-    # type: (Union[str, Text]) -> bool
-    """
-    Return true if the name looks like a URL.
-    """
-    scheme = get_url_scheme(name)
-    if scheme is None:
-        return False
-    return scheme in ['http', 'https', 'file', 'ftp'] + vcs.all_schemes
-
-
-def make_vcs_requirement_url(repo_url, rev, project_name, subdir=None):
-    # type: (str, str, str, Optional[str]) -> str
-    """
-    Return the URL for a VCS requirement.
-
-    Args:
-      repo_url: the remote VCS url, with any needed VCS prefix (e.g. "git+").
-      project_name: the (unescaped) project name.
-    """
-    egg_project_name = pkg_resources.to_filename(project_name)
-    req = '{}@{}#egg={}'.format(repo_url, rev, egg_project_name)
-    if subdir:
-        req += '&subdirectory={}'.format(subdir)
-
-    return req
-
-
-def find_path_to_setup_from_repo_root(location, repo_root):
-    # type: (str, str) -> Optional[str]
-    """
-    Find the path to `setup.py` by searching up the filesystem from `location`.
-    Return the path to `setup.py` relative to `repo_root`.
-    Return None if `setup.py` is in `repo_root` or cannot be found.
-    """
-    # find setup.py
-    orig_location = location
-    while not os.path.exists(os.path.join(location, 'setup.py')):
-        last_location = location
-        location = os.path.dirname(location)
-        if location == last_location:
-            # We've traversed up to the root of the filesystem without
-            # finding setup.py
-            logger.warning(
-                "Could not find setup.py for directory %s (tried all "
-                "parent directories)",
-                orig_location,
-            )
-            return None
-
-    if samefile(repo_root, location):
-        return None
-
-    return os.path.relpath(location, repo_root)
-
-
-class RemoteNotFoundError(Exception):
-    pass
-
-
-class RevOptions(object):
-
-    """
-    Encapsulates a VCS-specific revision to install, along with any VCS
-    install options.
-
-    Instances of this class should be treated as if immutable.
-    """
-
-    def __init__(
-        self,
-        vc_class,  # type: Type[VersionControl]
-        rev=None,  # type: Optional[str]
-        extra_args=None,  # type: Optional[CommandArgs]
-    ):
-        # type: (...) -> None
-        """
-        Args:
-          vc_class: a VersionControl subclass.
-          rev: the name of the revision to install.
-          extra_args: a list of extra options.
-        """
-        if extra_args is None:
-            extra_args = []
-
-        self.extra_args = extra_args
-        self.rev = rev
-        self.vc_class = vc_class
-        self.branch_name = None  # type: Optional[str]
-
-    def __repr__(self):
-        # type: () -> str
-        return '<RevOptions {}: rev={!r}>'.format(self.vc_class.name, self.rev)
-
-    @property
-    def arg_rev(self):
-        # type: () -> Optional[str]
-        if self.rev is None:
-            return self.vc_class.default_arg_rev
-
-        return self.rev
-
-    def to_args(self):
-        # type: () -> CommandArgs
-        """
-        Return the VCS-specific command arguments.
-        """
-        args = []  # type: CommandArgs
-        rev = self.arg_rev
-        if rev is not None:
-            args += self.vc_class.get_base_rev_args(rev)
-        args += self.extra_args
-
-        return args
-
-    def to_display(self):
-        # type: () -> str
-        if not self.rev:
-            return ''
-
-        return ' (to revision {})'.format(self.rev)
-
-    def make_new(self, rev):
-        # type: (str) -> RevOptions
-        """
-        Make a copy of the current instance, but with a new rev.
-
-        Args:
-          rev: the name of the revision for the new object.
-        """
-        return self.vc_class.make_rev_options(rev, extra_args=self.extra_args)
-
-
-class VcsSupport(object):
-    _registry = {}  # type: Dict[str, VersionControl]
-    schemes = ['ssh', 'git', 'hg', 'bzr', 'sftp', 'svn']
-
-    def __init__(self):
-        # type: () -> None
-        # Register more schemes with urlparse for various version control
-        # systems
-        urllib_parse.uses_netloc.extend(self.schemes)
-        # Python >= 2.7.4, 3.3 doesn't have uses_fragment
-        if getattr(urllib_parse, 'uses_fragment', None):
-            urllib_parse.uses_fragment.extend(self.schemes)
-        super(VcsSupport, self).__init__()
-
-    def __iter__(self):
-        # type: () -> Iterator[str]
-        return self._registry.__iter__()
-
-    @property
-    def backends(self):
-        # type: () -> List[VersionControl]
-        return list(self._registry.values())
-
-    @property
-    def dirnames(self):
-        # type: () -> List[str]
-        return [backend.dirname for backend in self.backends]
-
-    @property
-    def all_schemes(self):
-        # type: () -> List[str]
-        schemes = []  # type: List[str]
-        for backend in self.backends:
-            schemes.extend(backend.schemes)
-        return schemes
-
-    def register(self, cls):
-        # type: (Type[VersionControl]) -> None
-        if not hasattr(cls, 'name'):
-            logger.warning('Cannot register VCS %s', cls.__name__)
-            return
-        if cls.name not in self._registry:
-            self._registry[cls.name] = cls()
-            logger.debug('Registered VCS backend: %s', cls.name)
-
-    def unregister(self, name):
-        # type: (str) -> None
-        if name in self._registry:
-            del self._registry[name]
-
-    def get_backend_for_dir(self, location):
-        # type: (str) -> Optional[VersionControl]
-        """
-        Return a VersionControl object if a repository of that type is found
-        at the given directory.
-        """
-        for vcs_backend in self._registry.values():
-            if vcs_backend.controls_location(location):
-                logger.debug('Determine that %s uses VCS: %s',
-                             location, vcs_backend.name)
-                return vcs_backend
-        return None
-
-    def get_backend_for_scheme(self, scheme):
-        # type: (str) -> Optional[VersionControl]
-        """
-        Return a VersionControl object or None.
-        """
-        for vcs_backend in self._registry.values():
-            if scheme in vcs_backend.schemes:
-                return vcs_backend
-        return None
-
-    def get_backend(self, name):
-        # type: (str) -> Optional[VersionControl]
-        """
-        Return a VersionControl object or None.
-        """
-        name = name.lower()
-        return self._registry.get(name)
-
-
-vcs = VcsSupport()
-
-
-class VersionControl(object):
-    name = ''
-    dirname = ''
-    repo_name = ''
-    # List of supported schemes for this Version Control
-    schemes = ()  # type: Tuple[str, ...]
-    # Iterable of environment variable names to pass to call_subprocess().
-    unset_environ = ()  # type: Tuple[str, ...]
-    default_arg_rev = None  # type: Optional[str]
-
-    @classmethod
-    def should_add_vcs_url_prefix(cls, remote_url):
-        # type: (str) -> bool
-        """
-        Return whether the vcs prefix (e.g. "git+") should be added to a
-        repository's remote url when used in a requirement.
-        """
-        return not remote_url.lower().startswith('{}:'.format(cls.name))
-
-    @classmethod
-    def get_subdirectory(cls, location):
-        # type: (str) -> Optional[str]
-        """
-        Return the path to setup.py, relative to the repo root.
-        Return None if setup.py is in the repo root.
-        """
-        return None
-
-    @classmethod
-    def get_requirement_revision(cls, repo_dir):
-        # type: (str) -> str
-        """
-        Return the revision string that should be used in a requirement.
-        """
-        return cls.get_revision(repo_dir)
-
-    @classmethod
-    def get_src_requirement(cls, repo_dir, project_name):
-        # type: (str, str) -> Optional[str]
-        """
-        Return the requirement string to use to redownload the files
-        currently at the given repository directory.
-
-        Args:
-          project_name: the (unescaped) project name.
-
-        The return value has a form similar to the following:
-
-            {repository_url}@{revision}#egg={project_name}
-        """
-        repo_url = cls.get_remote_url(repo_dir)
-        if repo_url is None:
-            return None
-
-        if cls.should_add_vcs_url_prefix(repo_url):
-            repo_url = '{}+{}'.format(cls.name, repo_url)
-
-        revision = cls.get_requirement_revision(repo_dir)
-        subdir = cls.get_subdirectory(repo_dir)
-        req = make_vcs_requirement_url(repo_url, revision, project_name,
-                                       subdir=subdir)
-
-        return req
-
-    @staticmethod
-    def get_base_rev_args(rev):
-        # type: (str) -> List[str]
-        """
-        Return the base revision arguments for a vcs command.
-
-        Args:
-          rev: the name of a revision to install.  Cannot be None.
-        """
-        raise NotImplementedError
-
-    def is_immutable_rev_checkout(self, url, dest):
-        # type: (str, str) -> bool
-        """
-        Return true if the commit hash checked out at dest matches
-        the revision in url.
-
-        Always return False, if the VCS does not support immutable commit
-        hashes.
-
-        This method does not check if there are local uncommitted changes
-        in dest after checkout, as pip currently has no use case for that.
-        """
-        return False
-
-    @classmethod
-    def make_rev_options(cls, rev=None, extra_args=None):
-        # type: (Optional[str], Optional[CommandArgs]) -> RevOptions
-        """
-        Return a RevOptions object.
-
-        Args:
-          rev: the name of a revision to install.
-          extra_args: a list of extra options.
-        """
-        return RevOptions(cls, rev, extra_args=extra_args)
-
-    @classmethod
-    def _is_local_repository(cls, repo):
-        # type: (str) -> bool
-        """
-           posix absolute paths start with os.path.sep,
-           win32 ones start with drive (like c:\\folder)
-        """
-        drive, tail = os.path.splitdrive(repo)
-        return repo.startswith(os.path.sep) or bool(drive)
-
-    def export(self, location, url):
-        # type: (str, HiddenText) -> None
-        """
-        Export the repository at the url to the destination location
-        i.e. only download the files, without vcs informations
-
-        :param url: the repository URL starting with a vcs prefix.
-        """
-        raise NotImplementedError
-
-    @classmethod
-    def get_netloc_and_auth(cls, netloc, scheme):
-        # type: (str, str) -> Tuple[str, Tuple[Optional[str], Optional[str]]]
-        """
-        Parse the repository URL's netloc, and return the new netloc to use
-        along with auth information.
-
-        Args:
-          netloc: the original repository URL netloc.
-          scheme: the repository URL's scheme without the vcs prefix.
-
-        This is mainly for the Subversion class to override, so that auth
-        information can be provided via the --username and --password options
-        instead of through the URL.  For other subclasses like Git without
-        such an option, auth information must stay in the URL.
-
-        Returns: (netloc, (username, password)).
-        """
-        return netloc, (None, None)
-
-    @classmethod
-    def get_url_rev_and_auth(cls, url):
-        # type: (str) -> Tuple[str, Optional[str], AuthInfo]
-        """
-        Parse the repository URL to use, and return the URL, revision,
-        and auth info to use.
-
-        Returns: (url, rev, (username, password)).
-        """
-        scheme, netloc, path, query, frag = urllib_parse.urlsplit(url)
-        if '+' not in scheme:
-            raise ValueError(
-                "Sorry, {!r} is a malformed VCS url. "
-                "The format is <vcs>+<protocol>://<url>, "
-                "e.g. svn+http://myrepo/svn/MyApp#egg=MyApp".format(url)
-            )
-        # Remove the vcs prefix.
-        scheme = scheme.split('+', 1)[1]
-        netloc, user_pass = cls.get_netloc_and_auth(netloc, scheme)
-        rev = None
-        if '@' in path:
-            path, rev = path.rsplit('@', 1)
-        url = urllib_parse.urlunsplit((scheme, netloc, path, query, ''))
-        return url, rev, user_pass
-
-    @staticmethod
-    def make_rev_args(username, password):
-        # type: (Optional[str], Optional[HiddenText]) -> CommandArgs
-        """
-        Return the RevOptions "extra arguments" to use in obtain().
-        """
-        return []
-
-    def get_url_rev_options(self, url):
-        # type: (HiddenText) -> Tuple[HiddenText, RevOptions]
-        """
-        Return the URL and RevOptions object to use in obtain() and in
-        some cases export(), as a tuple (url, rev_options).
-        """
-        secret_url, rev, user_pass = self.get_url_rev_and_auth(url.secret)
-        username, secret_password = user_pass
-        password = None  # type: Optional[HiddenText]
-        if secret_password is not None:
-            password = hide_value(secret_password)
-        extra_args = self.make_rev_args(username, password)
-        rev_options = self.make_rev_options(rev, extra_args=extra_args)
-
-        return hide_url(secret_url), rev_options
-
-    @staticmethod
-    def normalize_url(url):
-        # type: (str) -> str
-        """
-        Normalize a URL for comparison by unquoting it and removing any
-        trailing slash.
-        """
-        return urllib_parse.unquote(url).rstrip('/')
-
-    @classmethod
-    def compare_urls(cls, url1, url2):
-        # type: (str, str) -> bool
-        """
-        Compare two repo URLs for identity, ignoring incidental differences.
-        """
-        return (cls.normalize_url(url1) == cls.normalize_url(url2))
-
-    def fetch_new(self, dest, url, rev_options):
-        # type: (str, HiddenText, RevOptions) -> None
-        """
-        Fetch a revision from a repository, in the case that this is the
-        first fetch from the repository.
-
-        Args:
-          dest: the directory to fetch the repository to.
-          rev_options: a RevOptions object.
-        """
-        raise NotImplementedError
-
-    def switch(self, dest, url, rev_options):
-        # type: (str, HiddenText, RevOptions) -> None
-        """
-        Switch the repo at ``dest`` to point to ``URL``.
-
-        Args:
-          rev_options: a RevOptions object.
-        """
-        raise NotImplementedError
-
-    def update(self, dest, url, rev_options):
-        # type: (str, HiddenText, RevOptions) -> None
-        """
-        Update an already-existing repo to the given ``rev_options``.
-
-        Args:
-          rev_options: a RevOptions object.
-        """
-        raise NotImplementedError
-
-    @classmethod
-    def is_commit_id_equal(cls, dest, name):
-        # type: (str, Optional[str]) -> bool
-        """
-        Return whether the id of the current commit equals the given name.
-
-        Args:
-          dest: the repository directory.
-          name: a string name.
-        """
-        raise NotImplementedError
-
-    def obtain(self, dest, url):
-        # type: (str, HiddenText) -> None
-        """
-        Install or update in editable mode the package represented by this
-        VersionControl object.
-
-        :param dest: the repository directory in which to install or update.
-        :param url: the repository URL starting with a vcs prefix.
-        """
-        url, rev_options = self.get_url_rev_options(url)
-
-        if not os.path.exists(dest):
-            self.fetch_new(dest, url, rev_options)
-            return
-
-        rev_display = rev_options.to_display()
-        if self.is_repository_directory(dest):
-            existing_url = self.get_remote_url(dest)
-            if self.compare_urls(existing_url, url.secret):
-                logger.debug(
-                    '%s in %s exists, and has correct URL (%s)',
-                    self.repo_name.title(),
-                    display_path(dest),
-                    url,
-                )
-                if not self.is_commit_id_equal(dest, rev_options.rev):
-                    logger.info(
-                        'Updating %s %s%s',
-                        display_path(dest),
-                        self.repo_name,
-                        rev_display,
-                    )
-                    self.update(dest, url, rev_options)
-                else:
-                    logger.info('Skipping because already up-to-date.')
-                return
-
-            logger.warning(
-                '%s %s in %s exists with URL %s',
-                self.name,
-                self.repo_name,
-                display_path(dest),
-                existing_url,
-            )
-            prompt = ('(s)witch, (i)gnore, (w)ipe, (b)ackup ',
-                      ('s', 'i', 'w', 'b'))
-        else:
-            logger.warning(
-                'Directory %s already exists, and is not a %s %s.',
-                dest,
-                self.name,
-                self.repo_name,
-            )
-            # https://github.com/python/mypy/issues/1174
-            prompt = ('(i)gnore, (w)ipe, (b)ackup ',  # type: ignore
-                      ('i', 'w', 'b'))
-
-        logger.warning(
-            'The plan is to install the %s repository %s',
-            self.name,
-            url,
-        )
-        response = ask_path_exists('What to do?  %s' % prompt[0], prompt[1])
-
-        if response == 'a':
-            sys.exit(-1)
-
-        if response == 'w':
-            logger.warning('Deleting %s', display_path(dest))
-            rmtree(dest)
-            self.fetch_new(dest, url, rev_options)
-            return
-
-        if response == 'b':
-            dest_dir = backup_dir(dest)
-            logger.warning(
-                'Backing up %s to %s', display_path(dest), dest_dir,
-            )
-            shutil.move(dest, dest_dir)
-            self.fetch_new(dest, url, rev_options)
-            return
-
-        # Do nothing if the response is "i".
-        if response == 's':
-            logger.info(
-                'Switching %s %s to %s%s',
-                self.repo_name,
-                display_path(dest),
-                url,
-                rev_display,
-            )
-            self.switch(dest, url, rev_options)
-
-    def unpack(self, location, url):
-        # type: (str, HiddenText) -> None
-        """
-        Clean up current location and download the url repository
-        (and vcs infos) into location
-
-        :param url: the repository URL starting with a vcs prefix.
-        """
-        if os.path.exists(location):
-            rmtree(location)
-        self.obtain(location, url=url)
-
-    @classmethod
-    def get_remote_url(cls, location):
-        # type: (str) -> str
-        """
-        Return the url used at location
-
-        Raises RemoteNotFoundError if the repository does not have a remote
-        url configured.
-        """
-        raise NotImplementedError
-
-    @classmethod
-    def get_revision(cls, location):
-        # type: (str) -> str
-        """
-        Return the current commit id of the files at the given location.
-        """
-        raise NotImplementedError
-
-    @classmethod
-    def run_command(
-        cls,
-        cmd,  # type: Union[List[str], CommandArgs]
-        show_stdout=True,  # type: bool
-        cwd=None,  # type: Optional[str]
-        on_returncode='raise',  # type: str
-        extra_ok_returncodes=None,  # type: Optional[Iterable[int]]
-        command_desc=None,  # type: Optional[str]
-        extra_environ=None,  # type: Optional[Mapping[str, Any]]
-        spinner=None,  # type: Optional[SpinnerInterface]
-        log_failed_cmd=True  # type: bool
-    ):
-        # type: (...) -> Text
-        """
-        Run a VCS subcommand
-        This is simply a wrapper around call_subprocess that adds the VCS
-        command name, and checks that the VCS is available
-        """
-        cmd = make_command(cls.name, *cmd)
-        try:
-            return call_subprocess(cmd, show_stdout, cwd,
-                                   on_returncode=on_returncode,
-                                   extra_ok_returncodes=extra_ok_returncodes,
-                                   command_desc=command_desc,
-                                   extra_environ=extra_environ,
-                                   unset_environ=cls.unset_environ,
-                                   spinner=spinner,
-                                   log_failed_cmd=log_failed_cmd)
-        except OSError as e:
-            # errno.ENOENT = no such file or directory
-            # In other words, the VCS executable isn't available
-            if e.errno == errno.ENOENT:
-                raise BadCommand(
-                    'Cannot find command %r - do you have '
-                    '%r installed and in your '
-                    'PATH?' % (cls.name, cls.name))
-            else:
-                raise  # re-raise exception if a different error occurred
-
-    @classmethod
-    def is_repository_directory(cls, path):
-        # type: (str) -> bool
-        """
-        Return whether a directory path is a repository directory.
-        """
-        logger.debug('Checking in %s for %s (%s)...',
-                     path, cls.dirname, cls.name)
-        return os.path.exists(os.path.join(path, cls.dirname))
-
-    @classmethod
-    def controls_location(cls, location):
-        # type: (str) -> bool
-        """
-        Check if a location is controlled by the vcs.
-        It is meant to be overridden to implement smarter detection
-        mechanisms for specific vcs.
-
-        This can do more than is_repository_directory() alone.  For example,
-        the Git override checks that Git is actually available.
-        """
-        return cls.is_repository_directory(location)