723 lines
23 KiB
Python
723 lines
23 KiB
Python
"""Handles all VCS (version control) support"""
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import logging
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import os
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import shutil
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import sys
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import urllib.parse
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from typing import (
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Any,
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Dict,
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Iterable,
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Iterator,
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List,
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Mapping,
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Optional,
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Tuple,
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Type,
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Union,
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)
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from pip._internal.cli.spinners import SpinnerInterface
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from pip._internal.exceptions import BadCommand, InstallationError
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from pip._internal.utils.misc import (
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HiddenText,
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ask_path_exists,
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backup_dir,
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display_path,
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hide_url,
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hide_value,
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is_installable_dir,
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rmtree,
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)
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from pip._internal.utils.subprocess import CommandArgs, call_subprocess, make_command
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from pip._internal.utils.urls import get_url_scheme
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__all__ = ['vcs']
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logger = logging.getLogger(__name__)
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AuthInfo = Tuple[Optional[str], Optional[str]]
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def is_url(name):
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# type: (str) -> bool
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"""
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Return true if the name looks like a URL.
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"""
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scheme = get_url_scheme(name)
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if scheme is None:
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return False
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return scheme in ['http', 'https', 'file', 'ftp'] + vcs.all_schemes
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def make_vcs_requirement_url(repo_url, rev, project_name, subdir=None):
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# type: (str, str, str, Optional[str]) -> str
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"""
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Return the URL for a VCS requirement.
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Args:
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repo_url: the remote VCS url, with any needed VCS prefix (e.g. "git+").
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project_name: the (unescaped) project name.
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"""
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egg_project_name = project_name.replace("-", "_")
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req = f'{repo_url}@{rev}#egg={egg_project_name}'
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if subdir:
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req += f'&subdirectory={subdir}'
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return req
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def find_path_to_project_root_from_repo_root(location, repo_root):
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# type: (str, str) -> Optional[str]
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"""
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Find the the Python project's root by searching up the filesystem from
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`location`. Return the path to project root relative to `repo_root`.
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Return None if the project root is `repo_root`, or cannot be found.
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"""
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# find project root.
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orig_location = location
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while not is_installable_dir(location):
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last_location = location
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location = os.path.dirname(location)
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if location == last_location:
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# We've traversed up to the root of the filesystem without
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# finding a Python project.
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logger.warning(
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"Could not find a Python project for directory %s (tried all "
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"parent directories)",
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orig_location,
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)
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return None
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if os.path.samefile(repo_root, location):
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return None
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return os.path.relpath(location, repo_root)
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class RemoteNotFoundError(Exception):
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pass
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class RemoteNotValidError(Exception):
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def __init__(self, url: str):
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super().__init__(url)
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self.url = url
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class RevOptions:
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"""
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Encapsulates a VCS-specific revision to install, along with any VCS
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install options.
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Instances of this class should be treated as if immutable.
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"""
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def __init__(
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self,
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vc_class, # type: Type[VersionControl]
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rev=None, # type: Optional[str]
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extra_args=None, # type: Optional[CommandArgs]
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):
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# type: (...) -> None
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"""
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Args:
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vc_class: a VersionControl subclass.
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rev: the name of the revision to install.
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extra_args: a list of extra options.
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"""
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if extra_args is None:
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extra_args = []
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self.extra_args = extra_args
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self.rev = rev
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self.vc_class = vc_class
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self.branch_name = None # type: Optional[str]
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def __repr__(self):
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# type: () -> str
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return f'<RevOptions {self.vc_class.name}: rev={self.rev!r}>'
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@property
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def arg_rev(self):
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# type: () -> Optional[str]
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if self.rev is None:
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return self.vc_class.default_arg_rev
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return self.rev
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def to_args(self):
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# type: () -> CommandArgs
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"""
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Return the VCS-specific command arguments.
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"""
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args = [] # type: CommandArgs
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rev = self.arg_rev
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if rev is not None:
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args += self.vc_class.get_base_rev_args(rev)
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args += self.extra_args
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return args
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def to_display(self):
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# type: () -> str
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if not self.rev:
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return ''
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return f' (to revision {self.rev})'
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def make_new(self, rev):
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# type: (str) -> RevOptions
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"""
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Make a copy of the current instance, but with a new rev.
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Args:
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rev: the name of the revision for the new object.
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"""
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return self.vc_class.make_rev_options(rev, extra_args=self.extra_args)
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class VcsSupport:
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_registry = {} # type: Dict[str, VersionControl]
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schemes = ['ssh', 'git', 'hg', 'bzr', 'sftp', 'svn']
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def __init__(self):
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# type: () -> None
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# Register more schemes with urlparse for various version control
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# systems
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urllib.parse.uses_netloc.extend(self.schemes)
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super().__init__()
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def __iter__(self):
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# type: () -> Iterator[str]
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return self._registry.__iter__()
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@property
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def backends(self):
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# type: () -> List[VersionControl]
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return list(self._registry.values())
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@property
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def dirnames(self):
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# type: () -> List[str]
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return [backend.dirname for backend in self.backends]
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@property
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def all_schemes(self):
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# type: () -> List[str]
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schemes = [] # type: List[str]
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for backend in self.backends:
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schemes.extend(backend.schemes)
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return schemes
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def register(self, cls):
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# type: (Type[VersionControl]) -> None
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if not hasattr(cls, 'name'):
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logger.warning('Cannot register VCS %s', cls.__name__)
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return
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if cls.name not in self._registry:
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self._registry[cls.name] = cls()
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logger.debug('Registered VCS backend: %s', cls.name)
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def unregister(self, name):
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# type: (str) -> None
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if name in self._registry:
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del self._registry[name]
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def get_backend_for_dir(self, location):
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# type: (str) -> Optional[VersionControl]
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"""
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Return a VersionControl object if a repository of that type is found
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at the given directory.
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"""
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vcs_backends = {}
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for vcs_backend in self._registry.values():
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repo_path = vcs_backend.get_repository_root(location)
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if not repo_path:
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continue
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logger.debug('Determine that %s uses VCS: %s',
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location, vcs_backend.name)
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vcs_backends[repo_path] = vcs_backend
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if not vcs_backends:
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return None
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# Choose the VCS in the inner-most directory. Since all repository
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# roots found here would be either `location` or one of its
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# parents, the longest path should have the most path components,
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# i.e. the backend representing the inner-most repository.
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inner_most_repo_path = max(vcs_backends, key=len)
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return vcs_backends[inner_most_repo_path]
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def get_backend_for_scheme(self, scheme):
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# type: (str) -> Optional[VersionControl]
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"""
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Return a VersionControl object or None.
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"""
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for vcs_backend in self._registry.values():
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if scheme in vcs_backend.schemes:
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return vcs_backend
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return None
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def get_backend(self, name):
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# type: (str) -> Optional[VersionControl]
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"""
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Return a VersionControl object or None.
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"""
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name = name.lower()
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return self._registry.get(name)
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vcs = VcsSupport()
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class VersionControl:
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name = ''
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dirname = ''
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repo_name = ''
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# List of supported schemes for this Version Control
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schemes = () # type: Tuple[str, ...]
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# Iterable of environment variable names to pass to call_subprocess().
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unset_environ = () # type: Tuple[str, ...]
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default_arg_rev = None # type: Optional[str]
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@classmethod
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def should_add_vcs_url_prefix(cls, remote_url):
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# type: (str) -> bool
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"""
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Return whether the vcs prefix (e.g. "git+") should be added to a
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repository's remote url when used in a requirement.
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"""
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return not remote_url.lower().startswith(f'{cls.name}:')
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@classmethod
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def get_subdirectory(cls, location):
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# type: (str) -> Optional[str]
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"""
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Return the path to Python project root, relative to the repo root.
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Return None if the project root is in the repo root.
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"""
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return None
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@classmethod
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def get_requirement_revision(cls, repo_dir):
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# type: (str) -> str
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"""
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Return the revision string that should be used in a requirement.
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"""
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return cls.get_revision(repo_dir)
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@classmethod
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def get_src_requirement(cls, repo_dir, project_name):
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# type: (str, str) -> str
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"""
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Return the requirement string to use to redownload the files
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currently at the given repository directory.
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Args:
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project_name: the (unescaped) project name.
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The return value has a form similar to the following:
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{repository_url}@{revision}#egg={project_name}
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"""
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repo_url = cls.get_remote_url(repo_dir)
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if cls.should_add_vcs_url_prefix(repo_url):
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repo_url = f'{cls.name}+{repo_url}'
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revision = cls.get_requirement_revision(repo_dir)
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subdir = cls.get_subdirectory(repo_dir)
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req = make_vcs_requirement_url(repo_url, revision, project_name,
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subdir=subdir)
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return req
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@staticmethod
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def get_base_rev_args(rev):
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# type: (str) -> List[str]
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"""
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Return the base revision arguments for a vcs command.
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Args:
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rev: the name of a revision to install. Cannot be None.
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"""
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raise NotImplementedError
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def is_immutable_rev_checkout(self, url, dest):
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# type: (str, str) -> bool
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"""
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Return true if the commit hash checked out at dest matches
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the revision in url.
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Always return False, if the VCS does not support immutable commit
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hashes.
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This method does not check if there are local uncommitted changes
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in dest after checkout, as pip currently has no use case for that.
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"""
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return False
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@classmethod
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def make_rev_options(cls, rev=None, extra_args=None):
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# type: (Optional[str], Optional[CommandArgs]) -> RevOptions
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"""
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Return a RevOptions object.
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Args:
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rev: the name of a revision to install.
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extra_args: a list of extra options.
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"""
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return RevOptions(cls, rev, extra_args=extra_args)
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@classmethod
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def _is_local_repository(cls, repo):
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# type: (str) -> bool
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"""
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posix absolute paths start with os.path.sep,
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win32 ones start with drive (like c:\\folder)
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"""
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drive, tail = os.path.splitdrive(repo)
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return repo.startswith(os.path.sep) or bool(drive)
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@classmethod
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def get_netloc_and_auth(cls, netloc, scheme):
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# type: (str, str) -> Tuple[str, Tuple[Optional[str], Optional[str]]]
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"""
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Parse the repository URL's netloc, and return the new netloc to use
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along with auth information.
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Args:
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netloc: the original repository URL netloc.
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scheme: the repository URL's scheme without the vcs prefix.
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This is mainly for the Subversion class to override, so that auth
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information can be provided via the --username and --password options
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instead of through the URL. For other subclasses like Git without
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such an option, auth information must stay in the URL.
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Returns: (netloc, (username, password)).
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"""
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return netloc, (None, None)
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@classmethod
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def get_url_rev_and_auth(cls, url):
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# type: (str) -> Tuple[str, Optional[str], AuthInfo]
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"""
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Parse the repository URL to use, and return the URL, revision,
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and auth info to use.
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Returns: (url, rev, (username, password)).
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"""
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scheme, netloc, path, query, frag = urllib.parse.urlsplit(url)
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if '+' not in scheme:
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raise ValueError(
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"Sorry, {!r} is a malformed VCS url. "
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"The format is <vcs>+<protocol>://<url>, "
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"e.g. svn+http://myrepo/svn/MyApp#egg=MyApp".format(url)
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)
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# Remove the vcs prefix.
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scheme = scheme.split('+', 1)[1]
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netloc, user_pass = cls.get_netloc_and_auth(netloc, scheme)
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rev = None
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if '@' in path:
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path, rev = path.rsplit('@', 1)
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if not rev:
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raise InstallationError(
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"The URL {!r} has an empty revision (after @) "
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"which is not supported. Include a revision after @ "
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"or remove @ from the URL.".format(url)
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)
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url = urllib.parse.urlunsplit((scheme, netloc, path, query, ''))
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return url, rev, user_pass
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@staticmethod
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def make_rev_args(username, password):
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# type: (Optional[str], Optional[HiddenText]) -> CommandArgs
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"""
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Return the RevOptions "extra arguments" to use in obtain().
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"""
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return []
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def get_url_rev_options(self, url):
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# type: (HiddenText) -> Tuple[HiddenText, RevOptions]
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"""
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Return the URL and RevOptions object to use in obtain(),
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as a tuple (url, rev_options).
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"""
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secret_url, rev, user_pass = self.get_url_rev_and_auth(url.secret)
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username, secret_password = user_pass
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password = None # type: Optional[HiddenText]
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if secret_password is not None:
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password = hide_value(secret_password)
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extra_args = self.make_rev_args(username, password)
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rev_options = self.make_rev_options(rev, extra_args=extra_args)
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return hide_url(secret_url), rev_options
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@staticmethod
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def normalize_url(url):
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# type: (str) -> str
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"""
|
|
Normalize a URL for comparison by unquoting it and removing any
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trailing slash.
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"""
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return urllib.parse.unquote(url).rstrip('/')
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|
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@classmethod
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def compare_urls(cls, url1, url2):
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# type: (str, str) -> bool
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"""
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|
Compare two repo URLs for identity, ignoring incidental differences.
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"""
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return (cls.normalize_url(url1) == cls.normalize_url(url2))
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def fetch_new(self, dest, url, rev_options):
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# type: (str, HiddenText, RevOptions) -> None
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"""
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Fetch a revision from a repository, in the case that this is the
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first fetch from the repository.
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Args:
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dest: the directory to fetch the repository to.
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rev_options: a RevOptions object.
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"""
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raise NotImplementedError
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def switch(self, dest, url, rev_options):
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# type: (str, HiddenText, RevOptions) -> None
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"""
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|
Switch the repo at ``dest`` to point to ``URL``.
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|
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|
Args:
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rev_options: a RevOptions object.
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"""
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raise NotImplementedError
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def update(self, dest, url, rev_options):
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# type: (str, HiddenText, RevOptions) -> None
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"""
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|
Update an already-existing repo to the given ``rev_options``.
|
|
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Args:
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rev_options: a RevOptions object.
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"""
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raise NotImplementedError
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|
|
|
@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.
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|
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|
Args:
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dest: the repository directory.
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name: a string name.
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"""
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raise NotImplementedError
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|
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def obtain(self, dest, url):
|
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# type: (str, HiddenText) -> None
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"""
|
|
Install or update in editable mode the package represented by this
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VersionControl object.
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:param dest: the repository directory in which to install or update.
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:param url: the repository URL starting with a vcs prefix.
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"""
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url, rev_options = self.get_url_rev_options(url)
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if not os.path.exists(dest):
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self.fetch_new(dest, url, rev_options)
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return
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rev_display = rev_options.to_display()
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if self.is_repository_directory(dest):
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existing_url = self.get_remote_url(dest)
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if self.compare_urls(existing_url, url.secret):
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logger.debug(
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'%s in %s exists, and has correct URL (%s)',
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self.repo_name.title(),
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display_path(dest),
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url,
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)
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if not self.is_commit_id_equal(dest, rev_options.rev):
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logger.info(
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'Updating %s %s%s',
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display_path(dest),
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self.repo_name,
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rev_display,
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)
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self.update(dest, url, rev_options)
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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? {}'.format(
|
|
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
|
|
stdout_only=False, # type: bool
|
|
):
|
|
# type: (...) -> str
|
|
"""
|
|
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,
|
|
stdout_only=stdout_only)
|
|
except FileNotFoundError:
|
|
# errno.ENOENT = no such file or directory
|
|
# In other words, the VCS executable isn't available
|
|
raise BadCommand(
|
|
f'Cannot find command {cls.name!r} - do you have '
|
|
f'{cls.name!r} installed and in your PATH?')
|
|
except PermissionError:
|
|
# errno.EACCES = Permission denied
|
|
# This error occurs, for instance, when the command is installed
|
|
# only for another user. So, the current user don't have
|
|
# permission to call the other user command.
|
|
raise BadCommand(
|
|
f"No permission to execute {cls.name!r} - install it "
|
|
f"locally, globally (ask admin), or check your PATH. "
|
|
f"See possible solutions at "
|
|
f"https://pip.pypa.io/en/latest/reference/pip_freeze/"
|
|
f"#fixing-permission-denied."
|
|
)
|
|
|
|
@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 get_repository_root(cls, location):
|
|
# type: (str) -> Optional[str]
|
|
"""
|
|
Return the "root" (top-level) directory controlled by the vcs,
|
|
or `None` if the directory is not in any.
|
|
|
|
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.
|
|
"""
|
|
if cls.is_repository_directory(location):
|
|
return location
|
|
return None
|