boltons.pathutils 源代码

# -*- coding: utf-8 -*-

# Copyright (c) 2013, Mahmoud Hashemi
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"""
Functions for working with filesystem paths.

The :func:`expandpath` function expands the tilde to $HOME and environment
variables to their values.

The :func:`augpath` function creates variants of an existing path without
having to spend multiple lines of code splitting it up and stitching it back
together.

The :func:`shrinkuser` function replaces your home directory with a tilde.
"""
from __future__ import print_function

from os.path import (expanduser, expandvars, join, normpath, split, splitext)
import os


__all__ = [
    'augpath', 'shrinkuser', 'expandpath',
]


[文档] def augpath(path, suffix='', prefix='', ext=None, base=None, dpath=None, multidot=False): """ Augment a path by modifying its components. Creates a new path with a different extension, basename, directory, prefix, and/or suffix. A prefix is inserted before the basename. A suffix is inserted between the basename and the extension. The basename and extension can be replaced with a new one. Essentially a path is broken down into components (dpath, base, ext), and then recombined as (dpath, prefix, base, suffix, ext) after replacing any specified component. Args: path (str | PathLike): a path to augment suffix (str, default=''): placed between the basename and extension prefix (str, default=''): placed in front of the basename ext (str, default=None): if specified, replaces the extension base (str, default=None): if specified, replaces the basename without extension dpath (str | PathLike, default=None): if specified, replaces the directory multidot (bool, default=False): Allows extensions to contain multiple dots. Specifically, if False, everything after the last dot in the basename is the extension. If True, everything after the first dot in the basename is the extension. Returns: str: augmented path Example: >>> path = 'foo.bar' >>> suffix = '_suff' >>> prefix = 'pref_' >>> ext = '.baz' >>> newpath = augpath(path, suffix, prefix, ext=ext, base='bar') >>> print('newpath = %s' % (newpath,)) newpath = pref_bar_suff.baz Example: >>> augpath('foo.bar') 'foo.bar' >>> augpath('foo.bar', ext='.BAZ') 'foo.BAZ' >>> augpath('foo.bar', suffix='_') 'foo_.bar' >>> augpath('foo.bar', prefix='_') '_foo.bar' >>> augpath('foo.bar', base='baz') 'baz.bar' >>> augpath('foo.tar.gz', ext='.zip', multidot=True) 'foo.zip' >>> augpath('foo.tar.gz', ext='.zip', multidot=False) 'foo.tar.zip' >>> augpath('foo.tar.gz', suffix='_new', multidot=True) 'foo_new.tar.gz' """ # Breakup path orig_dpath, fname = split(path) if multidot: # The first dot defines the extension parts = fname.split('.', 1) orig_base = parts[0] orig_ext = '' if len(parts) == 1 else '.' + parts[1] else: # The last dot defines the extension orig_base, orig_ext = splitext(fname) # Replace parts with specified augmentations if dpath is None: dpath = orig_dpath if ext is None: ext = orig_ext if base is None: base = orig_base # Recombine into new path new_fname = ''.join((prefix, base, suffix, ext)) newpath = join(dpath, new_fname) return newpath
[文档] def shrinkuser(path, home='~'): """ Inverse of :func:`os.path.expanduser`. Args: path (str | PathLike): path in system file structure home (str, default='~'): symbol used to replace the home path. Defaults to '~', but you might want to use '$HOME' or '%USERPROFILE%' instead. Returns: str: path: shortened path replacing the home directory with a tilde Example: >>> path = expanduser('~') >>> assert path != '~' >>> assert shrinkuser(path) == '~' >>> assert shrinkuser(path + '1') == path + '1' >>> assert shrinkuser(path + '/1') == join('~', '1') >>> assert shrinkuser(path + '/1', '$HOME') == join('$HOME', '1') """ path = normpath(path) userhome_dpath = expanduser('~') if path.startswith(userhome_dpath): if len(path) == len(userhome_dpath): path = home elif path[len(userhome_dpath)] == os.path.sep: path = home + path[len(userhome_dpath):] return path
[文档] def expandpath(path): """ Shell-like expansion of environment variables and tilde home directory. Args: path (str | PathLike): the path to expand Returns: str : expanded path Example: >>> import os >>> os.environ['SPAM'] = 'eggs' >>> assert expandpath('~/$SPAM') == expanduser('~/eggs') >>> assert expandpath('foo') == 'foo' """ path = expanduser(path) path = expandvars(path) return path