1import os 2import sys 3 4try: 5 from functools import wraps 6except ImportError: 7 # only needed for Python 2.4 8 def wraps(_): 9 def _wraps(func): 10 return func 11 return _wraps 12 13__unittest = True 14 15def _relpath_nt(path, start=os.path.curdir): 16 """Return a relative version of a path""" 17 18 if not path: 19 raise ValueError("no path specified") 20 start_list = os.path.abspath(start).split(os.path.sep) 21 path_list = os.path.abspath(path).split(os.path.sep) 22 if start_list[0].lower() != path_list[0].lower(): 23 unc_path, rest = os.path.splitunc(path) 24 unc_start, rest = os.path.splitunc(start) 25 if bool(unc_path) ^ bool(unc_start): 26 raise ValueError("Cannot mix UNC and non-UNC paths (%s and %s)" 27 % (path, start)) 28 else: 29 raise ValueError("path is on drive %s, start on drive %s" 30 % (path_list[0], start_list[0])) 31 # Work out how much of the filepath is shared by start and path. 32 for i in range(min(len(start_list), len(path_list))): 33 if start_list[i].lower() != path_list[i].lower(): 34 break 35 else: 36 i += 1 37 38 rel_list = [os.path.pardir] * (len(start_list)-i) + path_list[i:] 39 if not rel_list: 40 return os.path.curdir 41 return os.path.join(*rel_list) 42 43# default to posixpath definition 44def _relpath_posix(path, start=os.path.curdir): 45 """Return a relative version of a path""" 46 47 if not path: 48 raise ValueError("no path specified") 49 50 start_list = os.path.abspath(start).split(os.path.sep) 51 path_list = os.path.abspath(path).split(os.path.sep) 52 53 # Work out how much of the filepath is shared by start and path. 54 i = len(os.path.commonprefix([start_list, path_list])) 55 56 rel_list = [os.path.pardir] * (len(start_list)-i) + path_list[i:] 57 if not rel_list: 58 return os.path.curdir 59 return os.path.join(*rel_list) 60 61if os.path is sys.modules.get('ntpath'): 62 relpath = _relpath_nt 63else: 64 relpath = _relpath_posix 65