JezK
Edit File: genericpath.py
""" Path operations common to more than one OS Do not use directly. The OS specific modules import the appropriate functions from this module themselves. """ import os import stat __all__ = ['commonprefix', 'exists', 'getatime', 'getctime', 'getmtime', 'getsize', 'isdir', 'isfile', 'samefile', 'sameopenfile', 'samestat'] # Does a path exist? # This is false for dangling symbolic links on systems that support them. def exists(path): """Test whether a path exists. Returns False for broken symbolic links""" try: os.stat(path) except (OSError, ValueError): return False return True # This follows symbolic links, so both islink() and isdir() can be true # for the same path on systems that support symlinks def isfile(path): """Test whether a path is a regular file""" try: st = os.stat(path) except (OSError, ValueError): return False return stat.S_ISREG(st.st_mode) # Is a path a directory? # This follows symbolic links, so both islink() and isdir() # can be true for the same path on systems that support symlinks def isdir(s): """Return true if the pathname refers to an existing directory.""" try: st = os.stat(s) except (OSError, ValueError): return False return stat.S_ISDIR(st.st_mode) def getsize(filename): """Return the size of a file, reported by os.stat().""" return os.stat(filename).st_size def getmtime(filename): """Return the last modification time of a file, reported by os.stat().""" return os.stat(filename).st_mtime def getatime(filename): """Return the last access time of a file, reported by os.stat().""" return os.stat(filename).st_atime def getctime(filename): """Return the metadata change time of a file, reported by os.stat().""" return os.stat(filename).st_ctime # Return the longest prefix of all list elements. def commonprefix(m): "Given a list of pathnames, returns the longest common leading component" if not m: return '' # Some people pass in a list of pathname parts to operate in an OS-agnostic # fashion; don't try to translate in that case as that's an abuse of the # API and they are already doing what they need to be OS-agnostic and so # they most likely won't be using an os.PathLike object in the sublists. if not isinstance(m[0], (list, tuple)): m = tuple(map(os.fspath, m)) s1 = min(m) s2 = max(m) for i, c in enumerate(s1): if c != s2[i]: return s1[:i] return s1 # Are two stat buffers (obtained from stat, fstat or lstat) # describing the same file? def samestat(s1, s2): """Test whether two stat buffers reference the same file""" return (s1.st_ino == s2.st_ino and s1.st_dev == s2.st_dev) # Are two filenames really pointing to the same file? def samefile(f1, f2): """Test whether two pathnames reference the same actual file or directory This is determined by the device number and i-node number and raises an exception if an os.stat() call on either pathname fails. """ s1 = os.stat(f1) s2 = os.stat(f2) return samestat(s1, s2) # Are two open files really referencing the same file? # (Not necessarily the same file descriptor!) def sameopenfile(fp1, fp2): """Test whether two open file objects reference the same file""" s1 = os.fstat(fp1) s2 = os.fstat(fp2) return samestat(s1, s2) # Split a path in root and extension. # The extension is everything starting at the last dot in the last # pathname component; the root is everything before that. # It is always true that root + ext == p. # Generic implementation of splitext, to be parametrized with # the separators def _splitext(p, sep, altsep, extsep): """Split the extension from a pathname. Extension is everything from the last dot to the end, ignoring leading dots. Returns "(root, ext)"; ext may be empty.""" # NOTE: This code must work for text and bytes strings. sepIndex = p.rfind(sep) if altsep: altsepIndex = p.rfind(altsep) sepIndex = max(sepIndex, altsepIndex) dotIndex = p.rfind(extsep) if dotIndex > sepIndex: # skip all leading dots filenameIndex = sepIndex + 1 while filenameIndex < dotIndex: if p[filenameIndex:filenameIndex+1] != extsep: return p[:dotIndex], p[dotIndex:] filenameIndex += 1 return p, p[:0] def _check_arg_types(funcname, *args): hasstr = hasbytes = False for s in args: if isinstance(s, str): hasstr = True elif isinstance(s, bytes): hasbytes = True else: raise TypeError(f'{funcname}() argument must be str, bytes, or ' f'os.PathLike object, not {s.__class__.__name__!r}') from None if hasstr and hasbytes: raise TypeError("Can't mix strings and bytes in path components") from None