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""" path.py - An object representing a path to a file or directory. 

 

Example: 

 

from path import path 

d = path('/home/guido/bin') 

for f in d.files('*.py'): 

    f.chmod(0755) 

 

This module requires Python 2.2 or later. 

 

 

URL:     http://www.jorendorff.com/articles/python/path 

Author:  Jason Orendorff <jason@jorendorff.com> (and others - see the url!) 

Date:    29 Feb 2004 

""" 

 

 

# TODO 

#   - Bug in write_text().  It doesn't support Universal newline mode. 

#   - Better error message in listdir() when self isn't a 

#     directory. (On Windows, the error message really sucks.) 

#   - Make sure everything has a good docstring. 

#   - Add methods for regex find and replace. 

#   - guess_content_type() method? 

#   - Perhaps support arguments to touch(). 

#   - Could add split() and join() methods that generate warnings. 

#   - Note:  __add__() technically has a bug, I think, where 

#     it doesn't play nice with other types that implement 

#     __radd__().  Test this. 

 

from __future__ import generators 

 

import sys, os, fnmatch, glob, shutil, codecs 

 

__version__ = '2.0.2' 

__all__ = ['path'] 

 

# Pre-2.3 support.  Are unicode filenames supported? 

_base = str 

try: 

    if os.path.supports_unicode_filenames: 

        _base = unicode 

except AttributeError: 

    pass 

 

# Pre-2.3 workaround for basestring. 

try: 

    basestring 

except NameError: 

    basestring = (str, unicode) 

 

# Universal newline support 

_textmode = 'r' 

if hasattr(file, 'newlines'): 

    _textmode = 'U' 

 

 

class path(_base): 

    """ Represents a filesystem path. 

 

    For documentation on individual methods, consult their 

    counterparts in os.path. 

    """ 

 

    # --- Special Python methods. 

 

    def __repr__(self): 

        return 'path(%s)' % _base.__repr__(self) 

 

    # Adding a path and a string yields a path. 

    def __add__(self, more): 

        return path(_base(self) + more) 

 

    def __radd__(self, other): 

        return path(other + _base(self)) 

 

    # The / operator joins paths. 

    def __div__(self, rel): 

        """ fp.__div__(rel) == fp / rel == fp.joinpath(rel) 

 

        Join two path components, adding a separator character if 

        needed. 

        """ 

        return path(os.path.join(self, rel)) 

 

    # Make the / operator work even when true division is enabled. 

    __truediv__ = __div__ 

 

    def getcwd(): 

        """ Return the current working directory as a path object. """ 

        return path(os.getcwd()) 

    getcwd = staticmethod(getcwd) 

 

 

    # --- Operations on path strings. 

 

    def abspath(self):       return path(os.path.abspath(self)) 

    def normcase(self):      return path(os.path.normcase(self)) 

    def normpath(self):      return path(os.path.normpath(self)) 

    def realpath(self):      return path(os.path.realpath(self)) 

    def expanduser(self):    return path(os.path.expanduser(self)) 

    def expandvars(self):    return path(os.path.expandvars(self)) 

    def dirname(self):       return path(os.path.dirname(self)) 

    basename = os.path.basename 

 

    def expand(self): 

        """ Clean up a filename by calling expandvars(), 

        expanduser(), and normpath() on it. 

 

        This is commonly everything needed to clean up a filename 

        read from a configuration file, for example. 

        """ 

        return self.expandvars().expanduser().normpath() 

 

    def _get_namebase(self): 

        base, ext = os.path.splitext(self.name) 

        return base 

 

    def _get_ext(self): 

        f, ext = os.path.splitext(_base(self)) 

        return ext 

 

    def _get_drive(self): 

        drive, r = os.path.splitdrive(self) 

        return path(drive) 

 

    parent = property( 

        dirname, None, None, 

        """ This path's parent directory, as a new path object. 

 

        For example, path('/usr/local/lib/libpython.so').parent == path('/usr/local/lib') 

        """) 

 

    name = property( 

        basename, None, None, 

        """ The name of this file or directory without the full path. 

 

        For example, path('/usr/local/lib/libpython.so').name == 'libpython.so' 

        """) 

 

    namebase = property( 

        _get_namebase, None, None, 

        """ The same as path.name, but with one file extension stripped off. 

 

        For example, path('/home/guido/python.tar.gz').name     == 'python.tar.gz', 

        but          path('/home/guido/python.tar.gz').namebase == 'python.tar' 

        """) 

 

    ext = property( 

        _get_ext, None, None, 

        """ The file extension, for example '.py'. """) 

 

    drive = property( 

        _get_drive, None, None, 

        """ The drive specifier, for example 'C:'. 

        This is always empty on systems that don't use drive specifiers. 

        """) 

 

    def splitpath(self): 

        """ p.splitpath() -> Return (p.parent, p.name). """ 

        parent, child = os.path.split(self) 

        return path(parent), child 

 

    def splitdrive(self): 

        """ p.splitdrive() -> Return (p.drive, <the rest of p>). 

 

        Split the drive specifier from this path.  If there is 

        no drive specifier, p.drive is empty, so the return value 

        is simply (path(''), p).  This is always the case on Unix. 

        """ 

        drive, rel = os.path.splitdrive(self) 

        return path(drive), rel 

 

    def splitext(self): 

        """ p.splitext() -> Return (p.stripext(), p.ext). 

 

        Split the filename extension from this path and return 

        the two parts.  Either part may be empty. 

 

        The extension is everything from '.' to the end of the 

        last path segment.  This has the property that if 

        (a, b) == p.splitext(), then a + b == p. 

        """ 

        # Cast to plain string using _base because Python 2.2 

        # implementations of os.path.splitext use "for c in path:..." 

        # which means something different when applied to a path 

        # object. 

        filename, ext = os.path.splitext(_base(self)) 

        return path(filename), ext 

 

    def stripext(self): 

        """ p.stripext() -> Remove one file extension from the path. 

 

        For example, path('/home/guido/python.tar.gz').stripext() 

        returns path('/home/guido/python.tar'). 

        """ 

        return self.splitext()[0] 

 

    if hasattr(os.path, 'splitunc'): 

        def splitunc(self): 

            unc, rest = os.path.splitunc(self) 

            return path(unc), rest 

 

        def _get_uncshare(self): 

            unc, r = os.path.splitunc(self) 

            return path(unc) 

 

        uncshare = property( 

            _get_uncshare, None, None, 

            """ The UNC mount point for this path. 

            This is empty for paths on local drives. """) 

 

    def joinpath(self, *args): 

        """ Join two or more path components, adding a separator 

        character (os.sep) if needed.  Returns a new path 

        object. 

        """ 

        return path(os.path.join(self, *args)) 

 

    def splitall(self): 

        """ Return a list of the path components in this path. 

 

        The first item in the list will be a path.  Its value will be 

        either os.curdir, os.pardir, empty, or the root directory of 

        this path (for example, '/' or 'C:\\').  The other items in 

        the list will be strings. 

 

        path.path.joinpath(*result) will yield the original path. 

        """ 

        parts = [] 

        loc = self 

        while loc != os.curdir and loc != os.pardir: 

            prev = loc 

            loc, child = prev.splitpath() 

            if loc == prev: 

                break 

            parts.append(child) 

        parts.append(loc) 

        parts.reverse() 

        return parts 

 

    def relpath(self): 

        """ Return this path as a relative path, 

        based from the current working directory. 

        """ 

        cwd = path(os.getcwd()) 

        return cwd.relpathto(self) 

 

    def relpathto(self, dest): 

        """ Return a relative path from self to dest. 

 

        If there is no relative path from self to dest, for example if 

        they reside on different drives in Windows, then this returns 

        dest.abspath(). 

        """ 

        origin = self.abspath() 

        dest = path(dest).abspath() 

 

        orig_list = origin.normcase().splitall() 

        # Don't normcase dest!  We want to preserve the case. 

        dest_list = dest.splitall() 

 

        if orig_list[0] != os.path.normcase(dest_list[0]): 

            # Can't get here from there. 

            return dest 

 

        # Find the location where the two paths start to differ. 

        i = 0 

        for start_seg, dest_seg in zip(orig_list, dest_list): 

            if start_seg != os.path.normcase(dest_seg): 

                break 

            i += 1 

 

        # Now i is the point where the two paths diverge. 

        # Need a certain number of "os.pardir"s to work up 

        # from the origin to the point of divergence. 

        segments = [os.pardir] * (len(orig_list) - i) 

        # Need to add the diverging part of dest_list. 

        segments += dest_list[i:] 

        if len(segments) == 0: 

            # If they happen to be identical, use os.curdir. 

            return path(os.curdir) 

        else: 

            return path(os.path.join(*segments)) 

 

 

    # --- Listing, searching, walking, and matching 

 

    def listdir(self, pattern=None): 

        """ D.listdir() -> List of items in this directory. 

 

        Use D.files() or D.dirs() instead if you want a listing 

        of just files or just subdirectories. 

 

        The elements of the list are path objects. 

 

        With the optional 'pattern' argument, this only lists 

        items whose names match the given pattern. 

        """ 

        names = os.listdir(self) 

        if pattern is not None: 

            names = fnmatch.filter(names, pattern) 

        return [self / child for child in names] 

 

    def dirs(self, pattern=None): 

        """ D.dirs() -> List of this directory's subdirectories. 

 

        The elements of the list are path objects. 

        This does not walk recursively into subdirectories 

        (but see path.walkdirs). 

 

        With the optional 'pattern' argument, this only lists 

        directories whose names match the given pattern.  For 

        example, d.dirs('build-*'). 

        """ 

        return [p for p in self.listdir(pattern) if p.isdir()] 

 

    def files(self, pattern=None): 

        """ D.files() -> List of the files in this directory. 

 

        The elements of the list are path objects. 

        This does not walk into subdirectories (see path.walkfiles). 

 

        With the optional 'pattern' argument, this only lists files 

        whose names match the given pattern.  For example, 

        d.files('*.pyc'). 

        """ 

 

        return [p for p in self.listdir(pattern) if p.isfile()] 

 

    def walk(self, pattern=None): 

        """ D.walk() -> iterator over files and subdirs, recursively. 

 

        The iterator yields path objects naming each child item of 

        this directory and its descendants.  This requires that 

        D.isdir(). 

 

        This performs a depth-first traversal of the directory tree. 

        Each directory is returned just before all its children. 

        """ 

        for child in self.listdir(): 

            if pattern is None or child.fnmatch(pattern): 

                yield child 

            if child.isdir(): 

                for item in child.walk(pattern): 

                    yield item 

 

    def walkdirs(self, pattern=None): 

        """ D.walkdirs() -> iterator over subdirs, recursively. 

 

        With the optional 'pattern' argument, this yields only 

        directories whose names match the given pattern.  For 

        example, mydir.walkdirs('*test') yields only directories 

        with names ending in 'test'. 

        """ 

        for child in self.dirs(): 

            if pattern is None or child.fnmatch(pattern): 

                yield child 

            for subsubdir in child.walkdirs(pattern): 

                yield subsubdir 

 

    def walkfiles(self, pattern=None): 

        """ D.walkfiles() -> iterator over files in D, recursively. 

 

        The optional argument, pattern, limits the results to files 

        with names that match the pattern.  For example, 

        mydir.walkfiles('*.tmp') yields only files with the .tmp 

        extension. 

        """ 

        for child in self.listdir(): 

            if child.isfile(): 

                if pattern is None or child.fnmatch(pattern): 

                    yield child 

            elif child.isdir(): 

                for f in child.walkfiles(pattern): 

                    yield f 

 

    def fnmatch(self, pattern): 

        """ Return True if self.name matches the given pattern. 

 

        pattern - A filename pattern with wildcards, 

            for example '*.py'. 

        """ 

        return fnmatch.fnmatch(self.name, pattern) 

 

    def glob(self, pattern): 

        """ Return a list of path objects that match the pattern. 

 

        pattern - a path relative to this directory, with wildcards. 

 

        For example, path('/users').glob('*/bin/*') returns a list 

        of all the files users have in their bin directories. 

        """ 

        return map(path, glob.glob(_base(self / pattern))) 

 

 

    # --- Reading or writing an entire file at once. 

 

    def open(self, mode='r'): 

        """ Open this file.  Return a file object. """ 

        return file(self, mode) 

 

    def bytes(self): 

        """ Open this file, read all bytes, return them as a string. """ 

        f = self.open('rb') 

        try: 

            return f.read() 

        finally: 

            f.close() 

 

    def write_bytes(self, bytes, append=False): 

        """ Open this file and write the given bytes to it. 

 

        Default behavior is to overwrite any existing file. 

        Call this with write_bytes(bytes, append=True) to append instead. 

        """ 

        if append: 

            mode = 'ab' 

        else: 

            mode = 'wb' 

        f = self.open(mode) 

        try: 

            f.write(bytes) 

        finally: 

            f.close() 

 

    def text(self, encoding=None, errors='strict'): 

        """ Open this file, read it in, return the content as a string. 

 

        This uses 'U' mode in Python 2.3 and later, so '\r\n' and '\r' 

        are automatically translated to '\n'. 

 

        Optional arguments: 

 

        encoding - The Unicode encoding (or character set) of 

            the file.  If present, the content of the file is 

            decoded and returned as a unicode object; otherwise 

            it is returned as an 8-bit str. 

        errors - How to handle Unicode errors; see help(str.decode) 

            for the options.  Default is 'strict'. 

        """ 

        if encoding is None: 

            # 8-bit 

            f = self.open(_textmode) 

            try: 

                return f.read() 

            finally: 

                f.close() 

        else: 

            # Unicode 

            f = codecs.open(self, 'r', encoding, errors) 

            # (Note - Can't use 'U' mode here, since codecs.open 

            # doesn't support 'U' mode, even in Python 2.3.) 

            try: 

                t = f.read() 

            finally: 

                f.close() 

            return t.replace(u'\r\n', u'\n').replace(u'\r', u'\n') 

 

    def write_text(self, text, encoding=None, errors='strict', append=False): 

        """ Write the given text to this file. 

 

        The default behavior is to overwrite any existing file; 

        to append instead, use the 'append=True' keyword argument. 

 

        There are two differences between path.write_text() and 

        path.write_bytes(): Unicode handling and newline handling. 

 

        --- Unicode 

 

        If 'text' isn't Unicode, this essentially just does 

        open(self, 'w').write(text).  The 'encoding' and 'errors' 

        arguments are ignored. 

 

        If 'text' is Unicode, it is first converted to bytes using the 

        specified 'encoding' (or the default encoding if 'encoding' 

        isn't specified).  The 'errors' argument applies only to this 

        conversion. 

 

        --- Newlines 

 

        write_text() converts from programmer-friendly newlines 

        (always '\n') to platform-specific newlines (see os.linesep; 

        on Windows, for example, the end-of-line marker is '\r\n'). 

        This applies to Unicode text the same as to 8-bit text. 

 

        Because of this conversion, the text should only contain plain 

        newlines ('\n'), just like the return value of path.text(). 

        If the text contains the characters '\r\n', it may be written 

        as '\r\r\n' or '\r\r' depending on your platform.  (This is 

        exactly the same as when you open a file for writing with 

        fopen(filename, "w") in C or file(filename, 'w') in Python.) 

        """ 

        if isinstance(text, unicode): 

            text = text.replace(u'\n', os.linesep) 

            if encoding is None: 

                encoding = sys.getdefaultencoding() 

            bytes = text.encode(encoding, errors) 

            self.write_bytes(bytes, append) 

        else: 

            if append: 

                mode = 'a' 

            else: 

                mode = 'w' 

            f = self.open(mode) 

            try: 

                f.write(text) 

            finally: 

                f.close() 

 

    def lines(self, encoding=None, errors='strict', retain=True): 

        """ Open this file, read all lines, return them in a list. 

 

        Optional arguments: 

            encoding - The Unicode encoding (or character set) of 

                the file.  The default is None, meaning the content 

                of the file is read as 8-bit characters and returned 

                as a list of (non-Unicode) str objects. 

            errors - How to handle Unicode errors; see help(str.decode) 

                for the options.  Default is 'strict' 

            retain - If true, retain newline characters; but all newline 

                character combinations ('\r', '\n', '\r\n') are 

                translated to '\n'.  If false, newline characters are 

                stripped off.  Default is True. 

 

        This uses 'U' mode in Python 2.3 and later. 

        """ 

        if encoding is None and retain: 

            f = self.open(_textmode) 

            try: 

                return f.readlines() 

            finally: 

                f.close() 

        else: 

            return self.text(encoding, errors).splitlines(retain) 

 

    def write_lines(self, lines, encoding=None, errors='strict', 

                    linesep=os.linesep): 

        """ Overwrite this file with the given lines of text. 

 

        lines - A list of strings. 

        encoding - A Unicode encoding to use.  This applies only if 

            'lines' contains any Unicode strings. 

        errors - How to handle errors in Unicode encoding.  This 

            also applies only to Unicode strings. 

        linesep - A character sequence that will be added at the 

            end of every line that doesn't already have it. 

        """ 

        f = self.open('wb') 

        try: 

            for line in lines: 

                if not line.endswith(linesep): 

                    line += linesep 

                if isinstance(line, unicode): 

                    if encoding is None: 

                        encoding = sys.getdefaultencoding() 

                    line = line.encode(encoding, errors=errors) 

                f.write(line) 

        finally: 

            f.close() 

 

 

    # --- Methods for querying the filesystem. 

 

    exists = os.path.exists 

    isabs = os.path.isabs 

    isdir = os.path.isdir 

    isfile = os.path.isfile 

    islink = os.path.islink 

    ismount = os.path.ismount 

 

    if hasattr(os.path, 'samefile'): 

        samefile = os.path.samefile 

 

    getatime = os.path.getatime 

    atime = property( 

        getatime, None, None, 

        """ Last access time of the file. """) 

 

    getmtime = os.path.getmtime 

    mtime = property( 

        getmtime, None, None, 

        """ Last-modified time of the file. """) 

 

    if hasattr(os.path, 'getctime'): 

        getctime = os.path.getctime 

        ctime = property( 

            getctime, None, None, 

            """ Creation time of the file. """) 

 

    getsize = os.path.getsize 

    size = property( 

        getsize, None, None, 

        """ Size of the file, in bytes. """) 

 

    if hasattr(os, 'access'): 

        def access(self, mode): 

            """ Return true if current user has access to this path. 

 

            mode - One of the constants os.F_OK, os.R_OK, os.W_OK, os.X_OK 

            """ 

            return os.access(self, mode) 

 

    def stat(self): 

        """ Perform a stat() system call on this path. """ 

        return os.stat(self) 

 

    def lstat(self): 

        """ Like path.stat(), but do not follow symbolic links. """ 

        return os.lstat(self) 

 

    if hasattr(os, 'statvfs'): 

        def statvfs(self): 

            """ Perform a statvfs() system call on this path. """ 

            return os.statvfs(self) 

 

    if hasattr(os, 'pathconf'): 

        def pathconf(self, name): 

            return os.pathconf(self, name) 

 

 

    # --- Modifying operations on files and directories 

 

    def utime(self, times): 

        """ Set the access and modified times of this file. """ 

        os.utime(self, times) 

 

    def chmod(self, mode): 

        os.chmod(self, mode) 

 

    if hasattr(os, 'chown'): 

        def chown(self, uid, gid): 

            os.chown(self, uid, gid) 

 

    def rename(self, new): 

        os.rename(self, new) 

 

    def renames(self, new): 

        os.renames(self, new) 

 

 

    # --- Create/delete operations on directories 

 

    def mkdir(self, mode=0777): 

        os.mkdir(self, mode) 

 

    def makedirs(self, mode=0777): 

        os.makedirs(self, mode) 

 

    def rmdir(self): 

        os.rmdir(self) 

 

    def removedirs(self): 

        os.removedirs(self) 

 

 

    # --- Modifying operations on files 

 

    def touch(self): 

        """ Set the access/modified times of this file to the current time. 

        Create the file if it does not exist. 

        """ 

        fd = os.open(self, os.O_WRONLY | os.O_CREAT, 0666) 

        os.close(fd) 

        os.utime(self, None) 

 

    def remove(self): 

        os.remove(self) 

 

    def unlink(self): 

        os.unlink(self) 

 

 

    # --- Links 

 

    if hasattr(os, 'link'): 

        def link(self, newpath): 

            """ Create a hard link at 'newpath', pointing to this file. """ 

            os.link(self, newpath) 

 

    if hasattr(os, 'symlink'): 

        def symlink(self, newlink): 

            """ Create a symbolic link at 'newlink', pointing here. """ 

            os.symlink(self, newlink) 

 

    if hasattr(os, 'readlink'): 

        def readlink(self): 

            """ Return the path to which this symbolic link points. 

 

            The result may be an absolute or a relative path. 

            """ 

            return path(os.readlink(self)) 

 

        def readlinkabs(self): 

            """ Return the path to which this symbolic link points. 

 

            The result is always an absolute path. 

            """ 

            p = self.readlink() 

            if p.isabs(): 

                return p 

            else: 

                return (self.parent / p).abspath() 

 

 

    # --- High-level functions from shutil 

 

    copyfile = shutil.copyfile 

    copymode = shutil.copymode 

    copystat = shutil.copystat 

    copy = shutil.copy 

    copy2 = shutil.copy2 

    copytree = shutil.copytree 

    if hasattr(shutil, 'move'): 

        move = shutil.move 

    rmtree = shutil.rmtree 

 

 

    # --- Special stuff from os 

 

    if hasattr(os, 'chroot'): 

        def chroot(self): 

            os.chroot(self) 

 

    if hasattr(os, 'startfile'): 

        def startfile(self): 

            os.startfile(self)