IPython/utils/path.py: Sometimes this system encoding just won't work. So, we try to use it if we can, but fallback to UTF8 if it simply won't work.

IPython/utils/path.py

@@ -1,454 +1,458 b''
 # encoding: utf-8
 """
 Utilities for path handling.
 """
 
 # Copyright (c) IPython Development Team.
 # Distributed under the terms of the Modified BSD License.
 
 import os
 import sys
 import errno
 import shutil
 import random
 import tempfile
 import glob
 from warnings import warn
 from hashlib import md5
 
 from IPython.utils.process import system
 from IPython.utils import py3compat
 from IPython.utils.decorators import undoc
 
 #-----------------------------------------------------------------------------
 # Code
 #-----------------------------------------------------------------------------
 
 fs_encoding = sys.getfilesystemencoding()
 
 def _writable_dir(path):
     """Whether `path` is a directory, to which the user has write access."""
     return os.path.isdir(path) and os.access(path, os.W_OK)
 
 if sys.platform == 'win32':
     def _get_long_path_name(path):
         """Get a long path name (expand ~) on Windows using ctypes.
 
         Examples
         --------
 
         >>> get_long_path_name('c:\\docume~1')
         u'c:\\\\Documents and Settings'
 
         """
         try:
             import ctypes
         except ImportError:
             raise ImportError('you need to have ctypes installed for this to work')
         _GetLongPathName = ctypes.windll.kernel32.GetLongPathNameW
         _GetLongPathName.argtypes = [ctypes.c_wchar_p, ctypes.c_wchar_p,
             ctypes.c_uint ]
 
         buf = ctypes.create_unicode_buffer(260)
         rv = _GetLongPathName(path, buf, 260)
         if rv == 0 or rv > 260:
             return path
         else:
             return buf.value
 else:
     def _get_long_path_name(path):
         """Dummy no-op."""
         return path
 
 
 
 def get_long_path_name(path):
     """Expand a path into its long form.
 
     On Windows this expands any ~ in the paths. On other platforms, it is
     a null operation.
     """
     return _get_long_path_name(path)
 
 
 def unquote_filename(name, win32=(sys.platform=='win32')):
     """ On Windows, remove leading and trailing quotes from filenames.
     """
     if win32:
         if name.startswith(("'", '"')) and name.endswith(("'", '"')):
             name = name[1:-1]
     return name
 
 def compress_user(path):
     """Reverse of :func:`os.path.expanduser`
     """    
     path = py3compat.unicode_to_str(path, sys.getfilesystemencoding())
     home = os.path.expanduser('~')
     if path.startswith(home):
         path =  "~" + path[len(home):]
     return path
 
 def get_py_filename(name, force_win32=None):
     """Return a valid python filename in the current directory.
 
     If the given name is not a file, it adds '.py' and searches again.
     Raises IOError with an informative message if the file isn't found.
 
     On Windows, apply Windows semantics to the filename. In particular, remove
     any quoting that has been applied to it. This option can be forced for
     testing purposes.
     """
 
     name = os.path.expanduser(name)
     if force_win32 is None:
         win32 = (sys.platform == 'win32')
     else:
         win32 = force_win32
     name = unquote_filename(name, win32=win32)
     if not os.path.isfile(name) and not name.endswith('.py'):
         name += '.py'
     if os.path.isfile(name):
         return name
     else:
         raise IOError('File `%r` not found.' % name)
 
 
 def filefind(filename, path_dirs=None):
     """Find a file by looking through a sequence of paths.
 
     This iterates through a sequence of paths looking for a file and returns
     the full, absolute path of the first occurence of the file.  If no set of
     path dirs is given, the filename is tested as is, after running through
     :func:`expandvars` and :func:`expanduser`.  Thus a simple call::
 
         filefind('myfile.txt')
 
     will find the file in the current working dir, but::
 
         filefind('~/myfile.txt')
 
     Will find the file in the users home directory.  This function does not
     automatically try any paths, such as the cwd or the user's home directory.
 
     Parameters
     ----------
     filename : str
         The filename to look for.
     path_dirs : str, None or sequence of str
         The sequence of paths to look for the file in.  If None, the filename
         need to be absolute or be in the cwd.  If a string, the string is
         put into a sequence and the searched.  If a sequence, walk through
         each element and join with ``filename``, calling :func:`expandvars`
         and :func:`expanduser` before testing for existence.
 
     Returns
     -------
     Raises :exc:`IOError` or returns absolute path to file.
     """
 
     # If paths are quoted, abspath gets confused, strip them...
     filename = filename.strip('"').strip("'")
     # If the input is an absolute path, just check it exists
     if os.path.isabs(filename) and os.path.isfile(filename):
         return filename
 
     if path_dirs is None:
         path_dirs = ("",)
     elif isinstance(path_dirs, py3compat.string_types):
         path_dirs = (path_dirs,)
 
     for path in path_dirs:
         if path == '.': path = py3compat.getcwd()
         testname = expand_path(os.path.join(path, filename))
         if os.path.isfile(testname):
             return os.path.abspath(testname)
 
     raise IOError("File %r does not exist in any of the search paths: %r" %
                   (filename, path_dirs) )
 
 
 class HomeDirError(Exception):
     pass
 
 
 def get_home_dir(require_writable=False):
     """Return the 'home' directory, as a unicode string.
 
     Uses os.path.expanduser('~'), and checks for writability.
 
     See stdlib docs for how this is determined.
     $HOME is first priority on *ALL* platforms.
 
     Parameters
     ----------
 
     require_writable : bool [default: False]
         if True:
             guarantees the return value is a writable directory, otherwise
             raises HomeDirError
         if False:
             The path is resolved, but it is not guaranteed to exist or be writable.
     """
 
     homedir = os.path.expanduser('~')
     # Next line will make things work even when /home/ is a symlink to
     # /usr/home as it is on FreeBSD, for example
     homedir = os.path.realpath(homedir)
 
     if not _writable_dir(homedir) and os.name == 'nt':
         # expanduser failed, use the registry to get the 'My Documents' folder.
         try:
             try:
                 import winreg as wreg  # Py 3
             except ImportError:
                 import _winreg as wreg  # Py 2
             key = wreg.OpenKey(
                 wreg.HKEY_CURRENT_USER,
                 "Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders"
             )
             homedir = wreg.QueryValueEx(key,'Personal')[0]
             key.Close()
         except:
             pass
 
     if (not require_writable) or _writable_dir(homedir):
         return py3compat.cast_unicode(homedir, fs_encoding)
     else:
         raise HomeDirError('%s is not a writable dir, '
                 'set $HOME environment variable to override' % homedir)
 
 def get_xdg_dir():
     """Return the XDG_CONFIG_HOME, if it is defined and exists, else None.
 
     This is only for non-OS X posix (Linux,Unix,etc.) systems.
     """
 
     env = os.environ
 
     if os.name == 'posix' and sys.platform != 'darwin':
         # Linux, Unix, AIX, etc.
         # use ~/.config if empty OR not set
         xdg = env.get("XDG_CONFIG_HOME", None) or os.path.join(get_home_dir(), '.config')
         if xdg and _writable_dir(xdg):
             return py3compat.cast_unicode(xdg, fs_encoding)
 
     return None
 
 
 def get_xdg_cache_dir():
     """Return the XDG_CACHE_HOME, if it is defined and exists, else None.
 
     This is only for non-OS X posix (Linux,Unix,etc.) systems.
     """
 
     env = os.environ
 
     if os.name == 'posix' and sys.platform != 'darwin':
         # Linux, Unix, AIX, etc.
         # use ~/.cache if empty OR not set
         xdg = env.get("XDG_CACHE_HOME", None) or os.path.join(get_home_dir(), '.cache')
         if xdg and _writable_dir(xdg):
             return py3compat.cast_unicode(xdg, fs_encoding)
 
     return None
 
 
 @undoc
 def get_ipython_dir():
     warn("get_ipython_dir has moved to the IPython.paths module")
     from IPython.paths import get_ipython_dir
     return get_ipython_dir()
 
 @undoc
 def get_ipython_cache_dir():
     warn("get_ipython_cache_dir has moved to the IPython.paths module")
     from IPython.paths import get_ipython_cache_dir
     return get_ipython_cache_dir()
 
 @undoc
 def get_ipython_package_dir():
     warn("get_ipython_package_dir has moved to the IPython.paths module")
     from IPython.paths import get_ipython_package_dir
     return get_ipython_package_dir()
 
 @undoc
 def get_ipython_module_path(module_str):
     warn("get_ipython_module_path has moved to the IPython.paths module")
     from IPython.paths import get_ipython_module_path
     return get_ipython_module_path(module_str)
 
 @undoc
 def locate_profile(profile='default'):
     warn("locate_profile has moved to the IPython.paths module")
     from IPython.paths import locate_profile
     return locate_profile(profile=profile)
 
 def expand_path(s):
     """Expand $VARS and ~names in a string, like a shell
 
     :Examples:
 
        In [2]: os.environ['FOO']='test'
 
        In [3]: expand_path('variable FOO is $FOO')
        Out[3]: 'variable FOO is test'
     """
     # This is a pretty subtle hack. When expand user is given a UNC path
     # on Windows (\\server\share$\%username%), os.path.expandvars, removes
     # the $ to get (\\server\share\%username%). I think it considered $
     # alone an empty var. But, we need the $ to remains there (it indicates
     # a hidden share).
     if os.name=='nt':
         s = s.replace('$\\', 'IPYTHON_TEMP')
     s = os.path.expandvars(os.path.expanduser(s))
     if os.name=='nt':
         s = s.replace('IPYTHON_TEMP', '$\\')
     return s
 
 
 def unescape_glob(string):
     """Unescape glob pattern in `string`."""
     def unescape(s):
         for pattern in '*[]!?':
             s = s.replace(r'\{0}'.format(pattern), pattern)
         return s
     return '\\'.join(map(unescape, string.split('\\\\')))
 
 
 def shellglob(args):
     """
     Do glob expansion for each element in `args` and return a flattened list.
 
     Unmatched glob pattern will remain as-is in the returned list.
 
     """
     expanded = []
     # Do not unescape backslash in Windows as it is interpreted as
     # path separator:
     unescape = unescape_glob if sys.platform != 'win32' else lambda x: x
     for a in args:
         expanded.extend(glob.glob(a) or [unescape(a)])
     return expanded
 
 
 def target_outdated(target,deps):
     """Determine whether a target is out of date.
 
     target_outdated(target,deps) -> 1/0
 
     deps: list of filenames which MUST exist.
     target: single filename which may or may not exist.
 
     If target doesn't exist or is older than any file listed in deps, return
     true, otherwise return false.
     """
     try:
         target_time = os.path.getmtime(target)
     except os.error:
         return 1
     for dep in deps:
         dep_time = os.path.getmtime(dep)
         if dep_time > target_time:
             #print "For target",target,"Dep failed:",dep # dbg
             #print "times (dep,tar):",dep_time,target_time # dbg
             return 1
     return 0
 
 
 def target_update(target,deps,cmd):
     """Update a target with a given command given a list of dependencies.
 
     target_update(target,deps,cmd) -> runs cmd if target is outdated.
 
     This is just a wrapper around target_outdated() which calls the given
     command if target is outdated."""
 
     if target_outdated(target,deps):
         system(cmd)
 
 @undoc
 def filehash(path):
     """Make an MD5 hash of a file, ignoring any differences in line
     ending characters."""
     warn("filehash() is deprecated")
     with open(path, "rU") as f:
         return md5(py3compat.str_to_bytes(f.read())).hexdigest()
 
 ENOLINK = 1998
 
 def link(src, dst):
     """Hard links ``src`` to ``dst``, returning 0 or errno.
 
     Note that the special errno ``ENOLINK`` will be returned if ``os.link`` isn't
     supported by the operating system.
     """
 
     if not hasattr(os, "link"):
         return ENOLINK
     link_errno = 0
     try:
         os.link(src, dst)
     except OSError as e:
         link_errno = e.errno
     return link_errno
 
 
 def link_or_copy(src, dst):
     """Attempts to hardlink ``src`` to ``dst``, copying if the link fails.
 
     Attempts to maintain the semantics of ``shutil.copy``.
 
     Because ``os.link`` does not overwrite files, a unique temporary file
     will be used if the target already exists, then that file will be moved
     into place.
     """
 
     if os.path.isdir(dst):
         dst = os.path.join(dst, os.path.basename(src))
 
     link_errno = link(src, dst)
     if link_errno == errno.EEXIST:
         if os.stat(src).st_ino == os.stat(dst).st_ino:
             # dst is already a hard link to the correct file, so we don't need
             # to do anything else. If we try to link and rename the file
             # anyway, we get duplicate files - see http://bugs.python.org/issue21876
             return
 
         new_dst = dst + "-temp-%04X" %(random.randint(1, 16**4), )
         try:
             link_or_copy(src, new_dst)
         except:
             try:
                 os.remove(new_dst)
             except OSError:
                 pass
             raise
         os.rename(new_dst, dst)
     elif link_errno != 0:
         # Either link isn't supported, or the filesystem doesn't support
         # linking, or 'src' and 'dst' are on different filesystems.
         shutil.copy(src, dst)
 
 def ensure_dir_exists(path, mode=0o755):
     """ensure that a directory exists
 
     If it doesn't exist, try to create it and protect against a race condition
     if another process is doing the same.
 
     The default permissions are 755, which differ from os.makedirs default of 777.
     """
     path_exists = False
     try:
         path_exists = os.path.exists(path)
     except UnicodeEncodeError:
-        path = path.encode(sys.getfilesystemencoding() or "utf8")
-        path_exists = os.path.exists(path)
+        try:
+            path = path.encode(sys.getfilesystemencoding() or "utf8")
+            path_exists = os.path.exists(path)
+        except UnicodeEncodeError:
+            path = path.encode("utf8")
+            path_exists = os.path.exists(path)
 
     if not os.path.exists(path):
         try:
             os.makedirs(path, mode=mode)
         except OSError as e:
             if e.errno != errno.EEXIST:
                 raise
     elif not os.path.isdir(path):
         raise IOError("%r exists but is not a directory" % path)