190 

   191 def join(path, *paths):

   192     '''Join two or more pathname components, inserting '/' as needed.

   193 

   194     Based on the posix os.path.join() implementation.

   195 

   196     >>> join('foo', 'bar')

   197     'foo/bar'

   198     >>> join('/foo', 'bar')

   199     '/foo/bar'

   200     >>> join('foo', '/bar')

   201     '/bar'

   202     >>> join('foo', 'bar/')

   203     'foo/bar/'

   204     >>> join('foo', 'bar', 'gah')

   205     'foo/bar/gah'

   206     >>> join('foo')

   207     'foo'

   208     >>> join('', 'foo')

   209     'foo'

   210     >>> join('foo/', 'bar')

   211     'foo/bar'

   212     >>> join('', '', '')

   213     ''

   214     >>> join ('foo', '', '', 'bar')

   215     'foo/bar'

   216     '''

   217     sep = '/'

   218     if not paths:

   219         path[:0] + sep #23780: Ensure compatible data type even if p is null.

   220     for piece in paths:

   221         if piece.startswith(sep):

   222             path = piece

   223         elif not path or path.endswith(sep):

   224             path += piece

   225         else:

   226             path += sep + piece

   227     return path

   228 

   229 def dirname(path):

   230     '''returns the directory portion of the given path

   231 

   232     Based on the posix os.path.split() implementation.

   233 

   234     >>> dirname('foo')

   235     ''

   236     >>> dirname('foo/')

   237     'foo'

   238     >>> dirname('foo/bar')

   239     'foo'

   240     >>> dirname('/foo')

   241     '/'

   242     >>> dirname('/foo/bar')

   243     '/foo'

   244     >>> dirname('/foo//bar/poo')

   245     '/foo//bar'

   246     >>> dirname('/foo//bar')

   247     '/foo'

   248     '''

   249     sep = '/'

   250     i = path.rfind(sep) + 1

   251     dirname = path[:i]

   252     if dirname and dirname != sep * len(dirname):

   253         dirname = dirname.rstrip(sep)

   254     return dirname