Lib/macurl2path.py

   1 """Macintosh-specific module for conversion between pathnames and URLs.
   2
   3 Do not import directly; use urllib instead."""
   4
   5 import urllib.parse
   6 import os
   7
   8 __all__ = ["url2pathname","pathname2url"]
   9
  10 def url2pathname(pathname):
  11     """OS-specific conversion from a relative URL of the 'file' scheme
  12     to a file system path; not recommended for general use."""
  13     #
  14     # XXXX The .. handling should be fixed...
  15     #
  16     tp = urllib.parse.splittype(pathname)[0]
  17     if tp and tp != 'file':
  18         raise RuntimeError('Cannot convert non-local URL to pathname')
  19     # Turn starting /// into /, an empty hostname means current host
  20     if pathname[:3] == '///':
  21         pathname = pathname[2:]
  22     elif pathname[:2] == '//':
  23         raise RuntimeError('Cannot convert non-local URL to pathname')
  24     components = pathname.split('/')
  25     # Remove . and embedded ..
  26     i = 0
  27     while i < len(components):
  28         if components[i] == '.':
  29             del components[i]
  30         elif components[i] == '..' and i > 0 and \
  31                                   components[i-1] not in ('', '..'):
  32             del components[i-1:i+1]
  33             i = i-1
  34         elif components[i] == '' and i > 0 and components[i-1] != '':
  35             del components[i]
  36         else:
  37             i = i+1
  38     if not components[0]:
  39         # Absolute unix path, don't start with colon
  40         rv = ':'.join(components[1:])
  41     else:
  42         # relative unix path, start with colon. First replace
  43         # leading .. by empty strings (giving ::file)
  44         i = 0
  45         while i < len(components) and components[i] == '..':
  46             components[i] = ''
  47             i = i + 1
  48         rv = ':' + ':'.join(components)
  49     # and finally unquote slashes and other funny characters
  50     return urllib.parse.unquote(rv)
  51
  52 def pathname2url(pathname):
  53     """OS-specific conversion from a file system path to a relative URL
  54     of the 'file' scheme; not recommended for general use."""
  55     if '/' in pathname:
  56         raise RuntimeError("Cannot convert pathname containing slashes")
  57     components = pathname.split(':')
  58     # Remove empty first and/or last component
  59     if components[0] == '':
  60         del components[0]
  61     if components[-1] == '':
  62         del components[-1]
  63     # Replace empty string ('::') by .. (will result in '/../' later)
  64     for i in range(len(components)):
  65         if components[i] == '':
  66             components[i] = '..'
  67     # Truncate names longer than 31 bytes
  68     components = map(_pncomp2url, components)
  69
  70     if os.path.isabs(pathname):
  71         return '/' + '/'.join(components)
  72     else:
  73         return '/'.join(components)
  74
  75 def _pncomp2url(component):
  76     # We want to quote slashes
  77     return urllib.parse.quote(component[:31], safe='')
  78
  79 def test():
  80     for url in ["index.html",
  81                 "bar/index.html",
  82                 "/foo/bar/index.html",
  83                 "/foo/bar/",
  84                 "/"]:
  85         print('%r -> %r' % (url, url2pathname(url)))
  86     for path in ["drive:",
  87                  "drive:dir:",
  88                  "drive:dir:file",
  89                  "drive:file",
  90                  "file",
  91                  ":file",
  92                  ":dir:",
  93                  ":dir:file"]:
  94         print('%r -> %r' % (path, pathname2url(path)))
  95
  96 if __name__ == '__main__':
  97     test()