FileLink should accept PathLike objects

Starting with Python 3.6, the os.PathLike interface was introduced so that functions which operate on paths would accept not only str or bytes, but also pathlib.PurePath for example.

IPython.display.FileLink does not accept PathLike objects yet:

[In]: IPython.display.FileLink(pathlib.Path(r'C:\Windows\System32\drivers\etc\hosts'))
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
C:\mnt\Anaconda\5.1.0\lib\site-packages\IPython\core\formatters.py in __call__(self, obj)
    343             method = get_real_method(obj, self.print_method)
    344             if method is not None:
--> 345                 return method()
    346             return None
    347         else:

C:\mnt\Anaconda\5.1.0\lib\site-packages\IPython\lib\display.py in _repr_html_(self)
    355                     "incorrect path." % self.path)
    356 
--> 357         return self._format_path()
    358 
    359     def __repr__(self):

C:\mnt\Anaconda\5.1.0\lib\site-packages\IPython\lib\display.py in _format_path(self)
    341 
    342     def _format_path(self):
--> 343         fp = ''.join([self.url_prefix,self.path])
    344         return ''.join([self.result_html_prefix,
    345                         self.html_link_str % (fp, self.path),

TypeError: sequence item 1: expected str instance, WindowsPath found

This could be implemented by calling os.fspath on the parameter, but care should be taken because the function did not exist before Python 3.6.

Also for what it’s worth pathlib objects have a method named as_uri().

[ciupicri]

I was think of something like:

try:
    from os import fsencode
except ImportError:
    fsencode = lamda path: path  # do nothing just like in previous versions

And call fsencode where it’s needed. Another possibility would be to make fsencode = str in the fallback, as you suggest.

[takluyver]

Closed b y #11060.