bpo-38807: Add os.PathLike to exception message raised by _check_arg_types (GH-17160) (GH-17249)

(cherry picked from commit fe75b62575)

Co-authored-by: Tomás Farías <tomasfariassantana@gmail.com>

Lib/genericpath.py

@@ -149,7 +149,7 @@ def _check_arg_types(funcname, *args):
         elif isinstance(s, bytes):
             hasbytes = True
         else:
-            raise TypeError('%s() argument must be str or bytes, not %r' %
-                            (funcname, s.__class__.__name__)) from None
+            raise TypeError(f'{funcname}() argument must be str, bytes, or '
+                            f'os.PathLike object, not {s.__class__.__name__!r}') from None
     if hasstr and hasbytes:
         raise TypeError("Can't mix strings and bytes in path components") from None

Misc/NEWS.d/next/Library/2019-11-15-09-30-29.bpo-38807.PsmRog.rst

@@ -0,0 +1 @@
+Update :exc:`TypeError` messages for :meth:`os.path.join` to include :class:`os.PathLike` objects as acceptable input types.