issue27186: add C version of os.fspath(); patch by Jelle Zijlstra

Lib/os.py

@@ -1104,23 +1104,24 @@ def fdopen(fd, *args, **kwargs):
     import io
     return io.open(fd, *args, **kwargs)
 
-# Supply os.fspath()
-def fspath(path):
-    """Return the string representation of the path.
+# Supply os.fspath() if not defined in C
+if not _exists('fspath'):
+    def fspath(path):
+        """Return the string representation of the path.
 
-    If str or bytes is passed in, it is returned unchanged.
-    """
-    if isinstance(path, (str, bytes)):
-        return path
+        If str or bytes is passed in, it is returned unchanged.
+        """
+        if isinstance(path, (str, bytes)):
+            return path
 
-    # Work from the object's type to match method resolution of other magic
-    # methods.
-    path_type = type(path)
-    try:
-        return path_type.__fspath__(path)
-    except AttributeError:
-        if hasattr(path_type, '__fspath__'):
-            raise
+        # Work from the object's type to match method resolution of other magic
+        # methods.
+        path_type = type(path)
+        try:
+            return path_type.__fspath__(path)
+        except AttributeError:
+            if hasattr(path_type, '__fspath__'):
+                raise
 
-        raise TypeError("expected str, bytes or os.PathLike object, not "
-                        + path_type.__name__)
+            raise TypeError("expected str, bytes or os.PathLike object, not "
+                            + path_type.__name__)