Fix support for files outside of site root directory on Windows

Author: Kwpolska

CHANGES.txt

@@ -17,6 +17,7 @@ Features
 Bugfixes
 --------
 
+* Fix support for files outside of site root directory on Windows
 * Support passing ``--backend`` and ``--db-file`` to ``nikola auto``
 * Support blank values in certain WordPress-imported structures
   (Issue #3535)

nikola/post.py

@@ -253,7 +253,7 @@ def _set_paths(self, source_path):
         self.post_name = os.path.splitext(source_path)[0]  # posts/blah
         _relpath = os.path.relpath(self.post_name)
         if _relpath != self.post_name:
-            self.post_name = _relpath.replace('..' + os.sep, '_..' + os.sep)
+            self.post_name = _relpath.replace('..' + os.sep, '__dotdot__' + os.sep)
         # cache[\/]posts[\/]blah.html
         self.base_path = os.path.join(self.config['CACHE_FOLDER'], self.post_name + ".html")
         # cache/posts/blah.html