Under some conditions, these methods are required. However, there was a bug in

isfile(). It did not properly handle the case of a path within a mountable archive.

fs/contrib/archivefs.py

@@ -267,6 +267,28 @@ class ArchiveMountFS(mountfs.MountFS):
             return info
         return super(ArchiveMountFS, self).getinfo(path)
 
+    def isdir(self, path):
+        """An isdir() override that allows archives to masquerade as directories. If
+        the path is not an archive, the call is delegated. In the event that the path
+        is an archive, that archive is mounted to ensure it can actually be treated
+        like a directory."""
+        fs, _mount_path, delegate_path = self._delegate(path)
+        if isinstance(fs, ArchiveFS) and path == _mount_path:
+            # If the path is an archive mount point, it is a directory.
+            return True
+        return super(ArchiveMountFS, self).isdir(path)
+
+    def isfile(self, path):
+        """An isfile() override that checks if the given path is a file or not. It is
+        not fooled by a mounted archive. If the path is not an archive, True is returned.
+        If the path is not an archive, the call is delegated."""
+        fs, _mount_path, delegate_path = self._delegate(path)
+        if isinstance(fs, ArchiveFS) and path == _mount_path:
+            # If the path is an archive mount point, it is a file.
+            return True
+        else:
+            return fs.isfile(delegate_path)
+
     def getsize(self, path):
         """A getsize() override that returns the size of an archive. It is not fooled by
         a mounted archive. If the path is not an archive, the call is delegated."""