tpope/vim-obsession — pull request #9 by monokrome (2013-05-01 22:37:21+00:00)
Title: Fixed an issue occurring when the path passed to :Obsession is a symlink

When passed a path including a symlink to obsession, `expand` will "fail" and return empty. To avoid this, you can check if the result file is empty and pass the result through `fnamemodify` instead. This seems to have solved the problem.