commit https://github.com/vim/vim/commit/73dfe917ba6357413aaf98a021c91add5ac6e9bc Author: Bram Moolenaar <Bram@vim.org> Date: Sat Apr 23 13:54:48 2016 +0200 patch 7.4.1779 Problem: Using negative index in strcharpart(). (Yegappan Lakshmanan) Solution: Assume single byte when using a negative iindex.

For information about installation of Farsi fonts and Vim usage in Farsi mode,
refer to the Farsi help file by typing ":help farsi" in Vim.