/usr/share/lua/5.2/cosmo/grammar.lua is in lua-cosmo 13.01.30-2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/lua/5.2/cosmo/../../5.1/cosmo/grammar.lua
/usr/share/lua/5.2/cosmo/../../5.1/cosmo/grammar.lua