/usr/share/lua/5.2/lgi/class.lua is in lua-lgi 0.6.2-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/share/lua/5.2/lgi/../../5.1/lgi/class.lua
/usr/share/lua/5.2/lgi/../../5.1/lgi/class.lua