LuaCheck 代码静态分析

$ sudo luarocks install luacheck

$ luacheck -h
...
Links:

   Luacheck on GitHub: https://github.com/mpeterv/luacheck
   Luacheck documentation: https://luacheck.readthedocs.org

$ luacheck test.lua

test.lua:18:27: accessing undefined variable html
test.lua:22:1: setting non-standard global variable log
test.lua:23:121: line is too long (257 > 120)
test.lua:26:27: accessing undefined variable log