You will need the following:
gluac — gluac is a variant of luac, which parses (Garry's Mod) lua files. It can be used for detecting errors in (Garry's Mod) lua scripts. See http://www.lua.org/manual/4.0/luac.html for more informations about luac.
This package will lint your currently open
.lua files in Atom through gluac. It will lint on edit and/or save, so you are able to immediately see any errors in your script.
Due to the behavior of luac, it will only notify you of the first error found in the file.
$ apm install linter (if you don't have Atom Linter installed).
$ apm install linter-glua
Atom -> Preferences... -> Packages -> Linter lua -> Settings:
gluacexecutable, if not on your system's PATH environment variable.
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.