I am a big fun of intellij idea. So i integrate defold api with it.
To use Idea with lua and defold your need.
1)Install lua plugin. EmmyLua https://plugins.jetbrains.com/plugin/9768-emmylua
2)Edit file associations. Press ctrl + shift + a. Then enter command Edit file associations. To lua language add .*script .*render_script .*gui_script.
3)Download defold api library.
I create a tool that parse defold docs and generate lua files with description.
You need download zip file Releases · d954mas/defold-api-emmylua · GitHub
4)Add library to your project.
File/Project structure/libraries/lua zip library.
5)Use it =)