[UPDATE March 2015]
In the meantime there was released a special Unity3D Edition of consulo idea – so the guide below is absolete.
I really love my Mac and I have strong feelings for Unity3D 😀 But what I really dislike is MonoDevelop. I – as Visual Studio veteran – get really an awful pain in my stomach when I work with MonoDevelop. Don’t get me wrong – there was for sure spent a lot of time and skill to create something like MonoDevelop – but it could have been done so much better. Like the JetBrains guys did and created on Mac a number of tools/IDEs that are really a pleasure to use. So I guess you are reading this article because you know what IntelliJ is and would love to use it for C# and Unity3D development.
A coworker pointed me to that solution:
1. – First install the Consulo project Download here from Github. Consulo Is a forked IntelliJ version
2. – Open Consulo and go to Preferences -> Plugins: Install the C# and .NET Core Plugin
3. – Create an empty IntelliJ Project inside of your Unity Project
4. – Now in Consulo go the Modules section and add the .NET library (Version 2.0)
5. – On the same screen click on your binaries panel and add add UnityEngine related .DLLs from your /Applications/Unity/Unity.app/Contents/Frameworks folder
6. – Again on modules select and add Mono .NET 2.0 and your UnityEngine SDK
Voila – here we go. The whole thing is not perfect yet as you can’t compile the project. You can edit and autocomplete your source and have an fast IDE. The project is compile by the Unity later when you deploy or press play.
Have fun!