'Build input file cannot be found' Swift 4.2, Xcode 10.0

Question

I am getting the following error when building in Xcode 10.0 with swift 4.2:

Answer 1

In my case I got this error when I renamed a ViewController name using Refactor. The view controller name occurrences were changed but the real file not.

I tried to do what @ajji said but it didn't work. So I changed the name of the real file. After that all worked like a charm