$ cat ~/Desktop/test.swift
import SwiftUI

struct ContentView: View {
    var body: some View {
        ZStack {
            if let status = Warning.which {
                RoundedRectangle(cornerRadius: 10)
                    .foregroundColor(status == .three ? Color.red : status == .two ? Color.yellow : Color.white)
            }
        }
        #^COMPLETE^#
    }
}

enum Warning {
    case one
    case two
    case three

    static var which: Warning {
        fatalError()
    }
}
$ time ./swift-ide-test --code-completion -source-filename ~/Desktop/test.swift -sdk /Applications/Xcode-GPE.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator14.5.sdk -target x86_64-apple-ios14.0-simulator -code-completion-token=COMPLETE > /dev/null
found code completion token COMPLETE at offset 326
________________________________________________________
Executed in    2.15 secs   fish           external 
   usr time    1.95 secs  110.00 micros    1.95 secs 
   sys time    0.19 secs  1009.00 micros    0.19 secs