firebase-ios-sdk/Sources/firebase-test/main.swift

import Foundation
import FirebaseCore
import GoogleUtilities_Environment
import GoogleUtilities_Logger

print("Hello world!")
print("Is app store receipt sandbox? Answer: \(GULAppEnvironmentUtil.isAppStoreReceiptSandbox())")
print("Is from app store? Answer: \(GULAppEnvironmentUtil.isFromAppStore())")
print("Is this the simulator? Answer: \(GULAppEnvironmentUtil.isSimulator())")
print("Device model? Answer: \(GULAppEnvironmentUtil.deviceModel() ?? "NONE")")
print("System version? Answer: \(GULAppEnvironmentUtil.systemVersion() ?? "NONE")")
print("Is App extension? Answer: \(GULAppEnvironmentUtil.isAppExtension())")
print("Is iOS 7 or higher? Answer: \(GULAppEnvironmentUtil.isIOS7OrHigher())")

print("Is there a default app? Answer: \(FirebaseApp.app() != nil)")