Detects UI Framework (React Native, Flutter, SwiftUI) used in a simulator build.

FrameworkFinder.kt

import java.io.BufferedReader
import java.io.File
import java.io.InputStreamReader
import kotlin.concurrent.thread

// This script will determine the framework used to build an iOS app.

// Compile: kotlinc FrameworkFinder.kt -include-runtime -d FrameworkFinder.jar
// Usage: java -jar FrameworkFinder.jar <path-to-app-bundle>
// Example: java -jar FrameworkFinder.jar /Users/username/Desktop/MyApp.app

fun main(args: Array<String>) {
    if (args.isEmpty()) {
        println("Please provide a path to the app bundle as an argument.")
        return
    }

    val appBundle = File(args[0])  // Use the first argument as the path.

    if (!appBundle.exists() || !appBundle.isDirectory) {
        println("App bundle does not exist or is not a directory")
        return
    }

    val binaryFile = File(appBundle, appBundle.nameWithoutExtension)

    if (!binaryFile.exists() || !binaryFile.isFile) {
        println("Binary file does not exist or is not a file")
        return
    }

    val process = Runtime.getRuntime().exec("nm ${binaryFile.absolutePath}")
    val reader = BufferedReader(InputStreamReader(process.inputStream))
    var output = ""

    val readThread = thread {
        output = reader.use { it.readText() }
    }

    // Wait for the process to finish.
    process.waitFor()

    // Wait for the output to be read.
    readThread.join()

    when {
        output.contains("_OBJC_CLASS_\$_UIHostingView") -> {
            println("The app is an iOS app built using *SwiftUI*")
        }
        output.contains("_OBJC_CLASS_\$_Flutter") -> {
            println("The app is an iOS app built using *Flutter*")
        }
        output.contains("_OBJC_CLASS_\$_RCTRootView") -> {
            println("The app is an iOS app built using *React Native*")
        }
        else -> {
            println("The app was not built using React Native, Flutter, or SwiftUI")
        }
    }
}