[KLIB tool] Entry point for tests: org.jetbrains.kotlin.cli.klib.Main.exec

^KT-62340

kotlin-native/klib/src/main/kotlin/org/jetbrains/kotlin/cli/klib/main.kt

@@ -2,16 +2,28 @@
  * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
  * that can be found in the LICENSE file.
  */
+@file:JvmName("Main")
 
 package org.jetbrains.kotlin.cli.klib
 
-// TODO: Extract `library` package as a shared jar?
 import kotlin.system.exitProcess
 
-fun main(rawArgs: Array<String>) {
-    val output = KlibToolOutput(stdout = System.out, stderr = System.err)
+/**
+ * This entry point is used in various KLIB dumping tests: dumping IR, dumping metadata, dumping signatures, etc.
+ */
+@Suppress("unused")
+fun exec(stdout: Appendable, stderr: Appendable, args: Array<String>): Int {
+    return execImpl(KlibToolOutput(stdout, stderr), args)
+}
 
+fun main(args: Array<String>) {
+    val exitCode = execImpl(KlibToolOutput(stdout = System.out, stderr = System.err), args)
+    if (exitCode != 0) exitProcess(exitCode)
+}
+
+private fun execImpl(output: KlibToolOutput, rawArgs: Array<String>): Int {
     val args = KlibToolArgumentsParser(output).parseArguments(rawArgs)
+
     if (args != null) {
         val command = when (args.commandName) {
             "dump-abi" -> DumpAbi(output, args)
@@ -37,6 +49,5 @@ fun main(rawArgs: Array<String>) {
         }
     }
 
-    if (output.hasErrors)
-        exitProcess(1)
+    return if (output.hasErrors) 1 else 0
 }