Making kts-compiler able to dig out the ClassPath from the intellij PluginClassLoader

libraries/scripting/jvm/src/kotlin/script/experimental/jvm/util/jvmClasspathUtil.kt

@@ -43,7 +43,7 @@ internal const val KOTLIN_SCRIPT_RUNTIME_JAR_PROPERTY = "kotlin.script.runtime.j
 private val validClasspathFilesExtensions = setOf("jar", "zip", "java")
 
 fun classpathFromClassloader(classLoader: ClassLoader): List<File>? =
-    generateSequence(classLoader) { it.parent }.toList().flatMap {
+    allRelatedClassLoaders(classLoader).toList().flatMap {
         val urls = (it as? URLClassLoader)?.urLs?.asList()
             ?: try {
                 // e.g. for IDEA platform UrlClassLoader
@@ -89,6 +89,24 @@ fun File.hasParentNamed(baseName: String): Boolean =
 
 private const val KOTLIN_COMPILER_EMBEDDABLE_JAR = "$KOTLIN_COMPILER_NAME-embeddable.jar"
 
+private fun allRelatedClassLoaders(clsLoader: ClassLoader, visited: MutableSet<ClassLoader> = HashSet()): Sequence<ClassLoader> {
+    if (!visited.add(clsLoader)) return emptySequence()
+
+    val singleParent = clsLoader.parent
+    if (singleParent != null)
+        return sequenceOf(clsLoader) + sequenceOf(singleParent).flatMap { allRelatedClassLoaders(it, visited) }
+
+    return try {
+        val field = clsLoader.javaClass.getDeclaredField("myParents") // com.intellij.ide.plugins.cl.PluginClassLoader
+        field.isAccessible = true
+        val arrayOfClassLoaders = field.get(clsLoader) as Array<ClassLoader>
+        sequenceOf(clsLoader) + arrayOfClassLoaders.asSequence().flatMap { allRelatedClassLoaders(it, visited) }
+    } catch (e: Throwable) {
+        sequenceOf(clsLoader)
+    }
+}
+
+
 internal fun List<File>.takeIfContainsAll(vararg keyNames: String): List<File>? =
         takeIf { classpath ->
             keyNames.all { key -> classpath.any { it.matchMaybeVersionedFile(key) } }