Set java.class.path property in runner and loader

#KT-24991 fixed

compiler/cli/cli-runner/src/org/jetbrains/kotlin/runner/runners.kt

@@ -58,6 +58,7 @@ abstract class AbstractRunner : Runner {
         }
 
         Thread.currentThread().contextClassLoader = classLoader
+        val savedClasspathProperty = System.setProperty("java.class.path", classpath.joinToString(File.pathSeparator))
 
         try {
             main.invoke(null, arguments.toTypedArray())
@@ -68,6 +69,10 @@ abstract class AbstractRunner : Runner {
         catch (e: InvocationTargetException) {
             throw e.targetException
         }
+        finally {
+            if (savedClasspathProperty == null) System.clearProperty("java.class.path")
+            else System.setProperty("java.class.path", savedClasspathProperty)
+        }
     }
 }
 

compiler/preloader/src/org/jetbrains/kotlin/preloading/Preloader.java

@@ -26,6 +26,7 @@ import java.net.MalformedURLException;
 import java.net.URL;
 import java.net.URLClassLoader;
 import java.util.*;
+import java.util.stream.Collectors;
 
 @SuppressWarnings("UseOfSystemOutOrSystemErr")
 public class Preloader {
@@ -64,6 +65,8 @@ public class Preloader {
         Method mainMethod = mainClass.getMethod("main", String[].class);
 
         Thread.currentThread().setContextClassLoader(preloaded);
+        String classPathString = options.classpath.stream().map(File::getPath).collect(Collectors.joining(File.pathSeparator));
+        String savedClasspathProperty = System.setProperty("java.class.path", classPathString);
 
         Runtime.getRuntime().addShutdownHook(
                 new Thread(new Runnable() {
@@ -79,8 +82,14 @@ public class Preloader {
                 })
         );
 
-        //noinspection SSBasedInspection
-        mainMethod.invoke(0, (Object) options.arguments.toArray(new String[options.arguments.size()]));
+        try {
+            //noinspection SSBasedInspection
+            mainMethod.invoke(0, (Object) options.arguments.toArray(new String[options.arguments.size()]));
+        }
+        finally {
+            if (savedClasspathProperty == null) System.clearProperty("java.class.path");
+            else System.setProperty("java.class.path", savedClasspathProperty);
+        }
     }
 
     private static ClassLoader createClassLoader(Options options) throws MalformedURLException {

compiler/testData/launcher/classPathPropTest.kts

@@ -0,0 +1,9 @@
+package test
+
+import java.io.File
+
+val classPathFromProp = System.getProperty("java.class.path")
+
+val jarFromProps = classPathFromProp.split(File.pathSeparator).firstOrNull { it.contains("kotlin-compiler") }
+
+println(jarFromProps?.let { File(it).name } ?: "kotlin-compiler not found in the java.class.path property: $classPathFromProp")

compiler/testData/launcher/contextClassLoaderTester.kt

@@ -1,11 +1,19 @@
 
+import java.io.File
+
 object ContextClassLoaderTester {
 
     @JvmStatic
     fun main(args: Array<String>) {
         kotlin.test.DefaultAsserter.assertTrue("", true) // this tests that kotlin-test is in the compilation and runtime classpaths
+
         val contextClassLoader = Thread.currentThread().getContextClassLoader()
         contextClassLoader.loadClass("kotlin.test.DefaultAsserter") // this tests that thread context classloader is set correctly
-        println("ok")
+
+        val classPathFromProp = System.getProperty("java.class.path")
+
+        val jarFromProps = classPathFromProp.split(File.pathSeparator).firstOrNull { it.contains("kotlin-test") }
+
+        println(jarFromProps?.let { File(it).name } ?: "kotlin-test.jar not found in the java.class.path property: $classPathFromProp")
     }
 }

compiler/testData/launcher/helloWorld.kts

@@ -1,3 +0,0 @@
-package test
-
-println("Hello!")

compiler/tests/org/jetbrains/kotlin/cli/LauncherScriptTest.kt

@@ -79,12 +79,12 @@ class LauncherScriptTest : TestCaseWithTmpdir() {
         )
     }
 
-    fun testKotlincJvmSimpleScript() {
+    fun testKotlincJvmScriptWithClassPathFromSysProp() {
         runProcess(
             "kotlinc-jvm",
             "-script",
-            "$testDataDirectory/helloWorld.kts",
-            expectedStdout = "Hello!\n"
+            "$testDataDirectory/classPathPropTest.kts",
+            expectedStdout = "kotlin-compiler.jar\n"
         )
     }
 
@@ -102,7 +102,7 @@ class LauncherScriptTest : TestCaseWithTmpdir() {
             "kotlin",
             "-cp", listOf(tmpdir.path, kotlinTestJar.path).joinToString(File.pathSeparator),
             "ContextClassLoaderTester",
-            expectedStdout = "ok\n"
+            expectedStdout = "${kotlinTestJar.name}\n"
         )
     }