Java path for kotlin tests compilation on Windows machines

core/src/main/kotlin/org/jetbrains/research/testspark/core/test/kotlin/KotlinTestCompiler.kt

@@ -13,9 +13,12 @@ class KotlinTestCompiler(
     libPaths: List<String>,
     junitLibPaths: List<String>,
     kotlinSDKHomeDirectory: String,
+    javaHomeDirectoryPath: String,
 ) : TestCompiler(libPaths, junitLibPaths) {
     private val logger = KotlinLogging.logger { this::class.java }
     private val kotlinc: String
+    // Direct declaration in constructor requires changes to TestCompiler, so we declare it here.
+    private val javaHomeDirectoryPath = javaHomeDirectoryPath
 
     // init block to find the kotlinc compiler
     init {
@@ -55,9 +58,14 @@ class KotlinTestCompiler(
         logger.info { "[KotlinTestCompiler] Compiling ${path.substringAfterLast('/')}" }
 
         val classPaths = "\"${getClassPaths(projectBuildPath)}\""
+
+        // We need to ensure JAVA is in the path variable
+        // See: https://github.com/JetBrains-Research/TestSpark/issues/410
+        val setJavaPathOnWindows = "set PATH=%PATH%;$javaHomeDirectoryPath\\bin\\&&"
+
         // Compile file
         // See: https://github.com/JetBrains-Research/TestSpark/issues/402
-        val kotlinc = if (DataFilesUtil.isWindows()) "\"$kotlinc\"" else "'$kotlinc'"
+        val kotlinc = if (DataFilesUtil.isWindows()) "$setJavaPathOnWindows\"$kotlinc\"" else "'$kotlinc'"
 
         val executionResult = CommandLineRunner.run(
             arrayListOf(

src/main/kotlin/org/jetbrains/research/testspark/tools/factories/TestCompilerFactory.kt

@@ -24,33 +24,41 @@ object TestCompilerFactory {
 
         // TODO add the warning window that for Java we always need the javaHomeDirectoryPath
         return when (language) {
-            SupportedLanguage.Java -> createJavaCompiler(project, libraryPaths, junitLibraryPaths, javaHomeDirectory)
-            SupportedLanguage.Kotlin -> createKotlinCompiler(libraryPaths, junitLibraryPaths)
+            SupportedLanguage.Java -> {
+                val javaSDKHomePath = findJavaSDKHomePath(javaHomeDirectory, project)
+                JavaTestCompiler(libraryPaths, junitLibraryPaths, javaSDKHomePath)
+            }
+            SupportedLanguage.Kotlin -> {
+                val javaSDKHomePath = findJavaSDKHomePath(javaHomeDirectory, project) // Kotlinc relies on java to compile kotlin files.
+                val kotlinSDKHomeDirectory = KotlinPluginLayout.kotlinc.absolutePath
+                KotlinTestCompiler(libraryPaths, junitLibraryPaths, kotlinSDKHomeDirectory, javaSDKHomePath)
+            }
         }
     }
 
-    private fun createJavaCompiler(
+    /**
+     * Finds the home path of the Java SDK.
+     *
+     * @param javaHomeDirectory The directory where Java SDK is installed. If null, the project's configured SDK path is used.
+     * @param project The project for which the Java SDK home path is being determined.
+     * @return The home path of the Java SDK.
+     * @throws JavaSDKMissingException If no Java SDK is configured for the project.
+     */
+    private fun findJavaSDKHomePath(
+        javaHomeDirectory: String?,
         project: Project,
-        libraryPaths: List<String>,
-        junitLibraryPaths: List<String>,
-        javaHomeDirectory: String? = null,
-    ): JavaTestCompiler {
-        val javaSDKHomePath = javaHomeDirectory
-            ?: ProjectRootManager.getInstance(project).projectSdk?.homeDirectory?.path
+    ): String {
+        val javaSDKHomePath =
+            javaHomeDirectory
+                ?: ProjectRootManager
+                    .getInstance(project)
+                    .projectSdk
+                    ?.homeDirectory
+                    ?.path
 
         if (javaSDKHomePath == null) {
             throw JavaSDKMissingException(LLMMessagesBundle.get("javaSdkNotConfigured"))
         }
-
-        return JavaTestCompiler(libraryPaths, junitLibraryPaths, javaSDKHomePath)
-    }
-
-    private fun createKotlinCompiler(
-        libraryPaths: List<String>,
-        junitLibraryPaths: List<String>,
-    ): KotlinTestCompiler {
-        // kotlinc should be under `[kotlinSDKHomeDirectory]/bin/kotlinc`
-        val kotlinSDKHomeDirectory = KotlinPluginLayout.kotlinc.absolutePath
-        return KotlinTestCompiler(libraryPaths, junitLibraryPaths, kotlinSDKHomeDirectory)
+        return javaSDKHomePath
     }
 }