KtFile.getClasses() returns empty array for non-jvm files

idea/idea-analysis/src/org/jetbrains/kotlin/idea/caches/resolve/KtFileClassProviderImpl.kt

@@ -12,11 +12,13 @@ import org.jetbrains.kotlin.asJava.classes.KtLightClassForFacade
 import org.jetbrains.kotlin.asJava.toLightClass
 import org.jetbrains.kotlin.fileClasses.JvmFileClassUtil
 import org.jetbrains.kotlin.fileClasses.javaFileFacadeFqName
+import org.jetbrains.kotlin.idea.caches.project.getModuleInfo
 import org.jetbrains.kotlin.idea.caches.resolve.util.isInDumbMode
 import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.psi.KtFile
 import org.jetbrains.kotlin.psi.KtFileClassProvider
 import org.jetbrains.kotlin.psi.analysisContext
+import org.jetbrains.kotlin.resolve.jvm.platform.JvmPlatform
 
 class KtFileClassProviderImpl(val kotlinAsJavaSupport: KotlinAsJavaSupport) :
     KtFileClassProvider {
@@ -33,7 +35,13 @@ class KtFileClassProviderImpl(val kotlinAsJavaSupport: KotlinAsJavaSupport) :
         val result = arrayListOf<PsiClass>()
         file.declarations.filterIsInstance<KtClassOrObject>().map { it.toLightClass() }.filterNotNullTo(result)
 
-        val moduleInfo = file.getModuleInfoPreferringJvmPlatform()
+        val moduleInfo = file.getModuleInfo()
+        // prohibit obtaining light classes for non-jvm modules trough KtFiles
+        // common files might be in fact compiled to jvm and thus correspond to a PsiClass
+        // this API does not provide context (like GSS) to be able to determine if this file is in fact seen through a jvm module
+        // this also fixes a problem where a Java JUnit run configuration producer would produce run configurations for a common file
+        if (moduleInfo.platform !is JvmPlatform) return emptyArray()
+
         val jvmClassInfo = JvmFileClassUtil.getFileClassInfoNoResolve(file)
         val fileClassFqName = file.javaFileFacadeFqName
 

idea/tests/org/jetbrains/kotlin/asJava/KtFileLightClassTest.kt

@@ -28,6 +28,7 @@ import org.jetbrains.kotlin.idea.test.KotlinLightCodeInsightFixtureTestCase
 import org.jetbrains.kotlin.idea.test.KotlinLightProjectDescriptor
 import org.jetbrains.kotlin.idea.test.PluginTestCaseBase
 import org.jetbrains.kotlin.name.FqName
+import org.jetbrains.kotlin.psi.KtClass
 import org.jetbrains.kotlin.psi.KtFile
 
 class KtFileLightClassTest : KotlinLightCodeInsightFixtureTestCase() {
@@ -93,7 +94,7 @@ class KtFileLightClassTest : KotlinLightCodeInsightFixtureTestCase() {
 
         val injectedFile = (editor as? EditorWindow)?.injectedFile
         assertEquals("Wrong injection language", "kotlin", injectedFile?.language?.id)
-        assertEquals("Injected class should be `A`", "A", (injectedFile as KtFile).classes.single().name)
+        assertEquals("Injected class should be `A`", "A", ((injectedFile as KtFile).declarations.single() as KtClass).toLightClass()!!.name)
     }