FIR LC: revisit when to add fields to companion and/or containing class

analysis/symbol-light-classes/src/org/jetbrains/kotlin/light/classes/symbol/classes/FirLightClassForClassOrObjectSymbol.kt

@@ -26,6 +26,7 @@ import org.jetbrains.kotlin.psi.KtClassBody
 import org.jetbrains.kotlin.psi.KtClassOrObject
 import org.jetbrains.kotlin.psi.debugText.getDebugText
 import org.jetbrains.kotlin.psi.stubs.KotlinClassOrObjectStub
+import org.jetbrains.kotlin.utils.addToStdlib.applyIf
 import org.jetbrains.kotlin.utils.addToStdlib.ifFalse
 import org.jetbrains.kotlin.utils.addToStdlib.ifTrue
 
@@ -101,7 +102,9 @@ internal abstract class FirLightClassForClassOrObjectSymbol(
             analyzeWithSymbolAsContext(this) {
                 getDeclaredMemberScope().getCallableSymbols()
                     .filterIsInstance<KtPropertySymbol>()
-                    .filter { it.hasJvmFieldAnnotation() || it.hasJvmStaticAnnotation() || it is KtKotlinPropertySymbol && it.isConst }
+                    .applyIf(isInterface) {
+                        filter { it.hasJvmFieldAnnotation() || it.isConst }
+                    }
                     .mapTo(result) {
                         FirLightFieldForPropertySymbol(
                             propertySymbol = it,
@@ -109,7 +112,7 @@ internal abstract class FirLightClassForClassOrObjectSymbol(
                             containingClass = this@FirLightClassForClassOrObjectSymbol,
                             lightMemberOrigin = null,
                             isTopLevel = false,
-                            forceStatic = !it.hasJvmStaticAnnotation(),
+                            forceStatic = true,
                             takePropertyVisibility = true
                         )
                     }
@@ -117,6 +120,9 @@ internal abstract class FirLightClassForClassOrObjectSymbol(
         }
     }
 
+    private val KtPropertySymbol.isConst: Boolean
+        get() = (this as? KtKotlinPropertySymbol)?.isConst == true
+
     private val _containingFile: PsiFile? by lazyPub {
 
         val kotlinOrigin = kotlinOrigin ?: return@lazyPub null

analysis/symbol-light-classes/src/org/jetbrains/kotlin/light/classes/symbol/classes/FirLightClassForSymbol.kt

@@ -246,7 +246,10 @@ internal open class FirLightClassForSymbol(
             val propertySymbols = classOrObjectSymbol.getDeclaredMemberScope().getCallableSymbols()
                 .filterIsInstance<KtPropertySymbol>()
                 .applyIf(classOrObjectSymbol.isCompanionObject) {
-                    filterNot { it.hasJvmFieldAnnotation() || it is KtKotlinPropertySymbol && it.isConst }
+                    // All fields for companion object of classes are generated to the containing class
+                    // For interfaces, only @JvmField-annotated properties are generated to the containing class
+                    // Probably, the same should work for const vals but it doesn't at the moment (see KT-28294)
+                    filter { containingClass?.isInterface == true && !it.hasJvmFieldAnnotation() }
                 }
             val propertyGroups = propertySymbols.groupBy { it.isFromPrimaryConstructor }