Sort modifiers: process final modifier correctly #KT-22954 fixed

idea/src/org/jetbrains/kotlin/idea/inspections/SortModifiersInspection.kt

@@ -9,6 +9,7 @@ import com.intellij.codeInspection.*
 import com.intellij.openapi.project.Project
 import com.intellij.psi.PsiElementVisitor
 import org.jetbrains.kotlin.lexer.KtModifierKeywordToken
+import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
 import org.jetbrains.kotlin.psi.addRemoveModifier.sortModifiers
 import org.jetbrains.kotlin.psi.psiUtil.allChildren
@@ -34,6 +35,8 @@ class SortModifiersInspection : AbstractKotlinInspection(), CleanupLocalInspecti
                 val modifiers = modifierElements.mapNotNull { it.node.elementType as? KtModifierKeywordToken }.toList()
                 if (modifiers.isEmpty()) return
 
+                val startElement = modifierElements.firstOrNull { it.node.elementType is KtModifierKeywordToken } ?: return
+
                 val sortedModifiers = sortModifiers(modifiers)
                 if (modifiers == sortedModifiers && !modifiersBeforeAnnotations) return
 
@@ -41,12 +44,16 @@ class SortModifiersInspection : AbstractKotlinInspection(), CleanupLocalInspecti
                     "Modifiers should follow annotations"
                 else
                     "Non-canonical modifiers order"
-                holder.registerProblem(
+
+                val descriptor = holder.manager.createProblemDescriptor(
+                    startElement,
                     list,
                     message,
                     ProblemHighlightType.GENERIC_ERROR_OR_WARNING,
+                    isOnTheFly,
                     SortModifiersFix(sortedModifiers)
                 )
+                holder.registerProblem(descriptor)
             }
         }
     }
@@ -62,7 +69,10 @@ private class SortModifiersFix(private val modifiers: List<KtModifierKeywordToke
         val owner = list.parent as? KtModifierListOwner ?: return
 
         modifiers.forEach { owner.removeModifier(it) }
-        modifiers.forEach { owner.addModifier(it) }
+        modifiers
+            .partition { it == KtTokens.FINAL_KEYWORD }
+            .let { it.second + it.first }
+            .forEach { owner.addModifier(it) }
     }
 }