Safe Delete: Fixed usages search when applied to simple enum entries

#KT-11816 Fixed

ChangeLog.md

@@ -34,6 +34,7 @@ Issues fixed:
 - [KT-8817](https://youtrack.jetbrains.com/issue/KT-8817) Fixed rename of Java getters/setters through synthetic property references in Kotlin
 - [KT-11617](https://youtrack.jetbrains.com/issue/KT-11617) Fixed title of Introduce Parameter declaration chooser
 - [KT-11817](https://youtrack.jetbrains.com/issue/KT-11817) Fixed rename of Kotlin enum constants through Java references
+- [KT-11816](https://youtrack.jetbrains.com/issue/KT-11816) Fixed usages search for Safe Delete on simple enum entries
 
 #### Debugger
 

compiler/light-classes/src/org/jetbrains/kotlin/asJava/LightClassUtil.kt

@@ -80,7 +80,7 @@ object LightClassUtil {
         return extractPropertyAccessors(property, getterWrapper, setterWrapper)
     }
 
-    private fun getLightClassBackingField(declaration: KtDeclaration): PsiField? {
+    fun getLightClassBackingField(declaration: KtDeclaration): PsiField? {
         var psiClass: PsiClass = getWrappingClass(declaration) ?: return null
 
         if (psiClass is KtLightClass) {

idea/src/org/jetbrains/kotlin/idea/refactoring/safeDelete/KotlinSafeDeleteProcessor.kt

@@ -185,6 +185,10 @@ class KotlinSafeDeleteProcessor : JavaSafeDeleteProcessor() {
 
         return when (element) {
             is KtClassOrObject -> {
+                if (element is KtEnumEntry) {
+                    LightClassUtil.getLightClassBackingField(element)?.let { findUsagesByJavaProcessor(it, false) }
+                }
+
                 element.toLightClass()?.let { klass ->
                     findDelegationCallUsages(klass)
                     findUsagesByJavaProcessor(klass, false)

idea/testData/refactoring/safeDelete/deleteClass/kotlinClass/enumEntry.kt

@@ -0,0 +1,5 @@
+enum class EnumTarget { <caret>RED, GREEN, BLUE }
+
+fun refer(p: EnumTarget) {
+    println(p == EnumTarget.RED)
+}

idea/testData/refactoring/safeDelete/deleteClass/kotlinClass/enumEntry.kt.messages

@@ -0,0 +1 @@
+class EnumTarget.RED has 1 usage that is not safe to delete.

idea/tests/org/jetbrains/kotlin/idea/refactoring/safeDelete/SafeDeleteTestGenerated.java

@@ -67,6 +67,12 @@ public class SafeDeleteTestGenerated extends AbstractSafeDeleteTest {
             doClassTest(fileName);
         }
 
+        @TestMetadata("enumEntry.kt")
+        public void testEnumEntry() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/safeDelete/deleteClass/kotlinClass/enumEntry.kt");
+            doClassTest(fileName);
+        }
+
         @TestMetadata("localClass1.kt")
         public void testLocalClass1() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/safeDelete/deleteClass/kotlinClass/localClass1.kt");