Introduce CallableId.asSingleFqName and use it instead CallableId.asFqNameForDebugInfo

compiler/frontend.common/src/org/jetbrains/kotlin/diagnostics/WhenMissingCase.kt

@@ -51,7 +51,7 @@ sealed class WhenMissingCase {
     }
 
     class EnumCheckIsMissing(val callableId: CallableId) : WhenMissingCase() {
-        override val branchConditionText: String = callableId.asFqNameForDebugInfo().toString()
+        override val branchConditionText: String = callableId.asSingleFqName().toString()
 
         override fun toString(): String {
             return callableId.callableName.identifier

core/compiler.common/src/org/jetbrains/kotlin/name/CallableId.kt

@@ -54,7 +54,10 @@ data class CallableId(
 
     fun asFqNameForDebugInfo(): FqName {
         if (pathToLocal != null) return pathToLocal.child(callableName)
+        return asSingleFqName()
+    }
 
+    fun asSingleFqName(): FqName {
         return classId?.asSingleFqName()?.child(callableName) ?: packageName.child(callableName)
     }
 

idea/idea-core/src/org/jetbrains/kotlin/idea/core/Utils.kt

@@ -172,7 +172,7 @@ fun FqName.quoteSegmentsIfNeeded(): String {
 fun FqName.quoteIfNeeded() = FqName(quoteSegmentsIfNeeded())
 
 fun CallableId.asFqNameWithRootPrefixIfNeeded() =
-    asFqNameForDebugInfo().withRootPrefixIfNeeded()
+    asSingleFqName().withRootPrefixIfNeeded()
 
 fun FqName.withRootPrefixIfNeeded(targetElement: KtElement? = null) =
     if (canAddRootPrefix() && targetElement?.canAddRootPrefix() != false)

idea/idea-fir/src/org/jetbrains/kotlin/idea/completion/KotlinFirLookupElementFactory.kt

@@ -370,7 +370,7 @@ private fun addCallableImportIfRequired(targetFile: KtFile, nameToImport: Callab
 }
 
 private fun alreadyHasImport(file: KtFile, nameToImport: CallableId): Boolean {
-    if (file.importDirectives.any { it.importPath?.fqName == nameToImport.asFqNameForDebugInfo() }) return true
+    if (file.importDirectives.any { it.importPath?.fqName == nameToImport.asSingleFqName() }) return true
 
     withAllowedResolve {
         analyse(file) {

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/fir/FirIdeDeserializedDeclarationSourceProvider.kt

@@ -42,7 +42,7 @@ object FirIdeDeserializedDeclarationSourceProvider {
     ): PsiElement? {
         val candidates = if (function.isTopLevel) {
             KotlinTopLevelFunctionFqnNameIndex.getInstance().get(
-                function.symbol.callableId.asFqNameForDebugInfo().asString(),
+                function.symbol.callableId.asSingleFqName().asString(),
                 project,
                 function.scope(project)
             ).filter(KtNamedFunction::isCompiled)
@@ -58,7 +58,7 @@ object FirIdeDeserializedDeclarationSourceProvider {
     private fun provideSourceForProperty(property: FirProperty, project: Project): PsiElement? {
         val candidates = if (property.isTopLevel) {
             KotlinTopLevelFunctionFqnNameIndex.getInstance().get(
-                property.symbol.callableId.asFqNameForDebugInfo().asString(),
+                property.symbol.callableId.asSingleFqName().asString(),
                 project,
                 property.scope(project)
             )

idea/idea-frontend-fir/src/org/jetbrains/kotlin/idea/frontend/api/fir/utils/shortenReferencesUtils.kt

@@ -24,7 +24,7 @@ fun addImportToFile(
     allUnder: Boolean = false,
     alias: Name? = null
 ) {
-    addImportToFile(project, file, callableId.asFqNameForDebugInfo(), allUnder, alias)
+    addImportToFile(project, file, callableId.asSingleFqName(), allUnder, alias)
 }
 
 /**

idea/src/org/jetbrains/kotlin/idea/quickfix/AddWhenRemainingBranchesFix.kt

@@ -100,7 +100,7 @@ class AddWhenRemainingBranchesFix(
                         } else {
                             "is "
                         } + case.classId.asSingleFqName().quoteIfNeeded().asString()
-                    is WhenMissingCase.EnumCheckIsMissing -> case.callableId.asFqNameForDebugInfo().quoteIfNeeded().asString()
+                    is WhenMissingCase.EnumCheckIsMissing -> case.callableId.asSingleFqName().quoteIfNeeded().asString()
                 }
                 val entry = psiFactory.createWhenEntry("$branchConditionText -> TODO()")
                 if (elseBranch != null) {