diff --git a/plugins/kotlin/base/fe10/analysis/src/org/jetbrains/kotlin/idea/decompiler/navigation/SourceNavigationHelper.kt b/plugins/kotlin/base/fe10/analysis/src/org/jetbrains/kotlin/idea/decompiler/navigation/SourceNavigationHelper.kt
index 02b6cbe4bca3..045ab330e524 100644
--- a/plugins/kotlin/base/fe10/analysis/src/org/jetbrains/kotlin/idea/decompiler/navigation/SourceNavigationHelper.kt
+++ b/plugins/kotlin/base/fe10/analysis/src/org/jetbrains/kotlin/idea/decompiler/navigation/SourceNavigationHelper.kt
@@ -135,7 +135,7 @@ object SourceNavigationHelper {
     private fun Collection<GlobalSearchScope>.union(): List<GlobalSearchScope> =
         if (this.isNotEmpty()) listOf(GlobalSearchScope.union(this)) else emptyList()
 
-    private fun haveRenamesInImports(files: Collection<KtFile>) = files.any { file -> file.importDirectives.any { it.aliasName != null } }
+    private fun haveRenamesInImports(files: Collection<KtFile>) = files.any(KtFile::hasImportAlias)
 
     private fun findSpecialProperty(memberName: Name, containingClass: KtClass): KtNamedDeclaration? {
         // property constructor parameters
diff --git a/plugins/kotlin/base/psi/src/org/jetbrains/kotlin/idea/base/psi/KotlinPsiHeuristics.kt b/plugins/kotlin/base/psi/src/org/jetbrains/kotlin/idea/base/psi/KotlinPsiHeuristics.kt
index afe1113d221d..7692cb17bf08 100644
--- a/plugins/kotlin/base/psi/src/org/jetbrains/kotlin/idea/base/psi/KotlinPsiHeuristics.kt
+++ b/plugins/kotlin/base/psi/src/org/jetbrains/kotlin/idea/base/psi/KotlinPsiHeuristics.kt
@@ -23,6 +23,8 @@ import org.jetbrains.kotlin.utils.addToStdlib.safeAs
 object KotlinPsiHeuristics {
     @JvmStatic
     fun unwrapImportAlias(file: KtFile, aliasName: String): Collection<String> {
+        if (!file.hasImportAlias()) return emptyList()
+
         return file.aliasImportMap[aliasName]
     }
 
@@ -34,6 +36,8 @@ object KotlinPsiHeuristics {
 
     @JvmStatic
     fun getImportAliases(file: KtFile, names: Set<String>): Set<String> {
+        if (!file.hasImportAlias()) return emptySet()
+
         val result = LinkedHashSet<String>()
         for ((aliasName, name) in file.aliasImportMap.entries()) {
             if (name in names) {
@@ -71,6 +75,7 @@ object KotlinPsiHeuristics {
         val file = type.containingKotlinFileStub?.psi as? KtFile ?: return false
 
         // TODO: support type aliases
+        if (!file.hasImportAlias()) return false
         return file.aliasImportMap[referencedName].contains("Nothing")
     }
 
diff --git a/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/imports/KotlinImportOptimizer.kt b/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/imports/KotlinImportOptimizer.kt
index 2ece327bbd0d..2ad6fa7bdfb6 100644
--- a/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/imports/KotlinImportOptimizer.kt
+++ b/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/imports/KotlinImportOptimizer.kt
@@ -97,11 +97,15 @@ class KotlinImportOptimizer : ImportOptimizer {
 
     private class CollectUsedDescriptorsVisitor(file: KtFile) : KtVisitorVoid() {
         private val currentPackageName = file.packageFqName
-        private val aliases: Map<FqName, List<Name>> = file.importDirectives
-            .asSequence()
-            .filter { !it.isAllUnder && it.alias != null }
-            .mapNotNull { it.importPath }
-            .groupBy(keySelector = { it.fqName }, valueTransform = { it.importedName as Name })
+        private val aliases: Map<FqName, List<Name>> = if (file.hasImportAlias()) {
+            file.importDirectives
+              .asSequence()
+              .filter { !it.isAllUnder && it.alias != null }
+              .mapNotNull { it.importPath }
+              .groupBy(keySelector = { it.fqName }, valueTransform = { it.importedName as Name })
+        } else {
+            emptyMap()
+        }
 
         private val descriptorsToImport = hashSetOf<OptimizedImportsBuilder.ImportableDescriptor>()
         private val namesToImport = hashMapOf<FqName, MutableSet<Name>>()
diff --git a/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/inspections/ReplaceWithImportAliasInspection.kt b/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/inspections/ReplaceWithImportAliasInspection.kt
index eef574ecc446..81500e9c8e1d 100644
--- a/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/inspections/ReplaceWithImportAliasInspection.kt
+++ b/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/inspections/ReplaceWithImportAliasInspection.kt
@@ -35,7 +35,10 @@ class ReplaceWithImportAliasInspection : AbstractKotlinInspection() {
 
     private fun KtNameReferenceExpression.aliasNameIdentifier(): PsiElement? {
         val name = getIdentifier()?.text ?: return null
-        val imports = containingKtFile.importDirectives.filter {
+        val ktFile = containingKtFile
+        if (!ktFile.hasImportAlias()) return null
+
+        val imports = ktFile.importDirectives.filter {
             !it.isAllUnder && it.alias != null && it.importedFqName?.shortName()?.asString() == name
         }.ifEmpty { return null }
 
diff --git a/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/intentions/AddFullQualifierIntention.kt b/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/intentions/AddFullQualifierIntention.kt
index efb2c9356b29..32cfd4b00a5e 100644
--- a/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/intentions/AddFullQualifierIntention.kt
+++ b/plugins/kotlin/idea/src/org/jetbrains/kotlin/idea/intentions/AddFullQualifierIntention.kt
@@ -61,7 +61,7 @@ class AddFullQualifierIntention : SelfTargetingIntention<KtNameReferenceExpressi
             val file = referenceExpression.containingKtFile
             val identifier = referenceExpression.getIdentifier()?.text
             val fqName = resultDescriptor.importableFqName
-            return !file.importDirectives.any { it.aliasName == identifier && it.importedFqName == fqName }
+            return !file.hasImportAlias() || file.importDirectives.none { it.aliasName == identifier && it.importedFqName == fqName }
         }
 
         fun applyTo(referenceExpression: KtNameReferenceExpression, fqName: FqName): KtElement {