diff --git a/platform/lang-impl/src/com/intellij/psi/stubs/StubIndexImpl.java b/platform/lang-impl/src/com/intellij/psi/stubs/StubIndexImpl.java
index 3cd61172d534..22cbcbe9fab5 100644
--- a/platform/lang-impl/src/com/intellij/psi/stubs/StubIndexImpl.java
+++ b/platform/lang-impl/src/com/intellij/psi/stubs/StubIndexImpl.java
@@ -52,7 +52,6 @@ import java.util.concurrent.atomic.AtomicReference;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReadWriteLock;
 import java.util.function.IntPredicate;
-import java.util.stream.Collectors;
 
 @State(name = "FileBasedIndex", storages = {
   @Storage(value = StoragePathMacros.CACHE_FILE),
@@ -197,13 +196,14 @@ public final class StubIndexImpl extends StubIndexEx implements PersistentStateC
         UpdatableIndex<K, Void, FileContent> index = new VfsAwareMapReduceIndex<>(wrappedExtension, memStorage, null, null, null, lock);
 
         if (stubUpdatingIndex instanceof MergedInvertedIndex) {
-          List<ProvidedIndexExtension<K, Void>> providedIndexExtensions = ((MergedInvertedIndex<Integer, SerializedStubTree>)stubUpdatingIndex)
-                  .getProvidedExtensions()
-                  .filter(ex -> ex instanceof StubProvidedIndexExtension)
-                  .map(ex -> ((StubProvidedIndexExtension)ex).findProvidedStubIndex(extension))
-                  .collect(Collectors.toList());
-          if (!providedIndexExtensions.isEmpty()) {
-            index = ProvidedIndexExtension.wrapWithProvidedIndex(providedIndexExtensions, wrappedExtension, index, ((MergedInvertedIndex<Integer, SerializedStubTree>)stubUpdatingIndex).getHashIndex());
+          ProvidedIndexExtension<Integer, SerializedStubTree> ex =
+            ((MergedInvertedIndex<Integer, SerializedStubTree>)stubUpdatingIndex).getProvidedExtension();
+          if (ex instanceof StubProvidedIndexExtension) {
+            ProvidedIndexExtension<K, Void> providedStubIndexExtension =
+              ((StubProvidedIndexExtension)ex).findProvidedStubIndex(extension);
+            if (providedStubIndexExtension != null) {
+              index = ProvidedIndexExtension.wrapWithProvidedIndex(providedStubIndexExtension, wrappedExtension, index);
+            }
           }
         }