diff --git a/platform/testFramework/src/com/intellij/testFramework/PlatformTestCase.java b/platform/testFramework/src/com/intellij/testFramework/PlatformTestCase.java
index 756a9593decd..401bc0b4b17e 100644
--- a/platform/testFramework/src/com/intellij/testFramework/PlatformTestCase.java
+++ b/platform/testFramework/src/com/intellij/testFramework/PlatformTestCase.java
@@ -74,6 +74,7 @@ import com.intellij.util.indexing.FileBasedIndex;
 import com.intellij.util.indexing.FileBasedIndexImpl;
 import com.intellij.util.indexing.IndexableSetContributor;
 import com.intellij.util.ui.UIUtil;
+import gnu.trove.THashSet;
 import junit.framework.TestCase;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.NotNull;
@@ -104,7 +105,7 @@ public abstract class PlatformTestCase extends UsefulTestCase implements DataPro
   protected ProjectManagerEx myProjectManager;
   protected Project myProject;
   protected Module myModule;
-  protected static final Collection<File> myFilesToDelete = new HashSet<>();
+  protected static final Collection<File> myFilesToDelete = new THashSet<>();
   protected boolean myAssertionsInTestDetected;
   protected static final Logger LOG = Logger.getInstance("#com.intellij.testFramework.PlatformTestCase");
   public static Thread ourTestThread;