From f5097625fc948d6395d4a5127cda7cee021a6aeb Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Fri, 17 Jul 2015 13:27:40 +0200
Subject: [PATCH] avoid expensive LookupElement.isValid check on every repaint,
 just ignore invalid frozen items (EA-68259 - PIEAE: PsiUtilCore.ensureValid)

---
 .../codeInsight/completion/CompletionLookupArranger.java | 7 ++++++-
 .../com/intellij/codeInsight/lookup/LookupArranger.java  | 9 +--------
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java b/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java
index cb4ae3924c4d..c98aaf342115 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/completion/CompletionLookupArranger.java
@@ -256,7 +256,12 @@ public class CompletionLookupArranger extends LookupArranger {
   }
 
   private void addFrozenItems(Set<LookupElement> items, LinkedHashSet<LookupElement> model) {
-    myFrozenItems.retainAll(items);
+    for (Iterator<LookupElement> iterator = myFrozenItems.iterator(); iterator.hasNext(); ) {
+      LookupElement element = iterator.next();
+      if (!element.isValid() || !items.contains(element)) {
+        iterator.remove();
+      }
+    }
     model.addAll(myFrozenItems);
   }
 
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/lookup/LookupArranger.java b/platform/lang-impl/src/com/intellij/codeInsight/lookup/LookupArranger.java
index 7ea82fba16d0..6342f0e2c55e 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/lookup/LookupArranger.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/lookup/LookupArranger.java
@@ -20,9 +20,7 @@ import com.intellij.codeInsight.completion.PrefixMatcher;
 import com.intellij.codeInsight.completion.impl.CompletionServiceImpl;
 import com.intellij.codeInsight.lookup.impl.LookupImpl;
 import com.intellij.openapi.util.Comparing;
-import com.intellij.openapi.util.Condition;
 import com.intellij.openapi.util.Pair;
-import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.*;
@@ -104,12 +102,7 @@ public abstract class LookupArranger {
   }
 
   protected List<LookupElement> getMatchingItems() {
-    return ContainerUtil.filter(myMatchingItems, new Condition<LookupElement>() {
-      @Override
-      public boolean value(LookupElement element) {
-        return element.isValid();
-      }
-    });
+    return myMatchingItems;
   }
 
   public Map<LookupElement,StringBuilder> getRelevanceStrings() {