From c11d9ccfc47223a09189a5c447339966708658d5 Mon Sep 17 00:00:00 2001
From: peter <peter@jetbrains.com>
Date: Fri, 4 Aug 2017 14:56:48 +0200
Subject: [PATCH] diagnostics for null in goto popup model (EA-104872 - assert:
 Diff.buildChanges)

---
 .../intellij/ide/util/gotoByName/ChooseByNameBase.java    | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/platform/lang-impl/src/com/intellij/ide/util/gotoByName/ChooseByNameBase.java b/platform/lang-impl/src/com/intellij/ide/util/gotoByName/ChooseByNameBase.java
index 77d349da02e6..86f914059cd1 100644
--- a/platform/lang-impl/src/com/intellij/ide/util/gotoByName/ChooseByNameBase.java
+++ b/platform/lang-impl/src/com/intellij/ide/util/gotoByName/ChooseByNameBase.java
@@ -75,6 +75,7 @@ import com.intellij.usageView.UsageInfo;
 import com.intellij.usages.*;
 import com.intellij.usages.impl.UsageViewManagerImpl;
 import com.intellij.util.Alarm;
+import com.intellij.util.ArrayUtil;
 import com.intellij.util.Consumer;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.indexing.FileBasedIndex;
@@ -983,6 +984,9 @@ public abstract class ChooseByNameBase {
 
     Object[] oldElements = myListModel.getItems().toArray();
     Object[] newElements = elements.toArray();
+    if (ArrayUtil.contains(null, newElements)) {
+      LOG.error("Null after filtering elements by " + this);
+    }
     List<ModelDiff.Cmd> commands = ModelDiff.createDiffCmds(myListModel, oldElements, newElements);
 
     myTextField.setForeground(UIUtil.getTextFieldForeground());
@@ -1451,6 +1455,10 @@ public abstract class ChooseByNameBase {
         indicator,
         o -> {
           if (indicator.isCanceled()) return false;
+          if (o == null) {
+            LOG.error("Null returned from " + myProvider + " with " + myModel + " in " + ChooseByNameBase.this);
+            return true;
+          }
           elements.add(o);
 
           if (isOverflow(elements)) {