diff --git a/platform/lang-impl/src/com/intellij/codeInsight/editorActions/ExtendWordSelectionHandlerBase.java b/platform/lang-impl/src/com/intellij/codeInsight/editorActions/ExtendWordSelectionHandlerBase.java
index 439f73c52a98..913552134ae5 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/editorActions/ExtendWordSelectionHandlerBase.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/editorActions/ExtendWordSelectionHandlerBase.java
@@ -20,6 +20,7 @@ import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.util.TextRange;
 import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.psi.PsiDocumentManager;
 import com.intellij.psi.PsiElement;
 import com.intellij.util.containers.ContainerUtil;
 import com.intellij.util.text.CharArrayUtil;
@@ -40,7 +41,14 @@ public abstract class ExtendWordSelectionHandlerBase implements ExtendWordSelect
   @Override
   public List<TextRange> select(PsiElement e, CharSequence editorText, int cursorOffset, Editor editor) {
     final TextRange originalRange = e.getTextRange();
-    LOG.assertTrue(originalRange.getEndOffset() <= editorText.length(), getClass() + "; " + e);
+    if (originalRange.getEndOffset() > editorText.length()) {
+      throw new AssertionError("Invalid element range in " + getClass() +
+                               "; element=" + e +
+                               "; range=" + originalRange +
+                               "; length=" + editorText +
+                               "; editor=" + editor +
+                               "; committed=" + PsiDocumentManager.getInstance(e.getProject()).isCommitted(editor.getDocument()));
+    }
 
     List<TextRange> ranges = expandToWholeLine(editorText, originalRange, true);
 
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordHandler.java b/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordHandler.java
index 7d0fa65e4ef4..8edbb3f5f11d 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordHandler.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordHandler.java
@@ -149,6 +149,10 @@ public class SelectWordHandler extends EditorActionHandler {
       }
     }
 
+    if (element != null && element.getTextRange().getEndOffset() > editor.getDocument().getTextLength()) {
+      throw new AssertionError("Wrong element range " + element + "; committed=" + PsiDocumentManager.getInstance(project).isCommitted(document));
+    }
+
     final TextRange selectionRange = new TextRange(editor.getSelectionModel().getSelectionStart(), editor.getSelectionModel().getSelectionEnd());
 
     final Ref<TextRange> minimumRange = new Ref<TextRange>(new TextRange(0, editor.getDocument().getTextLength()));
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordUtil.java b/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordUtil.java
index 8253873421fe..94d59648de61 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordUtil.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/editorActions/SelectWordUtil.java
@@ -218,8 +218,12 @@ public class SelectWordUtil {
         availableSelectioners.add(selectioner);
       }
     }
+    long stamp = editor.getDocument().getModificationStamp();
     for (ExtendWordSelectionHandler selectioner : availableSelectioners) {
       List<TextRange> ranges = selectioner.select(element, text, cursorOffset, editor);
+      if (stamp != editor.getDocument().getModificationStamp()) {
+        throw new AssertionError("Selectioner " + selectioner + " has changed the document");
+      }
       if (ranges == null) continue;
 
       for (TextRange range : ranges) {