diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/AbstractMappingStrategy.java b/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/AbstractMappingStrategy.java
index 3feff609a59c..2eef57fc2ef5 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/AbstractMappingStrategy.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/AbstractMappingStrategy.java
@@ -171,7 +171,7 @@ abstract class AbstractMappingStrategy<T> implements MappingStrategy<T> {
         collapsedSymbolsWidthInColumns = foldingData.getCollapsedSymbolsWidthInColumns();
       }
       else {
-        assert false;
+        assert false : String.format("Problem fold region: %s. Soft wraps cache: %s", foldRegion, myCache);
       }
     }
     else {
diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/CacheEntry.java b/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/CacheEntry.java
index 4c0d8590905b..8d687a168bf5 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/CacheEntry.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/impl/softwrap/mapping/CacheEntry.java
@@ -26,6 +26,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 
@@ -218,7 +219,8 @@ class CacheEntry implements Comparable<CacheEntry>, Cloneable {
 
   @Override
   public String toString() {
-    return "visual line: " + visualLine + ", offsets: " + startOffset + "-" + endOffset;
+    return "visual line: " + visualLine + ", offsets: " + startOffset + "-" + endOffset + ", fold regions: " 
+           + Arrays.toString(myFoldingData.getValues());
   }
 
   @Override