The p/c queries must always be wrapped in a CustomQueryWrappingFilter in fquery parser.

Also made assertions more descriptive when failing.

src/main/java/org/elasticsearch/index/query/QueryFilterParser.java

@@ -23,6 +23,7 @@ import org.apache.lucene.search.Filter;
 import org.apache.lucene.search.Query;
 import org.apache.lucene.search.QueryWrapperFilter;
 import org.elasticsearch.common.inject.Inject;
+import org.elasticsearch.index.search.child.CustomQueryWrappingFilter;
 
 import java.io.IOException;
 
@@ -48,6 +49,10 @@ public class QueryFilterParser implements FilterParser {
         if (query == null) {
             return null;
         }
-        return new QueryWrapperFilter(query);
+        if (CustomQueryWrappingFilter.shouldUseCustomQueryWrappingFilter(query)) {
+            return new CustomQueryWrappingFilter(query);
+        } else {
+            return new QueryWrapperFilter(query);
+        }
     }
 }

src/main/java/org/elasticsearch/index/search/child/ChildrenConstantScoreQuery.java

@@ -95,7 +95,7 @@ public class ChildrenConstantScoreQuery extends Query {
         if (rewrittenChildQuery == null) {
             childQuery = rewrittenChildQuery = searcher.rewrite(originalChildQuery);
         } else {
-            assert rewriteIndexReader == searcher.getIndexReader();
+            assert rewriteIndexReader == searcher.getIndexReader()  : "not equal, rewriteIndexReader=" + rewriteIndexReader + " searcher.getIndexReader()=" + searcher.getIndexReader();
             childQuery = rewrittenChildQuery;
         }
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());

src/main/java/org/elasticsearch/index/search/child/ChildrenQuery.java

@@ -142,7 +142,7 @@ public class ChildrenQuery extends Query {
         if (rewrittenChildQuery == null) {
             childQuery = rewrittenChildQuery = searcher.rewrite(originalChildQuery);
         } else {
-            assert rewriteIndexReader == searcher.getIndexReader();
+            assert rewriteIndexReader == searcher.getIndexReader() : "not equal, rewriteIndexReader=" + rewriteIndexReader + " searcher.getIndexReader()=" + searcher.getIndexReader();
             childQuery = rewrittenChildQuery;
         }
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());

src/main/java/org/elasticsearch/index/search/child/CustomQueryWrappingFilter.java

@@ -121,4 +121,15 @@ public class CustomQueryWrappingFilter extends NoCacheFilter implements Releasab
     public int hashCode() {
         return query.hashCode() ^ 0x823D64C9;
     }
+
+    /** @return Whether {@link CustomQueryWrappingFilter} should be used. */
+    public static boolean shouldUseCustomQueryWrappingFilter(Query query) {
+        if (query instanceof TopChildrenQuery || query instanceof ChildrenConstantScoreQuery
+                || query instanceof ChildrenQuery || query instanceof ParentConstantScoreQuery
+                || query instanceof ParentQuery) {
+            return true;
+        } else {
+            return false;
+        }
+    }
 }

src/main/java/org/elasticsearch/index/search/child/ParentConstantScoreQuery.java

@@ -85,7 +85,7 @@ public class ParentConstantScoreQuery extends Query {
         if (rewrittenParentQuery != null) {
             parentQuery = rewrittenParentQuery;
         } else {
-            assert rewriteIndexReader == searcher.getIndexReader();
+            assert rewriteIndexReader == searcher.getIndexReader() : "not equal, rewriteIndexReader=" + rewriteIndexReader + " searcher.getIndexReader()=" + searcher.getIndexReader();
             parentQuery = rewrittenParentQuery = originalParentQuery.rewrite(searcher.getIndexReader());
         }
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());

src/main/java/org/elasticsearch/index/search/child/ParentQuery.java

@@ -129,7 +129,7 @@ public class ParentQuery extends Query {
         if (rewrittenParentQuery == null) {
             parentQuery = rewrittenParentQuery = searcher.rewrite(originalParentQuery);
         } else {
-            assert rewriteIndexReader == searcher.getIndexReader();
+            assert rewriteIndexReader == searcher.getIndexReader() : "not equal, rewriteIndexReader=" + rewriteIndexReader + " searcher.getIndexReader()=" + searcher.getIndexReader();
             parentQuery = rewrittenParentQuery;
         }
         IndexSearcher indexSearcher = new IndexSearcher(searcher.getIndexReader());