Fixed invalid traversal optimization if vertex is not existing but filter would let null pass

arangod/V8Server/V8Traverser.cpp

@@ -777,8 +777,14 @@ Json* SingleServerTraversalPath::vertexToJson (Transaction* trx,
     }
   }
   TRI_doc_mptr_copy_t mptr;
-  trx->readSingle(collection, &mptr, v.key);
+  int res = trx->readSingle(collection, &mptr, v.key);
   ++_readDocuments;
+  if (res != TRI_ERROR_NO_ERROR) {
+    if (res == TRI_ERROR_ARANGO_DOCUMENT_NOT_FOUND) {
+      return new Json(Json::Null);
+    }
+    THROW_ARANGO_EXCEPTION(res);
+  }
   return new Json(TRI_ExpandShapedJson(
     collection->_collection->_collection->getShaper(),
     resolver,
@@ -849,8 +855,22 @@ bool DepthFirstTraverser::vertexMatchesConditions (VertexId const& v, size_t dep
          int res = _trx->readSingle(collection, &mptr, v.key); 
           ++_readDocuments;
           if (res != TRI_ERROR_NO_ERROR) {
-            // Vertex does not exist. Do not try filter
+            if (res == TRI_ERROR_ARANGO_DOCUMENT_NOT_FOUND) {
-            return false;
+              // Vertex does not exist. Do not try filter
+              triagens::basics::Json tmp(triagens::basics::Json::Null);
+              // This needs a different check method now.
+              // Innerloop here
+              for (auto const& exp2 : it->second) {
+                if (! exp2->isEdgeAccess) {
+                  if (! exp2->matchesCheck(tmp.json())) {
+                    ++_filteredPaths;
+                    return false;
+                  }
+                }
+              }
+              return true;
+            }
+            THROW_ARANGO_EXCEPTION(res);
           }
           docCol = collection->_collection->_collection;
         }

arangod/VocBase/Traverser.cpp

@@ -30,7 +30,6 @@
 #include "Traverser.h"
 #include "Basics/json-utilities.h"
 #include "VocBase/KeyGenerator.h"
-#include <iostream>
 
 using TraverserExpression = triagens::arango::traverser::TraverserExpression;
 
@@ -153,11 +152,11 @@ bool TraverserExpression::recursiveCheck (triagens::aql::AstNode const* node,
 ////////////////////////////////////////////////////////////////////////////////
 
 bool TraverserExpression::matchesCheck (DocumentAccessor& accessor) const {
-  if (! recursiveCheck(varAccess, accessor)) {
-    return false;
-  }
 
-  triagens::basics::Json result = accessor.toJson();
+  triagens::basics::Json result(triagens::basics::Json::Null);
+  if (recursiveCheck(varAccess, accessor)) {
+    result = accessor.toJson();
+  }
 
   TRI_ASSERT(compareTo != nullptr);
   TRI_ASSERT(compareTo->json() != nullptr);