Fixed bug where elements which are read in a transaction end up with …

…incorrect usedInTransaction counts which may trigger unintended TransactionExceptions

tinkergraph-gremlin/src/main/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/TinkerElementContainer.java

@@ -197,7 +197,7 @@ public void commit(final long txVersion) {
                 element.removed = true;
             element = null;
             isDeleted = true;
-        } else {
+        } else if (isModifiedInTx.get()){
             element = transactionUpdatedValue.get();
             element.currentVersion = txVersion;
         }

tinkergraph-gremlin/src/main/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/TinkerTransaction.java

@@ -203,7 +203,7 @@ protected void doCommit() throws TransactionException {
 
             final Set<TinkerElementContainer> readElements = txReadElements.get();
             if (readElements != null)
-                readElements.stream().forEach(e -> e.reset());
+                readElements.stream().forEach(e -> e.commit(txVersion));
 
             txChangedVertices.remove();
             txChangedEdges.remove();

tinkergraph-gremlin/src/test/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/TinkerTransactionGraphTest.java

@@ -1457,4 +1457,24 @@ public void shouldHandleAddingVertexWhenOtherTxTryToDeleteSameVertex() throws In
 
         countElementsInNewThreadTx(g, 1, 0);
     }
+
+    @Test
+    public void shouldHandleSequenceOfCreateReadDeleteCreateSameVertex() {
+        final TinkerTransactionGraph graph = TinkerTransactionGraph.open();
+        final GraphTraversalSource g = graph.traversal();
+
+        g.addV().property(T.id, 1).next();
+        graph.tx().commit();
+        g.V().next();
+        graph.tx().commit();
+        g.V().drop().iterate();
+        graph.tx().commit();
+
+        assertEquals(false, graph.hasVertex(1));
+
+        g.addV().property(T.id, 1).next();
+        graph.tx().commit();
+
+        assertEquals(true, graph.hasVertex(1));
+    }
 }