From 7448cdc154e07b8e7c2ad4f6a8022c2088cd80a9 Mon Sep 17 00:00:00 2001
From: Jae Kwon <jae@tendermint.com>
Date: Mon, 30 Nov 2015 15:22:42 -0800
Subject: [PATCH] Add serial=on option for CounterApplication

---
 example/counter.go | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/example/counter.go b/example/counter.go
index 6e6b6527a..870d5a808 100644
--- a/example/counter.go
+++ b/example/counter.go
@@ -35,6 +35,7 @@ type CounterAppContext struct {
 	hashCount   int
 	txCount     int
 	commitCount int
+	serial      bool
 }
 
 func (appC *CounterAppContext) Echo(message string) string {
@@ -46,10 +47,22 @@ func (appC *CounterAppContext) Info() []string {
 }
 
 func (appC *CounterAppContext) SetOption(key string, value string) types.RetCode {
+	if key == "serial" && value == "on" {
+		appC.serial = true
+	}
 	return 0
 }
 
 func (appC *CounterAppContext) AppendTx(tx []byte) ([]types.Event, types.RetCode) {
+	if appC.serial {
+		txValue, bz := binary.Varint(tx)
+		if bz <= 0 {
+			return nil, types.RetCodeInternalError
+		}
+		if txValue != int64(appC.txCount) {
+			return nil, types.RetCodeInternalError
+		}
+	}
 	appC.txCount += 1
 	return nil, 0
 }