From b7b78c00586e5564e8927c43d8bd6a56d66b43d8 Mon Sep 17 00:00:00 2001
From: Yondon Fu <yondon.fu@gmail.com>
Date: Tue, 9 Jan 2018 12:42:33 -0500
Subject: [PATCH] internal/ethapi: add eth_nextNonce RPC method

---
 eth/bind.go            |  2 +-
 ethclient/ethclient.go |  2 +-
 internal/ethapi/api.go | 11 +++++++++++
 3 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/eth/bind.go b/eth/bind.go
index 769a6c741c..6e044716d6 100644
--- a/eth/bind.go
+++ b/eth/bind.go
@@ -104,7 +104,7 @@ func toBlockNumber(num *big.Int) rpc.BlockNumber {
 // PendingAccountNonce implements bind.ContractTransactor retrieving the current
 // pending nonce associated with an account.
 func (b *ContractBackend) PendingNonceAt(ctx context.Context, account common.Address) (nonce uint64, err error) {
-	out, err := b.txapi.GetTransactionCount(ctx, account, rpc.PendingBlockNumber)
+	out, err := b.txapi.NextNonce(ctx, account)
 	if out != nil {
 		nonce = uint64(*out)
 	}
diff --git a/ethclient/ethclient.go b/ethclient/ethclient.go
index 87a912901a..75db592b2c 100644
--- a/ethclient/ethclient.go
+++ b/ethclient/ethclient.go
@@ -400,7 +400,7 @@ func (ec *Client) PendingCodeAt(ctx context.Context, account common.Address) ([]
 // This is the nonce that should be used for the next transaction.
 func (ec *Client) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) {
 	var result hexutil.Uint64
-	err := ec.c.CallContext(ctx, &result, "eth_getTransactionCount", account, "pending")
+	err := ec.c.CallContext(ctx, &result, "eth_nextNonce", account)
 	return uint64(result), err
 }
 
diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go
index 55bd5aa1ba..575528ec25 100644
--- a/internal/ethapi/api.go
+++ b/internal/ethapi/api.go
@@ -971,6 +971,17 @@ func (s *PublicTransactionPoolAPI) GetTransactionCount(ctx context.Context, addr
 	return (*hexutil.Uint64)(&nonce), state.Error()
 }
 
+// NextNonce returns the next nonce for the given address taking into account any pending transactions the address has
+func (s *PublicTransactionPoolAPI) NextNonce(ctx context.Context, address common.Address) (*hexutil.Uint64, error) {
+	// Ask transaction pool for the nonce which includes pending transactions
+	nonce, err := s.b.GetPoolNonce(ctx, address)
+	if err != nil {
+		return nil, err
+	}
+
+	return (*hexutil.Uint64)(&nonce), nil
+}
+
 // GetTransactionByHash returns the transaction for the given hash
 func (s *PublicTransactionPoolAPI) GetTransactionByHash(ctx context.Context, hash common.Hash) *RPCTransaction {
 	// Try to return an already finalized transaction