Merge pull request #69 from bladehan1/fix-check-empty

add(txpool): add check for empty lists in txpool

core/tx_list.go

@@ -240,6 +240,10 @@ func (m *txSortedMap) Flatten() types.Transactions {
 // transaction with the highest nonce
 func (m *txSortedMap) LastElement() *types.Transaction {
 	cache := m.flatten()
+	ln := len(cache)
+	if ln == 0 {
+		return nil
+	}
 	return cache[len(cache)-1]
 }
 

core/tx_pool.go

@@ -1256,6 +1256,9 @@ func (pool *TxPool) runReorg(done chan struct{}, reset *txpoolResetRequest, dirt
 	// Update all accounts to the latest known pending nonce
 	for addr, list := range pool.pending {
 		highestPending := list.LastElement()
+		if highestPending == nil {
+			continue
+		}
 		pool.pendingNonces.set(addr, highestPending.Nonce()+1)
 	}
 	dropBetweenReorgHistogram.Update(int64(pool.changesSinceReorg))