From 815f38e1d71ab4b339b30b3b535b9d8bffd28998 Mon Sep 17 00:00:00 2001
From: chadlagore <chad.d.lagore@gmail.com>
Date: Tue, 25 Jul 2017 22:57:41 -0700
Subject: [PATCH] handle double spend within pool

---
 pool/pool.go      |  5 +++++
 pool/pool_test.go | 11 +++++++++++
 2 files changed, 16 insertions(+)

diff --git a/pool/pool.go b/pool/pool.go
index 66129b6..6ba7ac9 100644
--- a/pool/pool.go
+++ b/pool/pool.go
@@ -86,7 +86,12 @@ func (p *Pool) SetUnsafe(t *blockchain.Transaction) {
 }
 
 // Silently adds a transaction to the pool.
+// Deletes a transaction if it exists from the same
+// input hash.
 func (p *Pool) set(t *blockchain.Transaction) {
+	if txn, ok := p.ValidTransactions[t.Input.Hash]; ok {
+		p.Delete(txn.Transaction)
+	}
 	vt := &PooledTransaction{
 		Transaction: t,
 		Time:        time.Now(),
diff --git a/pool/pool_test.go b/pool/pool_test.go
index 6710deb..5a9740f 100644
--- a/pool/pool_test.go
+++ b/pool/pool_test.go
@@ -121,3 +121,14 @@ func TestPop(t *testing.T) {
 	p := New()
 	assert.Nil(t, p.Pop())
 }
+
+func TestSetDedupes(t *testing.T) {
+	p := New()
+	t1 := blockchain.NewTestTransaction()
+	t2 := blockchain.NewTestTransaction()
+	t1.Input.Hash = t2.Input.Hash
+	p.SetUnsafe(t1)
+	p.SetUnsafe(t2)
+	assert.Equal(t, p.Peek(), t2)
+	assert.Equal(t, p.Len(), 1)
+}