From d4a31d412732f03815a1e59575e9425ab0f4484a Mon Sep 17 00:00:00 2001
From: Tadge Dryja <tadge@lightning.network>
Date: Mon, 18 Jan 2016 20:43:02 -0800
Subject: [PATCH] add initial unit test for elkrem send / receive

---
 elkrem/elkrem_test.go | 69 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 elkrem/elkrem_test.go

diff --git a/elkrem/elkrem_test.go b/elkrem/elkrem_test.go
new file mode 100644
index 00000000..459a6dc6
--- /dev/null
+++ b/elkrem/elkrem_test.go
@@ -0,0 +1,69 @@
+package elkrem
+
+import (
+	"testing"
+
+	"github.com/btcsuite/btcd/wire"
+)
+
+// TestElkremBig makes a height 63 (max size possible) tree and tries 10K hashes
+func TestElkremBig(t *testing.T) {
+	ex := NewElkremSender(63, wire.DoubleSha256SH([]byte("elktest")))
+	rcv := NewElkremReceiver(63)
+	for n := uint64(0); n < 10000; n++ {
+		sha, err := ex.AtIndex(n)
+		if err != nil {
+			t.Fatal(err)
+		}
+		err = rcv.AddNext(sha)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if n%1000 == 999 {
+			t.Logf("stack with %d received hashes\n", n+1)
+			for i, n := range rcv.s {
+				t.Logf("Stack element %d: index %d height %d %s\n",
+					i, n.i, n.h, n.sha.String())
+			}
+		}
+	}
+	for n := uint64(0); n < 10000; n += 500 {
+		sha, err := rcv.AtIndex(n)
+		if err != nil {
+			t.Fatal(err)
+		}
+		t.Logf("Retreived index %d %s\n",
+			n, sha.String())
+	}
+}
+
+// TestElkremSmall makes a height 15 (65534 size) tree and tries 10K hashes
+func TestElkremSmall(t *testing.T) {
+	ex := NewElkremSender(15, wire.DoubleSha256SH([]byte("elktest")))
+	rcv := NewElkremReceiver(15)
+	for n := uint64(0); n < 5000; n++ {
+		sha, err := ex.AtIndex(n)
+		if err != nil {
+			t.Fatal(err)
+		}
+		err = rcv.AddNext(sha)
+		if err != nil {
+			t.Fatal(err)
+		}
+		if n%1000 == 999 {
+			t.Logf("stack with %d received hashes\n", n+1)
+			for i, n := range rcv.s {
+				t.Logf("Stack element %d: index %d height %d %s\n",
+					i, n.i, n.h, n.sha.String())
+			}
+		}
+	}
+	for n := uint64(0); n < 5000; n += 500 {
+		sha, err := rcv.AtIndex(n)
+		if err != nil {
+			t.Fatal(err)
+		}
+		t.Logf("Retreived index %d %s\n",
+			n, sha.String())
+	}
+}