From e745798a6ec04558291e72395dd0171051e1f459 Mon Sep 17 00:00:00 2001
From: Conner Fromknecht <conner@lightning.engineering>
Date: Tue, 17 Dec 2019 14:26:23 -0800
Subject: [PATCH] zpay32: update spec test vectors, write features last

This commit updates the BOLT11 test vectors to use the updated versions
from the spec (with TLV bit set). This also pointed out that the
ordering was inconsistent with the spec, in that the payment secret
should be serialized before the feature vector.
---
 zpay32/invoice.go      | 16 ++++++++--------
 zpay32/invoice_test.go | 21 +++++++++++++++------
 2 files changed, 23 insertions(+), 14 deletions(-)

diff --git a/zpay32/invoice.go b/zpay32/invoice.go
index 1677fa8d..b76924c0 100644
--- a/zpay32/invoice.go
+++ b/zpay32/invoice.go
@@ -1094,6 +1094,14 @@ func writeTaggedFields(bufferBase32 *bytes.Buffer, invoice *Invoice) error {
 			return err
 		}
 	}
+	if invoice.PaymentAddr != nil {
+		err := writeBytes32(
+			bufferBase32, fieldTypeS, *invoice.PaymentAddr,
+		)
+		if err != nil {
+			return err
+		}
+	}
 	if invoice.Features.SerializeSize32() > 0 {
 		var b bytes.Buffer
 		err := invoice.Features.RawFeatureVector.EncodeBase32(&b)
@@ -1106,14 +1114,6 @@ func writeTaggedFields(bufferBase32 *bytes.Buffer, invoice *Invoice) error {
 			return err
 		}
 	}
-	if invoice.PaymentAddr != nil {
-		err := writeBytes32(
-			bufferBase32, fieldTypeS, *invoice.PaymentAddr,
-		)
-		if err != nil {
-			return err
-		}
-	}
 
 	return nil
 }
diff --git a/zpay32/invoice_test.go b/zpay32/invoice_test.go
index 9a34b590..923e692e 100644
--- a/zpay32/invoice_test.go
+++ b/zpay32/invoice_test.go
@@ -42,6 +42,13 @@ var (
 		0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
 	}
 
+	specPaymentAddr = [32]byte{
+		0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+		0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+		0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+		0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11,
+	}
+
 	testEmptyString    = ""
 	testCupOfCoffee    = "1 cup coffee"
 	testCoffeeBeans    = "coffee beans"
@@ -499,8 +506,8 @@ func TestDecodeEncode(t *testing.T) {
 		},
 		{
 			// On mainnet, please send $30 coffee beans supporting
-			// features 1 and 9.
-			encodedInvoice: "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9qzsze992adudgku8p05pstl6zh7av6rx2f297pv89gu5q93a0hf3g7lynl3xq56t23dpvah6u7y9qey9lccrdml3gaqwc6nxsl5ktzm464sq73t7cl",
+			// features 9, 15 and 99, using secret 0x11...
+			encodedInvoice: "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdeessp5zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zygs9q5sqqqqqqqqqqqqqqqpqsq67gye39hfg3zd8rgc80k32tvy9xk2xunwm5lzexnvpx6fd77en8qaq424dxgt56cag2dpt359k3ssyhetktkpqh24jqnjyw6uqd08sgptq44qu",
 			valid:          true,
 			decodedInvoice: func() *Invoice {
 				return &Invoice{
@@ -508,10 +515,11 @@ func TestDecodeEncode(t *testing.T) {
 					MilliSat:    &testMillisat25mBTC,
 					Timestamp:   time.Unix(1496314658, 0),
 					PaymentHash: &testPaymentHash,
+					PaymentAddr: &specPaymentAddr,
 					Description: &testCoffeeBeans,
 					Destination: testPubKey,
 					Features: lnwire.NewFeatureVector(
-						lnwire.NewRawFeatureVector(1, 9),
+						lnwire.NewRawFeatureVector(9, 15, 99),
 						lnwire.Features,
 					),
 				}
@@ -525,8 +533,8 @@ func TestDecodeEncode(t *testing.T) {
 		},
 		{
 			// On mainnet, please send $30 coffee beans supporting
-			// features 1, 9, and 100.
-			encodedInvoice: "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdees9q4pqqqqqqqqqqqqqqqqqqszk3ed62snp73037h4py4gry05eltlp0uezm2w9ajnerhmxzhzhsu40g9mgyx5v3ad4aqwkmvyftzk4k9zenz90mhjcy9hcevc7r3lx2sphzfxz7",
+			// features 9, 15, 99, and 100, using secret 0x11...
+			encodedInvoice: "lnbc25m1pvjluezpp5qqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqqqsyqcyq5rqwzqfqypqdq5vdhkven9v5sxyetpdeessp5zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zyg3zygs9q4psqqqqqqqqqqqqqqqpqqqqu7fz6pjqczdm3jp3qps7xntj2w2mm70e0ckhw3c5xk9p36pvk3sewn7ncaex6uzfq0vtqzy28se6pcwn790vxex7xystzumhg55p6qq9wq7td",
 			valid:          false,
 			skipEncoding:   true,
 			decodedInvoice: func() *Invoice {
@@ -535,10 +543,11 @@ func TestDecodeEncode(t *testing.T) {
 					MilliSat:    &testMillisat25mBTC,
 					Timestamp:   time.Unix(1496314658, 0),
 					PaymentHash: &testPaymentHash,
+					PaymentAddr: &specPaymentAddr,
 					Description: &testCoffeeBeans,
 					Destination: testPubKey,
 					Features: lnwire.NewFeatureVector(
-						lnwire.NewRawFeatureVector(1, 9, 100),
+						lnwire.NewRawFeatureVector(9, 15, 99, 100),
 						lnwire.Features,
 					),
 				}