From 82ac2c6a311c2b54333b90ecd672792c44442a7f Mon Sep 17 00:00:00 2001
From: optout <13562139+optout21@users.noreply.github.com>
Date: Thu, 29 Aug 2024 17:44:43 +0200
Subject: [PATCH] Add [u8; N] impl, more tests

---
 lightning-invoice/src/de.rs          |  8 ++++++++
 lightning-invoice/src/test_ser_de.rs | 29 ++++++++++++++++++++++++++--
 2 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/lightning-invoice/src/de.rs b/lightning-invoice/src/de.rs
index 3330e490d20..d5ff0cc93a4 100644
--- a/lightning-invoice/src/de.rs
+++ b/lightning-invoice/src/de.rs
@@ -46,6 +46,14 @@ impl FromBase32 for Vec<u8> {
 	}
 }
 
+impl<const N: usize> FromBase32 for [u8; N] {
+	type Err = CheckedHrpstringError;
+
+	fn from_base32(data: &[Fe32]) -> Result<Self, Self::Err> {
+		Ok(data.iter().copied().fes_to_bytes().collect::<Vec<_>>().try_into().unwrap())
+	}
+}
+
 impl FromBase32 for PaymentSecret {
 	type Err = CheckedHrpstringError;
 
diff --git a/lightning-invoice/src/test_ser_de.rs b/lightning-invoice/src/test_ser_de.rs
index dac9b1495f9..643ad89b78d 100644
--- a/lightning-invoice/src/test_ser_de.rs
+++ b/lightning-invoice/src/test_ser_de.rs
@@ -48,6 +48,15 @@ fn vec_u8() {
 	ser_de_test_len(vec![255, 254, 253, 252, 251, 250, 249, 248, 247, 246], "lll0ml8mltul3alk");
 }
 
+#[test]
+fn array_u8() {
+	ser_de_test_len([0], "qq");
+	ser_de_test_len([255], "lu");
+	ser_de_test_len([0, 1], "qqqs");
+	ser_de_test_len([0, 1, 2, 3, 4, 5, 6, 7, 8, 9], "qqqsyqcyq5rqwzqf");
+	ser_de_test_len([255, 254, 253, 252, 251, 250, 249, 248, 247, 246], "lll0ml8mltul3alk");
+}
+
 #[test]
 fn payment_secret() {
 	let payment_secret = PaymentSecret([7; 32]);
@@ -66,8 +75,24 @@ fn positive_timestamp() {
 fn bolt11_invoice_features() {
 	use crate::Bolt11InvoiceFeatures;
 
-	let features = Bolt11InvoiceFeatures::from_le_bytes(vec![1, 2, 3, 4, 5, 42, 100, 101]);
-	ser_de_test_len(features, "x2ep2q5zqxqsp");
+	// Test few values, lengths, and paddings
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1, 2, 3, 4, 5, 42, 100, 101]), "x2ep2q5zqxqsp");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![]), "");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![0]), "");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1]), "p");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![31]), "l");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![100]), "ry");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![255]), "8l");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1]), "p");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1, 2]), "sp");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1, 2, 3]), "xqsp");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1, 2, 3, 4]), "zqxqsp");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![1, 2, 3, 4, 5]), "5zqxqsp");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![255, 254, 253, 252, 251]), "l070mlhl");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![100, 0]), "ry");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![100, 0, 0, 0]), "ry");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![0, 100]), "eqq");
+	ser_de_test_len(Bolt11InvoiceFeatures::from_le_bytes(vec![0, 0, 0, 100]), "pjqqqqq");
 }
 
 #[test]