From 778a44dd64dd716e3bd398590cde4e7a9a3fe97a Mon Sep 17 00:00:00 2001
From: "Jamil Lambert, PhD" <Jamil.Lambert@proton.me>
Date: Thu, 13 Jun 2024 16:08:38 +0100
Subject: [PATCH] Refactor merkle block test

Refactored the unit test as suggested in
https://github.com/rust-bitcoin/rust-bitcoin/pull/2859#issuecomment-2161710169
---
 bitcoin/src/merkle_tree/block.rs | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

diff --git a/bitcoin/src/merkle_tree/block.rs b/bitcoin/src/merkle_tree/block.rs
index 438f0bfe1..7f93a6914 100644
--- a/bitcoin/src/merkle_tree/block.rs
+++ b/bitcoin/src/merkle_tree/block.rs
@@ -825,16 +825,25 @@ mod tests {
             1b01e32f570200000002252bf9d75c4f481ebb6278d708257d1f12beb6dd30301d26c623f789b2ba6fc0e2d3\
             2adb5f8ca820731dff234a84e78ec30bce4ec69dbd562d0b2b8266bf4e5a0105").unwrap();
         let mb: MerkleBlock = encode::deserialize(&mb_bytes).unwrap();
+
         // Authenticate and extract matched transaction ids
         let mut matches: Vec<Txid> = vec![];
         let mut index: Vec<u32> = vec![];
         assert!(mb.extract_matches(&mut matches, &mut index).is_ok());
-        assert_eq!(1, matches.len());
-        assert_eq!(
-            "5a4ebf66822b0b2d56bd9dc64ece0bc38ee7844a23ff1d7320a88c5fdb2ad3e2".parse::<Txid>().unwrap(),
-            matches[0]
-        );
-        assert_eq!(1, index.len());
-        assert_eq!(1, index[0]);
+
+        // The matches and index vectors are coupled, should be the same length.
+        assert_eq!(matches.len(), index.len());
+
+        // There should only be one match.
+        assert_eq!(matches.len(), 1);
+
+        // The match should come from index 1.
+        assert_eq!(index[0], 1);
+
+        // And we know the txid we want.
+        let want = "5a4ebf66822b0b2d56bd9dc64ece0bc38ee7844a23ff1d7320a88c5fdb2ad3e2"
+            .parse::<Txid>()
+            .expect("failed to parse txid");
+        assert_eq!(matches[0], want);
     }
 }