From a5fc82e2b1403b7bf0f1ad494a62ccff793f99d0 Mon Sep 17 00:00:00 2001
From: ViniciusCestarii <viniciuscestari01@gmail.com>
Date: Tue, 25 Aug 2026 09:18:59 -0300
Subject: [PATCH] test: cover enforce BIP68 to tx versions higher than 2

---
 src/test/transaction_tests.cpp | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/src/test/transaction_tests.cpp b/src/test/transaction_tests.cpp
index 7caacab9488..beb0e740927 100644
--- a/src/test/transaction_tests.cpp
+++ b/src/test/transaction_tests.cpp
@@ -6,6 +6,7 @@
 #include <test/data/tx_valid.json.h>
 #include <test/util/setup_common.h>
 
+#include <chain.h>
 #include <checkqueue.h>
 #include <clientversion.h>
 #include <consensus/amount.h>
@@ -1190,6 +1191,30 @@ BOOST_AUTO_TEST_CASE(isfinaltx_sequences_test)
     check_final(/*sequences=*/{CTxIn::MAX_SEQUENCE_NONFINAL, CTxIn::SEQUENCE_FINAL}, /*expected_final=*/false);
 }
 
+BOOST_AUTO_TEST_CASE(calculatesequencelocks_tx_version_test)
+{
+    constexpr int coin_height{100};
+
+    // A single input with a height-based relative locktime of one block. Only the
+    // height branch is taken, so the block index is never dereferenced.
+    auto check_min_height{[](uint32_t version, int expected_min_height) {
+        CMutableTransaction mtx;
+        mtx.version = version;
+        mtx.vin.emplace_back(COutPoint{}, CScript{}, /*nSequenceIn=*/1);
+
+        std::vector<int> prev_heights{coin_height};
+        const CBlockIndex block{};
+        const auto lock_pair{CalculateSequenceLocks(CTransaction{mtx}, LOCKTIME_VERIFY_SEQUENCE, prev_heights, block)};
+        BOOST_CHECK_EQUAL(lock_pair.first, expected_min_height);
+    }};
+
+    // BIP68 only applies to versions 2 and up
+    check_min_height(/*version=*/0, /*expected_min_height=*/-1);
+    check_min_height(/*version=*/1, /*expected_min_height=*/-1);
+    check_min_height(/*version=*/2, /*expected_min_height=*/coin_height);
+    check_min_height(/*version=*/std::numeric_limits<uint32_t>::max(), /*expected_min_height=*/coin_height);
+}
+
 BOOST_AUTO_TEST_CASE(getvalueout_out_of_range_throws)
 {
     CMutableTransaction mtx;