test: exercise Schnorr signature cache in txvalidationcache_tests.cpp #35477

The Schnorr verification path of the signature cache is currently never hit in the unit tests, i.e. with the following patch they still pass:

diff --git a/src/script/sigcache.cpp b/src/script/sigcache.cpp
index c6fcc8f8eb..87688c1049 100644
--- a/src/script/sigcache.cpp
+++ b/src/script/sigcache.cpp
@@ -44,6 +44,7 @@ void SignatureCache::ComputeEntryECDSA(uint256& entry, const uint256& hash, cons
 
 void SignatureCache::ComputeEntrySchnorr(uint256& entry, const uint256& hash, std::span<const unsigned char> sig, const XOnlyPubKey& pubkey) const
 {
+    assert(false);
     CSHA256 hasher = m_salted_hasher_schnorr;
     hasher.Write(hash.begin(), 32).Write(pubkey.data(), pubkey.size()).Write(sig.data(), sig.size()).Finalize(entry.begin());
 }

This PR adds missing coverage for that by adding a Taproot key-path spend to checkinputs_test in txvalidationcache_tests.cpp. Same as for the already-existing ECDSA spends, the caching is tested across a large number of flag combinations (using ValidateCheckInputsForAllFlags), both with an invalid Schnorr signature (-> should only fail if SCRIPT_VERIFY_TAPROOT is set) and a valid one (-> should pass for all flag combinations).

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Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/35477.

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LLM Linter (✨ experimental)

Possible places where named args for integral literals may be used (e.g. func(x, /*named_arg=*/0) in C++, and func(x, named_arg=0) in Python):

• ValidateCheckInputsForAllFlags(CTransaction(tr_tx), SCRIPT_VERIFY_TAPROOT, true, m_node.chainman->ActiveChainstate().CoinsTip(), m_node.chainman->m_validation_cache) in src/test/txvalidationcache_tests.cpp

^{2026-06-07 02:04:10}

Concept ACK