refactor: test/bench: dedup Build{Crediting,Spending}Transaction()

prototypes used in src/test/script_tests.cpp:
- CMutableTransaction BuildCreditingTransaction(const CScript& scriptPubKey, int nValue = 0);
- CMutableTransaction BuildSpendingTransaction(const CScript& scriptSig, const CScriptWitness& scriptWitness, const CTransaction& txCredit);

prototypes used in bench/verify_script.cpp:
- CMutableTransaction BuildCreditingTransaction(const CScript& scriptPubKey);
- CMutableTransaction BuildSpendingTransaction(const CScript& scriptSig, const CMutableTransaction& txCredit);

The more generic versions from the script tests are moved into a new file pair
transaction_utils.cpp/h and the calls are adapted accordingly in the
verify_script benchmark (passing the nValue of 1 explicitely for
BuildCreditingTransaction(), passing empty scriptWitness explicitely and
converting txCredit parameter to CTransaction in BuildSpendingTransaction()).

1 files changed, 3 insertions, 37 deletions

diff --git a/src/bench/verify_script.cpp b/src/bench/verify_script.cpp
index 4891c57b3a..c9947f192e 100644
--- a/src/bench/verify_script.cpp
+++ b/src/bench/verify_script.cpp
@@ -10,44 +10,10 @@
 #include <script/script.h>
 #include <script/standard.h>
 #include <streams.h>
+#include <test/lib/transaction_utils.h>
 
 #include <array>
 
-// FIXME: Dedup with BuildCreditingTransaction in test/script_tests.cpp.
-static CMutableTransaction BuildCreditingTransaction(const CScript& scriptPubKey)
-{
-    CMutableTransaction txCredit;
-    txCredit.nVersion = 1;
-    txCredit.nLockTime = 0;
-    txCredit.vin.resize(1);
-    txCredit.vout.resize(1);
-    txCredit.vin[0].prevout.SetNull();
-    txCredit.vin[0].scriptSig = CScript() << CScriptNum(0) << CScriptNum(0);
-    txCredit.vin[0].nSequence = CTxIn::SEQUENCE_FINAL;
-    txCredit.vout[0].scriptPubKey = scriptPubKey;
-    txCredit.vout[0].nValue = 1;
-
-    return txCredit;
-}
-
-// FIXME: Dedup with BuildSpendingTransaction in test/script_tests.cpp.
-static CMutableTransaction BuildSpendingTransaction(const CScript& scriptSig, const CMutableTransaction& txCredit)
-{
-    CMutableTransaction txSpend;
-    txSpend.nVersion = 1;
-    txSpend.nLockTime = 0;
-    txSpend.vin.resize(1);
-    txSpend.vout.resize(1);
-    txSpend.vin[0].prevout.hash = txCredit.GetHash();
-    txSpend.vin[0].prevout.n = 0;
-    txSpend.vin[0].scriptSig = scriptSig;
-    txSpend.vin[0].nSequence = CTxIn::SEQUENCE_FINAL;
-    txSpend.vout[0].scriptPubKey = CScript();
-    txSpend.vout[0].nValue = txCredit.vout[0].nValue;
-
-    return txSpend;
-}
-
 // Microbenchmark for verification of a basic P2WPKH script. Can be easily
 // modified to measure performance of other types of scripts.
 static void VerifyScriptBench(benchmark::State& state)
@@ -71,8 +37,8 @@ static void VerifyScriptBench(benchmark::State& state)
     CScript scriptPubKey = CScript() << witnessversion << ToByteVector(pubkeyHash);
     CScript scriptSig;
     CScript witScriptPubkey = CScript() << OP_DUP << OP_HASH160 << ToByteVector(pubkeyHash) << OP_EQUALVERIFY << OP_CHECKSIG;
-    const CMutableTransaction& txCredit = BuildCreditingTransaction(scriptPubKey);
-    CMutableTransaction txSpend = BuildSpendingTransaction(scriptSig, txCredit);
+    const CMutableTransaction& txCredit = BuildCreditingTransaction(scriptPubKey, 1);
+    CMutableTransaction txSpend = BuildSpendingTransaction(scriptSig, CScriptWitness(), CTransaction(txCredit));
     CScriptWitness& witness = txSpend.vin[0].scriptWitness;
     witness.stack.emplace_back();
     key.Sign(SignatureHash(witScriptPubkey, txSpend, 0, SIGHASH_ALL, txCredit.vout[0].nValue, SigVersion::WITNESS_V0), witness.stack.back());