Method CreateValidTransaction

src/test/util/setup_common.cpp:478–539

}

std::pair<CMutableTransaction, CAmount> TestChain100Setup::CreateValidTransaction(const std::vector<CTransactionRef>& input_transactions,
                                                                                  const std::vector<COutPoint>& inputs,
                                                                                  int input_height,
                                                                                  const std::vector<CKey>& input_signing_keys,
                                                                                  const std::vector<CTxOut>& outputs,
                                                                                  const std::optional<CFeeRate>& feerate,
                                                                                  const std::optional<uint32_t>& fee_output)
{
    CMutableTransaction mempool_txn;
    mempool_txn.vin.reserve(inputs.size());
    mempool_txn.vout.reserve(outputs.size());

    for (const auto& outpoint : inputs) {
        mempool_txn.vin.emplace_back(outpoint, CScript(), MAX_BIP125_RBF_SEQUENCE);
    }
    mempool_txn.vout = outputs;

    // - Add the signing key to a keystore
    FillableSigningProvider keystore;
    for (const auto& input_signing_key : input_signing_keys) {
        keystore.AddKey(input_signing_key);
    }
    // - Populate a CoinsViewCache with the unspent output
    CCoinsViewCache coins_cache{&CoinsViewEmpty::Get()};
    for (const auto& input_transaction : input_transactions) {
        AddCoins(coins_cache, *input_transaction.get(), input_height);
    }
    // Build Outpoint to Coin map for SignTransaction
    std::map<COutPoint, Coin> input_coins;
    CAmount inputs_amount{0};
    for (const auto& outpoint_to_spend : inputs) {
        // Use GetCoin to properly populate utxo_to_spend
        auto utxo_to_spend{coins_cache.GetCoin(outpoint_to_spend).value()};
        input_coins.insert({outpoint_to_spend, utxo_to_spend});
        inputs_amount += utxo_to_spend.out.nValue;
    }
    // - Default signature hashing type
    int nHashType = SIGHASH_ALL;
    std::map<int, bilingual_str> input_errors;
    assert(SignTransaction(mempool_txn, &keystore, input_coins, {.sighash_type = nHashType}, input_errors));
    CAmount current_fee = inputs_amount - std::accumulate(outputs.begin(), outputs.end(), CAmount(0),
        [](const CAmount& acc, const CTxOut& out) {
        return acc + out.nValue;
    });
    // Deduct fees from fee_output to meet feerate if set
    if (feerate.has_value()) {
        assert(fee_output.has_value());
        assert(fee_output.value() < mempool_txn.vout.size());
        CAmount target_fee = feerate.value().GetFee(GetVirtualTransactionSize(CTransaction{mempool_txn}));
        CAmount deduction = target_fee - current_fee;
        if (deduction > 0) {
            // Only deduct fee if there's anything to deduct. If the caller has put more fees than
            // the target feerate, don't change the fee.
            mempool_txn.vout[fee_output.value()].nValue -= deduction;
            // Re-sign since an output has changed
            input_errors.clear();
            assert(SignTransaction(mempool_txn, &keystore, input_coins, {.sighash_type = nHashType}, input_errors));
            current_fee = target_fee;