miner_tests.cpp

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// Copyright (c) 2011-2014 The Bitcoin Core developers
// Copyright (c) 2016-2021 The PIVX Core developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or https://www.opensource.org/licenses/mit-license.php.
 
#include "wallet/test/wallet_test_fixture.h"
 
#include "blockassembler.h"
#include "checkpoints.h"
#include "consensus/merkle.h"
#include "miner.h"
#include "pubkey.h"
#include "uint256.h"
#include "util/blockstatecatcher.h"
#include "util/system.h"
#include "validation.h"
#include "wallet/wallet.h"
 
#include <boost/test/unit_test.hpp>
 
 
// future: this should be MAINNET.
BOOST_FIXTURE_TEST_SUITE(miner_tests, WalletRegTestingSetup)
 
static
struct {
    unsigned char extranonce;
    unsigned int nonce;
} blockinfo[] = {
    {4, 0xa4a3e223}, {2, 0x15c32f9e}, {1, 0x0375b547}, {1, 0x7004a8a5},
    {2, 0xce440296}, {2, 0x52cfe198}, {1, 0x77a72cd0}, {2, 0xbb5d6f84},
    {2, 0x83f30c2c}, {1, 0x48a73d5b}, {1, 0xef7dcd01}, {2, 0x6809c6c4},
    {2, 0x0883ab3c}, {1, 0x087bbbe2}, {2, 0x2104a814}, {2, 0xdffb6daa},
    {1, 0xee8a0a08}, {2, 0xba4237c1}, {1, 0xa70349dc}, {1, 0x344722bb},
    {3, 0xd6294733}, {2, 0xec9f5c94}, {2, 0xca2fbc28}, {1, 0x6ba4f406},
    {2, 0x015d4532}, {1, 0x6e119b7c}, {2, 0x43e8f314}, {2, 0x27962f38},
    {2, 0xb571b51b}, {2, 0xb36bee23}, {2, 0xd17924a8}, {2, 0x6bc212d9},
    {1, 0x630d4948}, {2, 0x9a4c4ebb}, {2, 0x554be537}, {1, 0xd63ddfc7},
    {2, 0xa10acc11}, {1, 0x759a8363}, {2, 0xfb73090d}, {1, 0xe82c6a34},
    {1, 0xe33e92d7}, {3, 0x658ef5cb}, {2, 0xba32ff22}, {5, 0x0227a10c},
    {1, 0xa9a70155}, {5, 0xd096d809}, {1, 0x37176174}, {1, 0x830b8d0f},
    {1, 0xc6e3910e}, {2, 0x823f3ca8}, {1, 0x99850849}, {1, 0x7521fb81},
    {1, 0xaacaabab}, {1, 0xd645a2eb}, {5, 0x7aea1781}, {5, 0x9d6e4b78},
    {1, 0x4ce90fd8}, {1, 0xabdc832d}, {6, 0x4a34f32a}, {2, 0xf2524c1c},
    {2, 0x1bbeb08a}, {1, 0xad47f480}, {1, 0x9f026aeb}, {1, 0x15a95049},
    {2, 0xd1cb95b2}, {2, 0xf84bbda5}, {1, 0x0fa62cd1}, {1, 0xe05f9169},
    {1, 0x78d194a9}, {5, 0x3e38147b}, {5, 0x737ba0d4}, {1, 0x63378e10},
    {1, 0x6d5f91cf}, {2, 0x88612eb8}, {2, 0xe9639484}, {1, 0xb7fabc9d},
    {2, 0x19b01592}, {1, 0x5a90dd31}, {2, 0x5bd7e028}, {2, 0x94d00323},
    {1, 0xa9b9c01a}, {1, 0x3a40de61}, {1, 0x56e7eec7}, {5, 0x859f7ef6},
    {1, 0xfd8e5630}, {1, 0x2b0c9f7f}, {1, 0xba700e26}, {1, 0x7170a408},
    {1, 0x70de86a8}, {1, 0x74d64cd5}, {1, 0x49e738a1}, {2, 0x6910b602},
    {0, 0x643c565f}, {1, 0x54264b3f}, {2, 0x97ea6396}, {2, 0x55174459},
    {2, 0x03e8779a}, {1, 0x98f34d8f}, {1, 0xc07b2b07}, {1, 0xdfe29668},
    {1, 0x3141c7c1}, {1, 0xb3b595f4}, {1, 0x735abf08}, {5, 0x623bfbce},
    {2, 0xd351e722}, {1, 0xf4ca48c9}, {1, 0x5b19c670}, {1, 0xa164bf0e},
    {2, 0xbbbeb305}, {2, 0xfe1c810a},
};
 
// Test suite for ancestor feerate transaction selection.
// Implemented as an additional function, rather than a separate test case,
// to allow reusing the blockchain created in CreateNewBlock_validity.
void TestPackageSelection(const CChainParams& chainparams, CScript scriptPubKey, std::vector<CTransactionRef>& txFirst)
{
    // Test the ancestor feerate transaction selection.
    TestMemPoolEntryHelper entry;
 
    // Test that a medium fee transaction will be selected after a higher fee
    // rate package with a low fee rate parent.
    CMutableTransaction tx;
    tx.vin.resize(1);
    tx.vin[0].scriptSig = CScript() << OP_1;
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vin[0].prevout.n = 0;
    tx.vout.resize(1);
    tx.vout[0].nValue = 5000000000LL - 1000;
    // This tx has a low fee: 1000 satoshis
    uint256 hashParentTx = tx.GetHash(); // save this txid for later use
    mempool.addUnchecked(hashParentTx, entry.Fee(1000).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
 
    // This tx has a medium fee: 10000 satoshis
    tx.vin[0].prevout.hash = txFirst[1]->GetHash();
    tx.vout[0].nValue = 5000000000LL - 10000;
    uint256 hashMediumFeeTx = tx.GetHash();
    mempool.addUnchecked(hashMediumFeeTx, entry.Fee(10000).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
 
    // This tx has a high fee, but depends on the first transaction
    tx.vin[0].prevout.hash = hashParentTx;
    tx.vout[0].nValue = 5000000000LL - 1000 - 50000; // 50k satoshi fee
    uint256 hashHighFeeTx = tx.GetHash();
    mempool.addUnchecked(hashHighFeeTx, entry.Fee(50000).Time(GetTime()).SpendsCoinbaseOrCoinstake(false).FromTx(tx));
 
    std::unique_ptr<CBlockTemplate> pblocktemplate = BlockAssembler(chainparams, DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey);
 
    BOOST_CHECK(pblocktemplate->block.vtx[1]->GetHash() == hashParentTx);
    BOOST_CHECK(pblocktemplate->block.vtx[2]->GetHash() == hashHighFeeTx);
    BOOST_CHECK(pblocktemplate->block.vtx[3]->GetHash() == hashMediumFeeTx);
 
    // Test that a package below the min relay fee doesn't get included
    tx.vin[0].prevout.hash = hashHighFeeTx;
    tx.vout[0].nValue = 5000000000LL - 1000 - 50000; // 0 fee
    uint256 hashFreeTx = tx.GetHash();
    mempool.addUnchecked(hashFreeTx, entry.Fee(0).FromTx(tx));
    size_t freeTxSize = ::GetSerializeSize(tx, PROTOCOL_VERSION);
 
    // Calculate a fee on child transaction that will put the package just
    // below the min relay fee (assuming 1 child tx of the same size).
    CAmount feeToUse = minRelayTxFee.GetFee(2*freeTxSize) - 1;
 
    tx.vin[0].prevout.hash = hashFreeTx;
    tx.vout[0].nValue = 5000000000LL - 1000 - 50000 - feeToUse;
    uint256 hashLowFeeTx = tx.GetHash();
    mempool.addUnchecked(hashLowFeeTx, entry.Fee(feeToUse).FromTx(tx));
    pblocktemplate = BlockAssembler(chainparams, DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey);
    // Verify that the free tx and the low fee tx didn't get selected
    for (size_t i=0; i<pblocktemplate->block.vtx.size(); ++i) {
        BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashFreeTx);
        BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashLowFeeTx);
    }
 
    // Test that packages above the min relay fee do get included, even if one
    // of the transactions is below the min relay fee
    // Remove the low fee transaction and replace with a higher fee transaction
    mempool.removeRecursive(tx);
    tx.vout[0].nValue -= 2; // Now we should be just over the min relay fee
    hashLowFeeTx = tx.GetHash();
    mempool.addUnchecked(hashLowFeeTx, entry.Fee(feeToUse+2).FromTx(tx));
    pblocktemplate = BlockAssembler(chainparams, DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey);
    BOOST_CHECK(pblocktemplate->block.vtx[4]->GetHash() == hashFreeTx);
    BOOST_CHECK(pblocktemplate->block.vtx[5]->GetHash() == hashLowFeeTx);
 
    // Test that transaction selection properly updates ancestor fee
    // calculations as ancestor transactions get included in a block.
    // Add a 0-fee transaction that has 2 outputs.
    tx.vin[0].prevout.hash = txFirst[2]->GetHash();
    tx.vout.resize(2);
    tx.vout[0].nValue = 5000000000LL - 100000000;
    tx.vout[1].nValue = 100000000; // 1BTC output
    uint256 hashFreeTx2 = tx.GetHash();
    mempool.addUnchecked(hashFreeTx2, entry.Fee(0).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
 
    // This tx can't be mined by itself
    tx.vin[0].prevout.hash = hashFreeTx2;
    tx.vout.resize(1);
    feeToUse = minRelayTxFee.GetFee(freeTxSize);
    tx.vout[0].nValue = 5000000000LL - 100000000 - feeToUse;
    uint256 hashLowFeeTx2 = tx.GetHash();
    mempool.addUnchecked(hashLowFeeTx2, entry.Fee(feeToUse).SpendsCoinbaseOrCoinstake(false).FromTx(tx));
    pblocktemplate = BlockAssembler(chainparams, DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey);
 
    // Verify that this tx isn't selected.
    for (size_t i=0; i<pblocktemplate->block.vtx.size(); ++i) {
        BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashFreeTx2);
        BOOST_CHECK(pblocktemplate->block.vtx[i]->GetHash() != hashLowFeeTx2);
    }
 
    // This tx will be mineable, and should cause hashLowFeeTx2 to be selected
    // as well.
    tx.vin[0].prevout.n = 1;
    tx.vout[0].nValue = 100000000 - 10000; // 10k satoshi fee
    mempool.addUnchecked(tx.GetHash(), entry.Fee(10000).FromTx(tx));
    pblocktemplate = BlockAssembler(chainparams, DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey);
    BOOST_CHECK(pblocktemplate->block.vtx[8]->GetHash() == hashLowFeeTx2);
}
 
// NOTE: These tests rely on CreateNewBlock doing its own self-validation!
BOOST_AUTO_TEST_CASE(CreateNewBlock_validity)
{
    // Note that by default, these tests run with size accounting enabled.
    const CChainParams& chainparams = Params();
    CScript scriptPubKey = CScript() << OP_DUP << OP_HASH160 << ParseHex("8d5b4f83212214d6ef693e02e6d71969fddad976") << OP_EQUALVERIFY << OP_CHECKSIG;
 
    std::unique_ptr<CBlockTemplate> pblocktemplate;
    CMutableTransaction tx,tx2;
    CScript script;
    uint256 hash;
    TestMemPoolEntryHelper entry;
    entry.nFee = 11;
    entry.nHeight = 11;
 
    Checkpoints::fEnabled = false;
 
    // Simple block creation, nothing special yet:
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
    // Set genesis block
    pblocktemplate->block.hashPrevBlock = chainparams.GetConsensus().hashGenesisBlock;
 
    // We can't make transactions until we have inputs
    // Therefore, load 100 blocks :)
    std::vector<CTransactionRef>txFirst;
    std::shared_ptr<CBlock> pblock = std::make_shared<CBlock>(pblocktemplate->block); // pointer for convenience
    for (unsigned int i = 0; i < sizeof(blockinfo)/sizeof(*blockinfo); ++i) {
        CBlockIndex* pindexPrev = WITH_LOCK(cs_main, return chainActive.Tip());
        assert(pindexPrev);
        pblock->nTime = pindexPrev->GetMedianTimePast() + 60;
        pblock->vtx.clear(); // Update coinbase input height manually
        CreateCoinbaseTx(pblock.get(), CScript(), pindexPrev);
        if (txFirst.size() < 4)
            txFirst.emplace_back(pblock->vtx[0]);
        pblock->hashMerkleRoot = BlockMerkleRoot(*pblock);
        pblock->nNonce = blockinfo[i].nonce;
        BlockStateCatcherWrapper stateCatcher(pblock->GetHash());
        stateCatcher.registerEvent();
        BOOST_CHECK(ProcessNewBlock(pblock, nullptr));
        SyncWithValidationInterfaceQueue();
        BOOST_CHECK(stateCatcher.get().found && stateCatcher.get().state.IsValid());
        pblock->hashPrevBlock = pblock->GetHash();
    }
 
    // Just to make sure we can still make simple blocks
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
 
    // block sigops > limit: 2000 CHECKMULTISIG + 1
    tx.vin.resize(1);
    // NOTE: OP_NOP is used to force 20 SigOps for the CHECKMULTISIG
    tx.vin[0].scriptSig = CScript() << OP_0 << OP_0 << OP_0 << OP_NOP << OP_CHECKMULTISIG << OP_1;
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vin[0].prevout.n = 0;
    tx.vout.resize(1);
    tx.vout[0].nValue = 5000000000LL;
    for (unsigned int i = 0; i < 2001; ++i) {
        tx.vout[0].nValue -= 1000000;
        hash = tx.GetHash();
        bool spendsCoinbase = (i == 0) ? true : false; // only first tx spends coinbase
        // If we don't set the # of sig ops in the CTxMemPoolEntry, template creation fails
        mempool.addUnchecked(hash, entry.Fee(1000000).Time(GetTime()).SpendsCoinbaseOrCoinstake(spendsCoinbase).FromTx(tx));
        tx.vin[0].prevout.hash = hash;
    }
    BOOST_CHECK_EXCEPTION(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false), std::runtime_error, HasReason("bad-blk-sigops"));
    mempool.clear();
 
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vout[0].nValue = 5000000000LL;
    for (unsigned int i = 0; i < 1001; ++i) {
        tx.vout[0].nValue -= 1000000;
        hash = tx.GetHash();
        bool spendsCoinbase = (i == 0) ? true : false; // only first tx spends coinbase
        // If we do set the # of sig ops in the CTxMemPoolEntry, template creation passes
        mempool.addUnchecked(hash, entry.Fee(1000000).Time(GetTime()).SpendsCoinbaseOrCoinstake(spendsCoinbase).SigOps(20).FromTx(tx));
        tx.vin[0].prevout.hash = hash;
    }
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
    mempool.clear();
 
    // block size > limit
    tx.vin[0].scriptSig = CScript();
    // 18 * (520char + DROP) + OP_1 = 9433 bytes
    std::vector<unsigned char> vchData(520);
    for (unsigned int i = 0; i < 18; ++i)
        tx.vin[0].scriptSig << vchData << OP_DROP;
    tx.vin[0].scriptSig << OP_1;
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vin[0].prevout.n = 0;
    tx.vout[0].nValue = 5000000000LL;
    for (unsigned int i = 0; i < 215; ++i) {
        tx.vout[0].nValue -= 10000000;
        hash = tx.GetHash();
        bool spendsCoinbase = i == 0; // only first tx spends coinbase
        mempool.addUnchecked(hash, entry.Fee(1000000).Time(GetTime()).SpendsCoinbaseOrCoinstake(spendsCoinbase).FromTx(tx));
        tx.vin[0].prevout.hash = hash;
    }
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
    mempool.clear();
 
    // orphan in mempool, template creation fails
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(1000000).Time(GetTime()).FromTx(tx));
    BOOST_CHECK_EXCEPTION(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false), std::runtime_error, HasReason("bad-txns-inputs-missingorspent"));
    mempool.clear();
 
    // child with higher feerate than parent
    tx.vin[0].scriptSig = CScript() << OP_1;
    tx.vin[0].prevout.hash = txFirst[1]->GetHash();
    tx.vout[0].nValue = 4900000000LL;
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(100000000LL).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
    tx.vin[0].prevout.hash = hash;
    tx.vin.resize(2);
    tx.vin[1].scriptSig = CScript() << OP_1;
    tx.vin[1].prevout.hash = txFirst[0]->GetHash();
    tx.vin[1].prevout.n = 0;
    tx.vout[0].nValue = 5900000000LL;
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(400000000LL).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
    mempool.clear();
 
    // coinbase in mempool, template creation fails
    tx.vin.resize(1);
    tx.vin[0].prevout.SetNull();
    tx.vin[0].scriptSig = CScript() << OP_0 << OP_1;
    tx.vout[0].nValue = 0;
    hash = tx.GetHash();
    // give it a fee so it'll get mined
    mempool.addUnchecked(hash, entry.Fee(100000).Time(GetTime()).SpendsCoinbaseOrCoinstake(false).FromTx(tx));
    BOOST_CHECK_EXCEPTION(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false), std::runtime_error, HasReason("bad-cb-multiple"));
    mempool.clear();
 
    // invalid (pre-p2sh) txn in mempool, template creation fails
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vin[0].prevout.n = 0;
    tx.vin[0].scriptSig = CScript() << OP_1;
    tx.vout[0].nValue = 4900000000LL;
    script = CScript() << OP_0;
    tx.vout[0].scriptPubKey = GetScriptForDestination(CScriptID(script));
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(10000000L).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
    tx.vin[0].prevout.hash = hash;
    tx.vin[0].scriptSig = CScript() << std::vector<unsigned char>(script.begin(), script.end());
    tx.vout[0].nValue -= 1000000;
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(1000000).Time(GetTime()).SpendsCoinbaseOrCoinstake(false).FromTx(tx));
     // Should throw block-validation-failed
    BOOST_CHECK_EXCEPTION(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false), std::runtime_error, HasReason("block-validation-failed"));
    mempool.clear();
 
    // double spend txn pair in mempool, template creation fails
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vin[0].scriptSig = CScript() << OP_1;
    tx.vout[0].nValue = 4900000000LL;
    tx.vout[0].scriptPubKey = CScript() << OP_1;
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(100000000L).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
    tx.vout[0].scriptPubKey = CScript() << OP_2;
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(100000000L).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
    BOOST_CHECK_EXCEPTION(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false), std::runtime_error, HasReason("bad-txns-inputs-missingorspent"));
    mempool.clear();
 
    // non-final txs in mempool
    SetMockTime(WITH_LOCK(cs_main, return chainActive.Tip()->GetMedianTimePast()+1));
 
    // height locked
    tx.vin[0].prevout.hash = txFirst[0]->GetHash();
    tx.vin[0].scriptSig = CScript() << OP_1;
    tx.vin[0].nSequence = 0;
    tx.vout[0].nValue = 4900000000LL;
    tx.vout[0].scriptPubKey = CScript() << OP_1;
    tx.nLockTime = WITH_LOCK(cs_main, return chainActive.Tip()->nHeight+1);
    hash = tx.GetHash();
    mempool.addUnchecked(hash, entry.Fee(100000000L).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx));
    { LOCK(cs_main); BOOST_CHECK(!CheckFinalTx(MakeTransactionRef(tx), LOCKTIME_MEDIAN_TIME_PAST)); }
 
    // time locked
    tx2.vin.resize(1);
    tx2.vin[0].prevout.hash = txFirst[1]->GetHash();
    tx2.vin[0].prevout.n = 0;
    tx2.vin[0].scriptSig = CScript() << OP_1;
    tx2.vin[0].nSequence = 0;
    tx2.vout.resize(1);
    tx2.vout[0].nValue = 4900000000LL;
    tx2.vout[0].scriptPubKey = CScript() << OP_1;
    tx2.nLockTime = WITH_LOCK(cs_main, return chainActive.Tip()->GetMedianTimePast()+1);
    hash = tx2.GetHash();
    mempool.addUnchecked(hash, entry.Fee(100000000L).Time(GetTime()).SpendsCoinbaseOrCoinstake(true).FromTx(tx2));
    { LOCK(cs_main); BOOST_CHECK(!CheckFinalTx(MakeTransactionRef(tx2), LOCKTIME_MEDIAN_TIME_PAST)); }
 
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
 
    // Neither tx should have make it into the template.
    BOOST_CHECK_EQUAL(pblocktemplate->block.vtx.size(), 1);
 
    {
        LOCK(cs_main);
        // However if we advance height and time by one, both will.
        chainActive.Tip()->nHeight++;
        SetMockTime(chainActive.Tip()->GetMedianTimePast() + 2);
    }
 
    // FIXME: we should *actually* create a new block so the following test
    //        works; CheckFinalTx() isn't fooled by monkey-patching nHeight.
    //BOOST_CHECK(CheckFinalTx(tx));
    //BOOST_CHECK(CheckFinalTx(tx2));
 
    BOOST_CHECK(pblocktemplate = BlockAssembler(Params(), DEFAULT_PRINTPRIORITY).CreateNewBlock(scriptPubKey, &m_wallet, false));
    BOOST_CHECK_EQUAL(pblocktemplate->block.vtx.size(), 3);
 
    WITH_LOCK(cs_main, chainActive.Tip()->nHeight--);
    SetMockTime(0);
    mempool.clear();
 
    TestPackageSelection(chainparams, scriptPubKey, txFirst);
 
    Checkpoints::fEnabled = true;
}
 
BOOST_AUTO_TEST_SUITE_END()