coinselector__tests_8cpp_source.html

// Copyright (c) 2017-2020 The Bitcoin Core developers

// Distributed under the MIT software license, see the accompanying

// file COPYING or http://www.opensource.org/licenses/mit-license.php.


#include <consensus/amount.h>

#include <node/context.h>

#include <primitives/transaction.h>

#include <random.h>

#include <test/util/setup_common.h>

#include <util/translation.h>

#include <wallet/coincontrol.h>

#include <wallet/coinselection.h>

#include <wallet/spend.h>

#include <wallet/test/wallet_test_fixture.h>

#include <wallet/wallet.h>


#include <boost/test/unit_test.hpp>

#include <random>


BOOST_FIXTURE_TEST_SUITE(coinselector_tests, WalletTestingSetup)


// how many times to run all the tests to have a chance to catch errors that only show up with particular random shuffles

#define RUN_TESTS 100


// some tests fail 1% of the time due to bad luck.

// we repeat those tests this many times and only complain if all iterations of the test fail

#define RANDOM_REPEATS 5


typedef std::set<CInputCoin> CoinSet;


static const CoinEligibilityFilter filter_standard(1, 6, 0);

static const CoinEligibilityFilter filter_confirmed(1, 1, 0);

static const CoinEligibilityFilter filter_standard_extra(6, 6, 0);


static void add_coin(const CAmount& nValue, int nInput, std::vector<CInputCoin>& set)

{

    CMutableTransaction tx;

    tx.vout.resize(nInput + 1);

    tx.vout[nInput].nValue = nValue;

    set.emplace_back(MakeTransactionRef(tx), nInput);

}


static void add_coin(const CAmount& nValue, int nInput, CoinSet& set, CAmount fee = 0, CAmount long_term_fee = 0)

{

    CMutableTransaction tx;

    tx.vout.resize(nInput + 1);

    tx.vout[nInput].nValue = nValue;

    CInputCoin coin(MakeTransactionRef(tx), nInput);

    coin.effective_value = nValue - fee;

    coin.m_fee = fee;

    coin.m_long_term_fee = long_term_fee;

    set.insert(coin);

}


static void add_coin(std::vector<COutput>& coins, CWallet& wallet, const CAmount& nValue, int nAge = 6*24, bool fIsFromMe = false, int nInput=0, bool spendable = false)

{

    static int nextLockTime = 0;

    CMutableTransaction tx;

    tx.nLockTime = nextLockTime++;        // so all transactions get different hashes

    tx.vout.resize(nInput + 1);

    tx.vout[nInput].nValue = nValue;

    if (spendable) {

        CTxDestination dest;

        bilingual_str error;

        const bool destination_ok = wallet.GetNewDestination(OutputType::BECH32, "", dest, error);

        assert(destination_ok);

        tx.vout[nInput].scriptPubKey = GetScriptForDestination(dest);

    }

    if (fIsFromMe) {

        // IsFromMe() returns (GetDebit() > 0), and GetDebit() is 0 if vin.empty(),

        // so stop vin being empty, and cache a non-zero Debit to fake out IsFromMe()

        tx.vin.resize(1);

    }

    uint256 txid = tx.GetHash();


    LOCK(wallet.cs_wallet);

    auto ret = wallet.mapWallet.emplace(std::piecewise_construct, std::forward_as_tuple(txid), std::forward_as_tuple(MakeTransactionRef(std::move(tx))));

    assert(ret.second);

    CWalletTx& wtx = (*ret.first).second;

    if (fIsFromMe)

    {

        wtx.m_amounts[CWalletTx::DEBIT].Set(ISMINE_SPENDABLE, 1);

        wtx.m_is_cache_empty = false;

    }

    COutput output(wallet, wtx, nInput, nAge, true /* spendable */, true /* solvable */, true /* safe */);

    coins.push_back(output);

}


static bool equal_sets(CoinSet a, CoinSet b)

{

    std::pair<CoinSet::iterator, CoinSet::iterator> ret = mismatch(a.begin(), a.end(), b.begin());

    return ret.first == a.end() && ret.second == b.end();

}


static CAmount make_hard_case(int utxos, std::vector<CInputCoin>& utxo_pool)

{

    utxo_pool.clear();

    CAmount target = 0;

    for (int i = 0; i < utxos; ++i) {

        target += (CAmount)1 << (utxos+i);

        add_coin((CAmount)1 << (utxos+i), 2*i, utxo_pool);

        add_coin(((CAmount)1 << (utxos+i)) + ((CAmount)1 << (utxos-1-i)), 2*i + 1, utxo_pool);

    }

    return target;

}


inline std::vector<OutputGroup>& GroupCoins(const std::vector<CInputCoin>& coins)

{

    static std::vector<OutputGroup> static_groups;

    static_groups.clear();

    for (auto& coin : coins) {

        static_groups.emplace_back();

        static_groups.back().Insert(coin, 0, true, 0, 0, false);

    }

    return static_groups;

}


inline std::vector<OutputGroup>& GroupCoins(const std::vector<COutput>& coins)

{

    static std::vector<OutputGroup> static_groups;

    static_groups.clear();

    for (auto& coin : coins) {

        static_groups.emplace_back();

        static_groups.back().Insert(coin.GetInputCoin(), coin.nDepth, coin.tx->m_amounts[CWalletTx::DEBIT].m_cached[ISMINE_SPENDABLE] && coin.tx->m_amounts[CWalletTx::DEBIT].m_value[ISMINE_SPENDABLE] == 1 /* HACK: we can't figure out the is_me flag so we use the conditions defined above; perhaps set safe to false for !fIsFromMe in add_coin() */, 0, 0, false);

    }

    return static_groups;

}


inline std::vector<OutputGroup>& KnapsackGroupOutputs(const std::vector<COutput>& coins, CWallet& wallet, const CoinEligibilityFilter& filter)

{

    CoinSelectionParams coin_selection_params(/* change_output_size= */ 0,

                                              /* change_spend_size= */ 0, /* effective_feerate= */ CFeeRate(0),

                                              /* long_term_feerate= */ CFeeRate(0), /* discard_feerate= */ CFeeRate(0),

                                              /* tx_noinputs_size= */ 0, /* avoid_partial= */ false);

    static std::vector<OutputGroup> static_groups;

    static_groups = GroupOutputs(wallet, coins, coin_selection_params, filter, /* positive_only */false);

    return static_groups;

}


// Branch and bound coin selection tests

BOOST_AUTO_TEST_CASE(bnb_search_test)

{

    // Setup

    std::vector<CInputCoin> utxo_pool;

    CoinSet selection;

    CoinSet actual_selection;

    CAmount value_ret = 0;


    // Known Outcome tests //


    // Empty utxo pool

    BOOST_CHECK(!SelectCoinsBnB(GroupCoins(utxo_pool), 1 * CENT, 0.5 * CENT, selection, value_ret));

    selection.clear();


    // Add utxos

    add_coin(1 * CENT, 1, utxo_pool);

    add_coin(2 * CENT, 2, utxo_pool);

    add_coin(3 * CENT, 3, utxo_pool);

    add_coin(4 * CENT, 4, utxo_pool);


    // Select 1 Cent

    add_coin(1 * CENT, 1, actual_selection);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 1 * CENT, 0.5 * CENT, selection, value_ret));

    BOOST_CHECK(equal_sets(selection, actual_selection));

    BOOST_CHECK_EQUAL(value_ret, 1 * CENT);

    actual_selection.clear();

    selection.clear();


    // Select 2 Cent

    add_coin(2 * CENT, 2, actual_selection);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 2 * CENT, 0.5 * CENT, selection, value_ret));

    BOOST_CHECK(equal_sets(selection, actual_selection));

    BOOST_CHECK_EQUAL(value_ret, 2 * CENT);

    actual_selection.clear();

    selection.clear();


    // Select 5 Cent

    add_coin(4 * CENT, 4, actual_selection);

    add_coin(1 * CENT, 1, actual_selection);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 5 * CENT, 0.5 * CENT, selection, value_ret));

    BOOST_CHECK(equal_sets(selection, actual_selection));

    BOOST_CHECK_EQUAL(value_ret, 5 * CENT);

    actual_selection.clear();

    selection.clear();


    // Select 11 Cent, not possible

    BOOST_CHECK(!SelectCoinsBnB(GroupCoins(utxo_pool), 11 * CENT, 0.5 * CENT, selection, value_ret));

    actual_selection.clear();

    selection.clear();


    // Cost of change is greater than the difference between target value and utxo sum

    add_coin(1 * CENT, 1, actual_selection);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 0.9 * CENT, 0.5 * CENT, selection, value_ret));

    BOOST_CHECK_EQUAL(value_ret, 1 * CENT);

    BOOST_CHECK(equal_sets(selection, actual_selection));

    actual_selection.clear();

    selection.clear();


    // Cost of change is less than the difference between target value and utxo sum

    BOOST_CHECK(!SelectCoinsBnB(GroupCoins(utxo_pool), 0.9 * CENT, 0, selection, value_ret));

    actual_selection.clear();

    selection.clear();


    // Select 10 Cent

    add_coin(5 * CENT, 5, utxo_pool);

    add_coin(5 * CENT, 5, actual_selection);

    add_coin(4 * CENT, 4, actual_selection);

    add_coin(1 * CENT, 1, actual_selection);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 10 * CENT, 0.5 * CENT, selection, value_ret));

    BOOST_CHECK(equal_sets(selection, actual_selection));

    BOOST_CHECK_EQUAL(value_ret, 10 * CENT);

    actual_selection.clear();

    selection.clear();


    // Negative effective value

    // Select 10 Cent but have 1 Cent not be possible because too small

    add_coin(5 * CENT, 5, actual_selection);

    add_coin(3 * CENT, 3, actual_selection);

    add_coin(2 * CENT, 2, actual_selection);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 10 * CENT, 5000, selection, value_ret));

    BOOST_CHECK_EQUAL(value_ret, 10 * CENT);

    // FIXME: this test is redundant with the above, because 1 Cent is selected, not "too small"

    // BOOST_CHECK(equal_sets(selection, actual_selection));


    // Select 0.25 Cent, not possible

    BOOST_CHECK(!SelectCoinsBnB(GroupCoins(utxo_pool), 0.25 * CENT, 0.5 * CENT, selection, value_ret));

    actual_selection.clear();

    selection.clear();


    // Iteration exhaustion test

    CAmount target = make_hard_case(17, utxo_pool);

    BOOST_CHECK(!SelectCoinsBnB(GroupCoins(utxo_pool), target, 0, selection, value_ret)); // Should exhaust

    target = make_hard_case(14, utxo_pool);

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), target, 0, selection, value_ret)); // Should not exhaust


    // Test same value early bailout optimization

    utxo_pool.clear();

    add_coin(7 * CENT, 7, actual_selection);

    add_coin(7 * CENT, 7, actual_selection);

    add_coin(7 * CENT, 7, actual_selection);

    add_coin(7 * CENT, 7, actual_selection);

    add_coin(2 * CENT, 7, actual_selection);

    add_coin(7 * CENT, 7, utxo_pool);

    add_coin(7 * CENT, 7, utxo_pool);

    add_coin(7 * CENT, 7, utxo_pool);

    add_coin(7 * CENT, 7, utxo_pool);

    add_coin(2 * CENT, 7, utxo_pool);

    for (int i = 0; i < 50000; ++i) {

        add_coin(5 * CENT, 7, utxo_pool);

    }

    BOOST_CHECK(SelectCoinsBnB(GroupCoins(utxo_pool), 30 * CENT, 5000, selection, value_ret));

    BOOST_CHECK_EQUAL(value_ret, 30 * CENT);

    BOOST_CHECK(equal_sets(selection, actual_selection));


    // Behavior tests //

    // Select 1 Cent with pool of only greater than 5 Cent

    utxo_pool.clear();

    for (int i = 5; i <= 20; ++i) {

        add_coin(i * CENT, i, utxo_pool);

    }

    // Run 100 times, to make sure it is never finding a solution

    for (int i = 0; i < 100; ++i) {

        BOOST_CHECK(!SelectCoinsBnB(GroupCoins(utxo_pool), 1 * CENT, 2 * CENT, selection, value_ret));

    }


    // Make sure that effective value is working in AttemptSelection when BnB is used

    CoinSelectionParams coin_selection_params_bnb(/* change_output_size= */ 0,

                                                  /* change_spend_size= */ 0, /* effective_feerate= */ CFeeRate(3000),

                                                  /* long_term_feerate= */ CFeeRate(1000), /* discard_feerate= */ CFeeRate(1000),

                                                  /* tx_noinputs_size= */ 0, /* avoid_partial= */ false);

    {

        std::unique_ptr<CWallet> wallet = std::make_unique<CWallet>(m_node.chain.get(), "", CreateMockWalletDatabase());

        wallet->LoadWallet();

        LOCK(wallet->cs_wallet);

        wallet->SetWalletFlag(WALLET_FLAG_DESCRIPTORS);

        wallet->SetupDescriptorScriptPubKeyMans();


        std::vector<COutput> coins;

        CoinSet setCoinsRet;

        CAmount nValueRet;


        add_coin(coins, *wallet, 1);

        coins.at(0).nInputBytes = 40; // Make sure that it has a negative effective value. The next check should assert if this somehow got through. Otherwise it will fail

        BOOST_CHECK(!SelectCoinsBnB(GroupCoins(coins), 1 * CENT, coin_selection_params_bnb.m_cost_of_change, setCoinsRet, nValueRet));


        // Test fees subtracted from output:

        coins.clear();

        add_coin(coins, *wallet, 1 * CENT);

        coins.at(0).nInputBytes = 40;

        coin_selection_params_bnb.m_subtract_fee_outputs = true;

        BOOST_CHECK(SelectCoinsBnB(GroupCoins(coins), 1 * CENT, coin_selection_params_bnb.m_cost_of_change, setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 1 * CENT);

    }


    {

        std::unique_ptr<CWallet> wallet = std::make_unique<CWallet>(m_node.chain.get(), "", CreateMockWalletDatabase());

        wallet->LoadWallet();

        LOCK(wallet->cs_wallet);

        wallet->SetWalletFlag(WALLET_FLAG_DESCRIPTORS);

        wallet->SetupDescriptorScriptPubKeyMans();


        std::vector<COutput> coins;

        CoinSet setCoinsRet;

        CAmount nValueRet;


        add_coin(coins, *wallet, 5 * CENT, 6 * 24, false, 0, true);

        add_coin(coins, *wallet, 3 * CENT, 6 * 24, false, 0, true);

        add_coin(coins, *wallet, 2 * CENT, 6 * 24, false, 0, true);

        CCoinControl coin_control;

        coin_control.fAllowOtherInputs = true;

        coin_control.Select(COutPoint(coins.at(0).tx->GetHash(), coins.at(0).i));

        coin_selection_params_bnb.m_effective_feerate = CFeeRate(0);

        BOOST_CHECK(SelectCoins(*wallet, coins, 10 * CENT, setCoinsRet, nValueRet, coin_control, coin_selection_params_bnb));

    }

}


BOOST_AUTO_TEST_CASE(knapsack_solver_test)

{

    std::unique_ptr<CWallet> wallet = std::make_unique<CWallet>(m_node.chain.get(), "", CreateMockWalletDatabase());

    wallet->LoadWallet();

    LOCK(wallet->cs_wallet);

    wallet->SetWalletFlag(WALLET_FLAG_DESCRIPTORS);

    wallet->SetupDescriptorScriptPubKeyMans();


    CoinSet setCoinsRet, setCoinsRet2;

    CAmount nValueRet;

    std::vector<COutput> coins;


    // test multiple times to allow for differences in the shuffle order

    for (int i = 0; i < RUN_TESTS; i++)

    {

        coins.clear();


        // with an empty wallet we can't even pay one cent

        BOOST_CHECK(!KnapsackSolver(1 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_standard), setCoinsRet, nValueRet));


        add_coin(coins, *wallet, 1*CENT, 4);        // add a new 1 cent coin


        // with a new 1 cent coin, we still can't find a mature 1 cent

        BOOST_CHECK(!KnapsackSolver(1 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_standard), setCoinsRet, nValueRet));


        // but we can find a new 1 cent

        BOOST_CHECK(KnapsackSolver(1 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 1 * CENT);


        add_coin(coins, *wallet, 2*CENT);           // add a mature 2 cent coin


        // we can't make 3 cents of mature coins

        BOOST_CHECK(!KnapsackSolver(3 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_standard), setCoinsRet, nValueRet));


        // we can make 3 cents of new coins

        BOOST_CHECK(KnapsackSolver(3 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 3 * CENT);


        add_coin(coins, *wallet, 5*CENT);           // add a mature 5 cent coin,

        add_coin(coins, *wallet, 10*CENT, 3, true); // a new 10 cent coin sent from one of our own addresses

        add_coin(coins, *wallet, 20*CENT);          // and a mature 20 cent coin


        // now we have new: 1+10=11 (of which 10 was self-sent), and mature: 2+5+20=27.  total = 38


        // we can't make 38 cents only if we disallow new coins:

        BOOST_CHECK(!KnapsackSolver(38 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_standard), setCoinsRet, nValueRet));

        // we can't even make 37 cents if we don't allow new coins even if they're from us

        BOOST_CHECK(!KnapsackSolver(38 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_standard_extra), setCoinsRet, nValueRet));

        // but we can make 37 cents if we accept new coins from ourself

        BOOST_CHECK(KnapsackSolver(37 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_standard), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 37 * CENT);

        // and we can make 38 cents if we accept all new coins

        BOOST_CHECK(KnapsackSolver(38 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 38 * CENT);


        // try making 34 cents from 1,2,5,10,20 - we can't do it exactly

        BOOST_CHECK(KnapsackSolver(34 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 35 * CENT);       // but 35 cents is closest

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);     // the best should be 20+10+5.  it's incredibly unlikely the 1 or 2 got included (but possible)


        // when we try making 7 cents, the smaller coins (1,2,5) are enough.  We should see just 2+5

        BOOST_CHECK(KnapsackSolver(7 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 7 * CENT);

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);


        // when we try making 8 cents, the smaller coins (1,2,5) are exactly enough.

        BOOST_CHECK(KnapsackSolver(8 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK(nValueRet == 8 * CENT);

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);


        // when we try making 9 cents, no subset of smaller coins is enough, and we get the next bigger coin (10)

        BOOST_CHECK(KnapsackSolver(9 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 10 * CENT);

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);


        // now clear out the wallet and start again to test choosing between subsets of smaller coins and the next biggest coin

        coins.clear();


        add_coin(coins, *wallet,  6*CENT);

        add_coin(coins, *wallet,  7*CENT);

        add_coin(coins, *wallet,  8*CENT);

        add_coin(coins, *wallet, 20*CENT);

        add_coin(coins, *wallet, 30*CENT); // now we have 6+7+8+20+30 = 71 cents total


        // check that we have 71 and not 72

        BOOST_CHECK(KnapsackSolver(71 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK(!KnapsackSolver(72 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));


        // now try making 16 cents.  the best smaller coins can do is 6+7+8 = 21; not as good at the next biggest coin, 20

        BOOST_CHECK(KnapsackSolver(16 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 20 * CENT); // we should get 20 in one coin

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);


        add_coin(coins, *wallet,  5*CENT); // now we have 5+6+7+8+20+30 = 75 cents total


        // now if we try making 16 cents again, the smaller coins can make 5+6+7 = 18 cents, better than the next biggest coin, 20

        BOOST_CHECK(KnapsackSolver(16 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 18 * CENT); // we should get 18 in 3 coins

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);


        add_coin(coins, *wallet,  18*CENT); // now we have 5+6+7+8+18+20+30


        // and now if we try making 16 cents again, the smaller coins can make 5+6+7 = 18 cents, the same as the next biggest coin, 18

        BOOST_CHECK(KnapsackSolver(16 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 18 * CENT);  // we should get 18 in 1 coin

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U); // because in the event of a tie, the biggest coin wins


        // now try making 11 cents.  we should get 5+6

        BOOST_CHECK(KnapsackSolver(11 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 11 * CENT);

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);


        // check that the smallest bigger coin is used

        add_coin(coins, *wallet,  1*COIN);

        add_coin(coins, *wallet,  2*COIN);

        add_coin(coins, *wallet,  3*COIN);

        add_coin(coins, *wallet,  4*COIN); // now we have 5+6+7+8+18+20+30+100+200+300+400 = 1094 cents

        BOOST_CHECK(KnapsackSolver(95 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 1 * COIN);  // we should get 1 BTC in 1 coin

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);


        BOOST_CHECK(KnapsackSolver(195 * CENT, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 2 * COIN);  // we should get 2 BTC in 1 coin

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);


        // empty the wallet and start again, now with fractions of a cent, to test small change avoidance


        coins.clear();

        add_coin(coins, *wallet, MIN_CHANGE * 1 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 2 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 3 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 4 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 5 / 10);


        // try making 1 * MIN_CHANGE from the 1.5 * MIN_CHANGE

        // we'll get change smaller than MIN_CHANGE whatever happens, so can expect MIN_CHANGE exactly

        BOOST_CHECK(KnapsackSolver(MIN_CHANGE, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE);


        // but if we add a bigger coin, small change is avoided

        add_coin(coins, *wallet, 1111*MIN_CHANGE);


        // try making 1 from 0.1 + 0.2 + 0.3 + 0.4 + 0.5 + 1111 = 1112.5

        BOOST_CHECK(KnapsackSolver(1 * MIN_CHANGE, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 1 * MIN_CHANGE); // we should get the exact amount


        // if we add more small coins:

        add_coin(coins, *wallet, MIN_CHANGE * 6 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 7 / 10);


        // and try again to make 1.0 * MIN_CHANGE

        BOOST_CHECK(KnapsackSolver(1 * MIN_CHANGE, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 1 * MIN_CHANGE); // we should get the exact amount


        // run the 'mtgox' test (see https://blockexplorer.com/tx/29a3efd3ef04f9153d47a990bd7b048a4b2d213daaa5fb8ed670fb85f13bdbcf)

        // they tried to consolidate 10 50k coins into one 500k coin, and ended up with 50k in change

        coins.clear();

        for (int j = 0; j < 20; j++)

            add_coin(coins, *wallet, 50000 * COIN);


        BOOST_CHECK(KnapsackSolver(500000 * COIN, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 500000 * COIN); // we should get the exact amount

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 10U); // in ten coins


        // if there's not enough in the smaller coins to make at least 1 * MIN_CHANGE change (0.5+0.6+0.7 < 1.0+1.0),

        // we need to try finding an exact subset anyway


        // sometimes it will fail, and so we use the next biggest coin:

        coins.clear();

        add_coin(coins, *wallet, MIN_CHANGE * 5 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 6 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 7 / 10);

        add_coin(coins, *wallet, 1111 * MIN_CHANGE);

        BOOST_CHECK(KnapsackSolver(1 * MIN_CHANGE, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 1111 * MIN_CHANGE); // we get the bigger coin

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);


        // but sometimes it's possible, and we use an exact subset (0.4 + 0.6 = 1.0)

        coins.clear();

        add_coin(coins, *wallet, MIN_CHANGE * 4 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 6 / 10);

        add_coin(coins, *wallet, MIN_CHANGE * 8 / 10);

        add_coin(coins, *wallet, 1111 * MIN_CHANGE);

        BOOST_CHECK(KnapsackSolver(MIN_CHANGE, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE);   // we should get the exact amount

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U); // in two coins 0.4+0.6


        // test avoiding small change

        coins.clear();

        add_coin(coins, *wallet, MIN_CHANGE * 5 / 100);

        add_coin(coins, *wallet, MIN_CHANGE * 1);

        add_coin(coins, *wallet, MIN_CHANGE * 100);


        // trying to make 100.01 from these three coins

        BOOST_CHECK(KnapsackSolver(MIN_CHANGE * 10001 / 100, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE * 10105 / 100); // we should get all coins

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);


        // but if we try to make 99.9, we should take the bigger of the two small coins to avoid small change

        BOOST_CHECK(KnapsackSolver(MIN_CHANGE * 9990 / 100, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));

        BOOST_CHECK_EQUAL(nValueRet, 101 * MIN_CHANGE);

        BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);

    }


    // test with many inputs

    for (CAmount amt=1500; amt < COIN; amt*=10) {

        coins.clear();

        // Create 676 inputs (=  (old MAX_STANDARD_TX_SIZE == 100000)  / 148 bytes per input)

        for (uint16_t j = 0; j < 676; j++)

            add_coin(coins, *wallet, amt);


        // We only create the wallet once to save time, but we still run the coin selection RUN_TESTS times.

        for (int i = 0; i < RUN_TESTS; i++) {

            BOOST_CHECK(KnapsackSolver(2000, KnapsackGroupOutputs(coins, *wallet, filter_confirmed), setCoinsRet, nValueRet));


            if (amt - 2000 < MIN_CHANGE) {

                // needs more than one input:

                uint16_t returnSize = std::ceil((2000.0 + MIN_CHANGE)/amt);

                CAmount returnValue = amt * returnSize;

                BOOST_CHECK_EQUAL(nValueRet, returnValue);

                BOOST_CHECK_EQUAL(setCoinsRet.size(), returnSize);

            } else {

                // one input is sufficient:

                BOOST_CHECK_EQUAL(nValueRet, amt);

                BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);

            }

        }

    }


    // test randomness

    {

        coins.clear();

        for (int i2 = 0; i2 < 100; i2++)

            add_coin(coins, *wallet, COIN);


        // Again, we only create the wallet once to save time, but we still run the coin selection RUN_TESTS times.

        for (int i = 0; i < RUN_TESTS; i++) {

            // picking 50 from 100 coins doesn't depend on the shuffle,

            // but does depend on randomness in the stochastic approximation code

            BOOST_CHECK(KnapsackSolver(50 * COIN, GroupCoins(coins), setCoinsRet, nValueRet));

            BOOST_CHECK(KnapsackSolver(50 * COIN, GroupCoins(coins), setCoinsRet2, nValueRet));

            BOOST_CHECK(!equal_sets(setCoinsRet, setCoinsRet2));


            int fails = 0;

            for (int j = 0; j < RANDOM_REPEATS; j++)

            {

                // Test that the KnapsackSolver selects randomly from equivalent coins (same value and same input size).

                // When choosing 1 from 100 identical coins, 1% of the time, this test will choose the same coin twice

                // which will cause it to fail.

                // To avoid that issue, run the test RANDOM_REPEATS times and only complain if all of them fail

                BOOST_CHECK(KnapsackSolver(COIN, GroupCoins(coins), setCoinsRet, nValueRet));

                BOOST_CHECK(KnapsackSolver(COIN, GroupCoins(coins), setCoinsRet2, nValueRet));

                if (equal_sets(setCoinsRet, setCoinsRet2))

                    fails++;

            }

            BOOST_CHECK_NE(fails, RANDOM_REPEATS);

        }


        // add 75 cents in small change.  not enough to make 90 cents,

        // then try making 90 cents.  there are multiple competing "smallest bigger" coins,

        // one of which should be picked at random

        add_coin(coins, *wallet, 5 * CENT);

        add_coin(coins, *wallet, 10 * CENT);

        add_coin(coins, *wallet, 15 * CENT);

        add_coin(coins, *wallet, 20 * CENT);

        add_coin(coins, *wallet, 25 * CENT);


        for (int i = 0; i < RUN_TESTS; i++) {

            int fails = 0;

            for (int j = 0; j < RANDOM_REPEATS; j++)

            {

                BOOST_CHECK(KnapsackSolver(90*CENT, GroupCoins(coins), setCoinsRet, nValueRet));

                BOOST_CHECK(KnapsackSolver(90*CENT, GroupCoins(coins), setCoinsRet2, nValueRet));

                if (equal_sets(setCoinsRet, setCoinsRet2))

                    fails++;

            }

            BOOST_CHECK_NE(fails, RANDOM_REPEATS);

        }

    }

}


BOOST_AUTO_TEST_CASE(ApproximateBestSubset)

{

    std::unique_ptr<CWallet> wallet = std::make_unique<CWallet>(m_node.chain.get(), "", CreateMockWalletDatabase());

    wallet->LoadWallet();

    LOCK(wallet->cs_wallet);

    wallet->SetWalletFlag(WALLET_FLAG_DESCRIPTORS);

    wallet->SetupDescriptorScriptPubKeyMans();


    CoinSet setCoinsRet;

    CAmount nValueRet;

    std::vector<COutput> coins;


    // Test vValue sort order

    for (int i = 0; i < 1000; i++)

        add_coin(coins, *wallet, 1000 * COIN);

    add_coin(coins, *wallet, 3 * COIN);


    BOOST_CHECK(KnapsackSolver(1003 * COIN, KnapsackGroupOutputs(coins, *wallet, filter_standard), setCoinsRet, nValueRet));

    BOOST_CHECK_EQUAL(nValueRet, 1003 * COIN);

    BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);

}


// Tests that with the ideal conditions, the coin selector will always be able to find a solution that can pay the target value

BOOST_AUTO_TEST_CASE(SelectCoins_test)

{

    std::unique_ptr<CWallet> wallet = std::make_unique<CWallet>(m_node.chain.get(), "", CreateMockWalletDatabase());

    wallet->LoadWallet();

    LOCK(wallet->cs_wallet);

    wallet->SetWalletFlag(WALLET_FLAG_DESCRIPTORS);

    wallet->SetupDescriptorScriptPubKeyMans();


    // Random generator stuff

    std::default_random_engine generator;

    std::exponential_distribution<double> distribution (100);

    FastRandomContext rand;


    // Run this test 100 times

    for (int i = 0; i < 100; ++i)

    {

        std::vector<COutput> coins;

        CAmount balance{0};


        // Make a wallet with 1000 exponentially distributed random inputs

        for (int j = 0; j < 1000; ++j)

        {

            CAmount val = distribution(generator)*10000000;

            add_coin(coins, *wallet, val);

            balance += val;

        }


        // Generate a random fee rate in the range of 100 - 400

        CFeeRate rate(rand.randrange(300) + 100);


        // Generate a random target value between 1000 and wallet balance

        CAmount target = rand.randrange(balance - 1000) + 1000;


        // Perform selection

        CoinSelectionParams cs_params(/* change_output_size= */ 34,

                                      /* change_spend_size= */ 148, /* effective_feerate= */ CFeeRate(0),

                                      /* long_term_feerate= */ CFeeRate(0), /* discard_feerate= */ CFeeRate(0),

                                      /* tx_noinputs_size= */ 0, /* avoid_partial= */ false);

        CoinSet out_set;

        CAmount out_value = 0;

        CCoinControl cc;

        BOOST_CHECK(SelectCoins(*wallet, coins, target, out_set, out_value, cc, cs_params));

        BOOST_CHECK_GE(out_value, target);

    }

}


BOOST_AUTO_TEST_CASE(waste_test)

{

    CoinSet selection;

    const CAmount fee{100};

    const CAmount change_cost{125};

    const CAmount fee_diff{40};

    const CAmount in_amt{3 * COIN};

    const CAmount target{2 * COIN};

    const CAmount excess{in_amt - fee * 2 - target};


    // Waste with change is the change cost and difference between fee and long term fee

    add_coin(1 * COIN, 1, selection, fee, fee - fee_diff);

    add_coin(2 * COIN, 2, selection, fee, fee - fee_diff);

    const CAmount waste1 = GetSelectionWaste(selection, change_cost, target);

    BOOST_CHECK_EQUAL(fee_diff * 2 + change_cost, waste1);

    selection.clear();


    // Waste without change is the excess and difference between fee and long term fee

    add_coin(1 * COIN, 1, selection, fee, fee - fee_diff);

    add_coin(2 * COIN, 2, selection, fee, fee - fee_diff);

    const CAmount waste_nochange1 = GetSelectionWaste(selection, 0, target);

    BOOST_CHECK_EQUAL(fee_diff * 2 + excess, waste_nochange1);

    selection.clear();


    // Waste with change and fee == long term fee is just cost of change

    add_coin(1 * COIN, 1, selection, fee, fee);

    add_coin(2 * COIN, 2, selection, fee, fee);

    BOOST_CHECK_EQUAL(change_cost, GetSelectionWaste(selection, change_cost, target));

    selection.clear();


    // Waste without change and fee == long term fee is just the excess

    add_coin(1 * COIN, 1, selection, fee, fee);

    add_coin(2 * COIN, 2, selection, fee, fee);

    BOOST_CHECK_EQUAL(excess, GetSelectionWaste(selection, 0, target));

    selection.clear();


    // Waste will be greater when fee is greater, but long term fee is the same

    add_coin(1 * COIN, 1, selection, fee * 2, fee - fee_diff);

    add_coin(2 * COIN, 2, selection, fee * 2, fee - fee_diff);

    const CAmount waste2 = GetSelectionWaste(selection, change_cost, target);

    BOOST_CHECK_GT(waste2, waste1);

    selection.clear();


    // Waste with change is the change cost and difference between fee and long term fee

    // With long term fee greater than fee, waste should be less than when long term fee is less than fee

    add_coin(1 * COIN, 1, selection, fee, fee + fee_diff);

    add_coin(2 * COIN, 2, selection, fee, fee + fee_diff);

    const CAmount waste3 = GetSelectionWaste(selection, change_cost, target);

    BOOST_CHECK_EQUAL(fee_diff * -2 + change_cost, waste3);

    BOOST_CHECK_LT(waste3, waste1);

    selection.clear();


    // Waste without change is the excess and difference between fee and long term fee

    // With long term fee greater than fee, waste should be less than when long term fee is less than fee

    add_coin(1 * COIN, 1, selection, fee, fee + fee_diff);

    add_coin(2 * COIN, 2, selection, fee, fee + fee_diff);

    const CAmount waste_nochange2 = GetSelectionWaste(selection, 0, target);

    BOOST_CHECK_EQUAL(fee_diff * -2 + excess, waste_nochange2);

    BOOST_CHECK_LT(waste_nochange2, waste_nochange1);

    selection.clear();


    // No Waste when fee == long_term_fee, no change, and no excess

    add_coin(1 * COIN, 1, selection, fee, fee);

    add_coin(2 * COIN, 2, selection, fee, fee);

    const CAmount exact_target{in_amt - fee * 2};

    BOOST_CHECK_EQUAL(0, GetSelectionWaste(selection, /* change_cost */ 0, exact_target));

    selection.clear();


    // No Waste when (fee - long_term_fee) == (-cost_of_change), and no excess

    const CAmount new_change_cost{fee_diff * 2};

    add_coin(1 * COIN, 1, selection, fee, fee + fee_diff);

    add_coin(2 * COIN, 2, selection, fee, fee + fee_diff);

    BOOST_CHECK_EQUAL(0, GetSelectionWaste(selection, new_change_cost, target));

    selection.clear();


    // No Waste when (fee - long_term_fee) == (-excess), no change cost

    const CAmount new_target{in_amt - fee * 2 - fee_diff * 2};

    add_coin(1 * COIN, 1, selection, fee, fee + fee_diff);

    add_coin(2 * COIN, 2, selection, fee, fee + fee_diff);

    BOOST_CHECK_EQUAL(0, GetSelectionWaste(selection, /* change cost */ 0, new_target));

}


BOOST_AUTO_TEST_SUITE_END()

amount.h

CAmount
int64_t CAmount
Amount in satoshis (Can be negative)
Definition: amount.h:12

COIN
static constexpr CAmount COIN
The amount of satoshis in one BTC.
Definition: amount.h:15

m_node
NodeContext m_node
Definition: bitcoin-gui.cpp:36

CCoinControl
Coin Control Features.
Definition: coincontrol.h:29

CCoinControl::Select
void Select(const COutPoint &output)
Definition: coincontrol.h:91

CCoinControl::fAllowOtherInputs
bool fAllowOtherInputs
If false, allows unselected inputs, but requires all selected inputs be used.
Definition: coincontrol.h:40

CFeeRate
Fee rate in satoshis per kilobyte: CAmount / kB.
Definition: feerate.h:30

CInputCoin
A UTXO under consideration for use in funding a new transaction.
Definition: coinselection.h:21

CInputCoin::m_fee
CAmount m_fee
Definition: coinselection.h:55

CInputCoin::m_long_term_fee
CAmount m_long_term_fee
Definition: coinselection.h:56

CInputCoin::effective_value
CAmount effective_value
Definition: coinselection.h:54

COutPoint
An outpoint - a combination of a transaction hash and an index n into its vout.
Definition: transaction.h:27

COutput
Definition: spend.h:17

CWallet
A CWallet maintains a set of transactions and balances, and provides the ability to create new transa...
Definition: wallet.h:229

CWalletTx
A transaction with a bunch of additional info that only the owner cares about.
Definition: transaction.h:47

CWalletTx::DEBIT
@ DEBIT
Definition: transaction.h:104

CWalletTx::m_amounts
CachableAmount m_amounts[AMOUNTTYPE_ENUM_ELEMENTS]
Definition: transaction.h:105

CWalletTx::m_is_cache_empty
bool m_is_cache_empty
This flag is true if all m_amounts caches are empty.
Definition: transaction.h:112

FastRandomContext
Fast randomness source.
Definition: random.h:120

FastRandomContext::randrange
uint64_t randrange(uint64_t range) noexcept
Generate a random integer in the range [0..range).
Definition: random.h:190

uint256
256-bit opaque blob.
Definition: uint256.h:124

CoinSet
std::set< CInputCoin > CoinSet
Definition: coin_selection.cpp:66

coincontrol.h

KnapsackSolver
bool KnapsackSolver(const CAmount &nTargetValue, std::vector< OutputGroup > &groups, std::set< CInputCoin > &setCoinsRet, CAmount &nValueRet)
Definition: coinselection.cpp:244

SelectCoinsBnB
bool SelectCoinsBnB(std::vector< OutputGroup > &utxo_pool, const CAmount &selection_target, const CAmount &cost_of_change, std::set< CInputCoin > &out_set, CAmount &value_ret)
Definition: coinselection.cpp:67

ApproximateBestSubset
static void ApproximateBestSubset(const std::vector< OutputGroup > &groups, const CAmount &nTotalLower, const CAmount &nTargetValue, std::vector< char > &vfBest, CAmount &nBest, int iterations=1000)
Definition: coinselection.cpp:198

GetSelectionWaste
CAmount GetSelectionWaste(const std::set< CInputCoin > &inputs, CAmount change_cost, CAmount target, bool use_effective_value)
Compute the waste for this result given the cost of change and the opportunity cost of spending these...
Definition: coinselection.cpp:372

coinselection.h

MIN_CHANGE
static constexpr CAmount MIN_CHANGE
target minimum change amount
Definition: coinselection.h:16

filter_standard
static const CoinEligibilityFilter filter_standard(1, 6, 0)

KnapsackGroupOutputs
std::vector< OutputGroup > & KnapsackGroupOutputs(const std::vector< COutput > &coins, CWallet &wallet, const CoinEligibilityFilter &filter)
Definition: coinselector_tests.cpp:129

add_coin
static void add_coin(const CAmount &nValue, int nInput, std::vector< CInputCoin > &set)
Definition: coinselector_tests.cpp:35

make_hard_case
static CAmount make_hard_case(int utxos, std::vector< CInputCoin > &utxo_pool)
Definition: coinselector_tests.cpp:95

BOOST_AUTO_TEST_CASE
BOOST_AUTO_TEST_CASE(bnb_search_test)
Definition: coinselector_tests.cpp:141

filter_confirmed
static const CoinEligibilityFilter filter_confirmed(1, 1, 0)

equal_sets
static bool equal_sets(CoinSet a, CoinSet b)
Definition: coinselector_tests.cpp:89

CoinSet
std::set< CInputCoin > CoinSet
Definition: coinselector_tests.cpp:29

GroupCoins
std::vector< OutputGroup > & GroupCoins(const std::vector< CInputCoin > &coins)
Definition: coinselector_tests.cpp:107

filter_standard_extra
static const CoinEligibilityFilter filter_standard_extra(6, 6, 0)

RANDOM_REPEATS
#define RANDOM_REPEATS
Definition: coinselector_tests.cpp:27

RUN_TESTS
#define RUN_TESTS
Definition: coinselector_tests.cpp:23

BOOST_AUTO_TEST_SUITE_END
BOOST_AUTO_TEST_SUITE_END()

ISMINE_SPENDABLE
@ ISMINE_SPENDABLE
Definition: ismine.h:42

wallet
Definition: interfaces.cpp:50

context.h

BOOST_FIXTURE_TEST_SUITE
#define BOOST_FIXTURE_TEST_SUITE(a, b)
Definition: object.cpp:14

BOOST_CHECK_EQUAL
#define BOOST_CHECK_EQUAL(v1, v2)
Definition: object.cpp:18

BOOST_CHECK
#define BOOST_CHECK(expr)
Definition: object.cpp:17

OutputType::BECH32
@ BECH32

transaction.h

MakeTransactionRef
static CTransactionRef MakeTransactionRef(Tx &&txIn)
Definition: transaction.h:387

random.h

setup_common.h

CENT
static constexpr CAmount CENT
Definition: setup_common.h:71

GroupOutputs
std::vector< OutputGroup > GroupOutputs(const CWallet &wallet, const std::vector< COutput > &outputs, const CoinSelectionParams &coin_sel_params, const CoinEligibilityFilter &filter, bool positive_only)
Definition: spend.cpp:290

SelectCoins
bool SelectCoins(const CWallet &wallet, const std::vector< COutput > &vAvailableCoins, const CAmount &nTargetValue, std::set< CInputCoin > &setCoinsRet, CAmount &nValueRet, const CCoinControl &coin_control, CoinSelectionParams &coin_selection_params)
Select a set of coins such that nValueRet >= nTargetValue and at least all coins from coin_control ar...
Definition: spend.cpp:430

spend.h

GetScriptForDestination
CScript GetScriptForDestination(const CTxDestination &dest)
Generate a Bitcoin scriptPubKey for the given CTxDestination.
Definition: standard.cpp:310

CTxDestination
std::variant< CNoDestination, PKHash, ScriptHash, WitnessV0ScriptHash, WitnessV0KeyHash, WitnessV1Taproot, WitnessUnknown > CTxDestination
A txout script template with a specific destination.
Definition: standard.h:157

CMutableTransaction
A mutable version of CTransaction.
Definition: transaction.h:345

CMutableTransaction::GetHash
uint256 GetHash() const
Compute the hash of this CMutableTransaction.
Definition: transaction.cpp:63

CMutableTransaction::vout
std::vector< CTxOut > vout
Definition: transaction.h:347

CMutableTransaction::vin
std::vector< CTxIn > vin
Definition: transaction.h:346

CMutableTransaction::nLockTime
uint32_t nLockTime
Definition: transaction.h:349

CachableAmount::Set
void Set(isminefilter filter, CAmount value)
Definition: ismine.h:63

CoinEligibilityFilter
Parameters for filtering which OutputGroups we may use in coin selection.
Definition: coinselection.h:119

CoinSelectionParams
Parameters for one iteration of Coin Selection.
Definition: coinselection.h:76

CoinSelectionParams::m_subtract_fee_outputs
bool m_subtract_fee_outputs
Indicate that we are subtracting the fee from outputs.
Definition: coinselection.h:96

CoinSelectionParams::m_cost_of_change
CAmount m_cost_of_change
Cost of creating the change output + cost of spending the change output in the future.
Definition: coinselection.h:84

CoinSelectionParams::m_effective_feerate
CFeeRate m_effective_feerate
The targeted feerate of the transaction being built.
Definition: coinselection.h:86

NodeContext::chain
std::unique_ptr< interfaces::Chain > chain
Definition: context.h:50

WalletTestingSetup
Testing setup and teardown for wallet.
Definition: wallet_test_fixture.h:20

bilingual_str
Bilingual messages:
Definition: translation.h:16

LOCK
#define LOCK(cs)
Definition: sync.h:226

error
bool error(const char *fmt, const Args &... args)
Definition: system.h:49

translation.h

assert
assert(!tx.IsCoinBase())

wallet.h

wallet_test_fixture.h

CreateMockWalletDatabase
std::unique_ptr< WalletDatabase > CreateMockWalletDatabase()
Return object for accessing temporary in-memory database.
Definition: walletdb.cpp:1189

WALLET_FLAG_DESCRIPTORS
@ WALLET_FLAG_DESCRIPTORS
Indicate that this wallet supports DescriptorScriptPubKeyMan.
Definition: walletutil.h:65