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#include <boost/test/unit_test.hpp>
#include "main.h"
#include "wallet.h"
// 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
// enables tests which currently fail, due to code which tries too hard to avoid sub-cent change
// #define STRICT
using namespace std;
BOOST_AUTO_TEST_SUITE(wallet_tests)
static CWallet wallet;
static vector<COutput> vCoins;
static void add_coin(int64 nValue, int nAge = 6*24, bool fIsFromMe = false, int nInput=0)
{
static int i;
CTransaction* tx = new CTransaction;
tx->nLockTime = i++; // so all transactions get different hashes
tx->vout.resize(nInput+1);
tx->vout[nInput].nValue = nValue;
CWalletTx* wtx = new CWalletTx(&wallet, *tx);
delete tx;
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()
wtx->vin.resize(1);
wtx->fDebitCached = true;
wtx->nDebitCached = 1;
}
COutput output(wtx, nInput, nAge);
vCoins.push_back(output);
}
static void empty_wallet(void)
{
BOOST_FOREACH(COutput output, vCoins)
delete output.tx;
vCoins.clear();
}
BOOST_AUTO_TEST_CASE(coin_selection_tests)
{
static set<pair<const CWalletTx*,unsigned int> > setCoinsRet;
static int64 nValueRet;
// test multiple times to allow for differences in the shuffle order
for (int i = 0; i < RUN_TESTS; i++)
{
empty_wallet();
// with an empty wallet we can't even pay one cent
BOOST_CHECK(!wallet.SelectCoinsMinConf( 1 * CENT, 1, 6, vCoins, setCoinsRet, nValueRet));
add_coin(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(!wallet.SelectCoinsMinConf( 1 * CENT, 1, 6, vCoins, setCoinsRet, nValueRet));
// but we can find a new 1 cent
BOOST_CHECK( wallet.SelectCoinsMinConf( 1 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 1 * CENT);
add_coin(2*CENT); // add a mature 2 cent coin
// we can't make 3 cents of mature coins
BOOST_CHECK(!wallet.SelectCoinsMinConf( 3 * CENT, 1, 6, vCoins, setCoinsRet, nValueRet));
// we can make 3 cents of new coins
BOOST_CHECK( wallet.SelectCoinsMinConf( 3 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 3 * CENT);
add_coin(5*CENT); // add a mature 5 cent coin,
add_coin(10*CENT, 3, true); // a new 10 cent coin sent from one of our own addresses
add_coin(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(!wallet.SelectCoinsMinConf(38 * CENT, 1, 6, vCoins, setCoinsRet, nValueRet));
// we can't even make 37 cents if we don't allow new coins even if they're from us
BOOST_CHECK(!wallet.SelectCoinsMinConf(38 * CENT, 6, 6, vCoins, setCoinsRet, nValueRet));
// but we can make 37 cents if we accept new coins from ourself
BOOST_CHECK( wallet.SelectCoinsMinConf(37 * CENT, 1, 6, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 37 * CENT);
// and we can make 38 cents if we accept all new coins
BOOST_CHECK( wallet.SelectCoinsMinConf(38 * CENT, 1, 1, vCoins, 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( wallet.SelectCoinsMinConf(34 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_GT(nValueRet, 34 * CENT); // but should get more than 34 cents
BOOST_CHECK_EQUAL(setCoinsRet.size(), 3); // 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. I'd hope to see just 2+5, but 1 gets included too
BOOST_CHECK( wallet.SelectCoinsMinConf( 7 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
#ifdef STRICT
BOOST_CHECK_EQUAL(nValueRet, 7 * CENT);
BOOST_CHECK_EQUAL(setCoinsRet.size(), 2);
#else
BOOST_CHECK(nValueRet == 7 * CENT || nValueRet == 8 * CENT);
BOOST_CHECK(setCoinsRet.size() == 2 || setCoinsRet.size() == 3);
#endif
// when we try making 8 cents, the smaller coins (1,2,5) are exactly enough.
BOOST_CHECK( wallet.SelectCoinsMinConf( 8 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK(nValueRet == 8 * CENT);
BOOST_CHECK_EQUAL(setCoinsRet.size(), 3);
// when we try making 9 cents, no subset of smaller coins is enough, and we get the next bigger coin (10)
BOOST_CHECK( wallet.SelectCoinsMinConf( 9 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 10 * CENT);
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1);
// now clear out the wallet and start again to test chosing between subsets of smaller coins and the next biggest coin
empty_wallet();
add_coin( 6*CENT);
add_coin( 7*CENT);
add_coin( 8*CENT);
add_coin(20*CENT);
add_coin(30*CENT); // now we have 6+7+8+20+30 = 71 cents total
// check that we have 71 and not 72
BOOST_CHECK( wallet.SelectCoinsMinConf(71 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK(!wallet.SelectCoinsMinConf(72 * CENT, 1, 1, vCoins, 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( wallet.SelectCoinsMinConf(16 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 20 * CENT); // we should get 20 in one coin
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1);
add_coin( 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( wallet.SelectCoinsMinConf(16 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 18 * CENT); // we should get 18 in 3 coins
BOOST_CHECK_EQUAL(setCoinsRet.size(), 3);
add_coin( 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( wallet.SelectCoinsMinConf(16 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 18 * CENT); // we should get 18 in 1 coin
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1); // because in the event of a tie, the biggest coin wins
// now try making 11 cents. we hope for 5+6 but get 5+7 due to fear of sub-cent change
BOOST_CHECK( wallet.SelectCoinsMinConf(11 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
#ifdef STRICT
BOOST_CHECK_EQUAL(nValueRet, 11 * CENT);
#else
BOOST_CHECK(nValueRet == 11 * CENT || nValueRet == 12 * CENT);
#endif
BOOST_CHECK_EQUAL(setCoinsRet.size(), 2);
// check that the smallest bigger coin is used
add_coin( 1*COIN);
add_coin( 2*COIN);
add_coin( 3*COIN);
add_coin( 4*COIN); // now we have 5+6+7+8+18+20+30+100+200+300+400 = 1094 cents
BOOST_CHECK( wallet.SelectCoinsMinConf(95 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 1 * COIN); // we should get 1 bitcoin in 1 coin
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1);
BOOST_CHECK( wallet.SelectCoinsMinConf(195 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 2 * COIN); // we should get 2 bitcoins in 1 coin
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1);
// empty the wallet and start again, now with fractions of a cent, to test sub-cent change avoidance
empty_wallet();
add_coin(0.1*CENT);
add_coin(0.2*CENT);
add_coin(0.3*CENT);
add_coin(0.4*CENT);
add_coin(0.5*CENT);
// try making 1 cent from 0.1 + 0.2 + 0.3 + 0.4 + 0.5 = 1.5 cents
// we'll get sub-cent change whatever happens, so can expect 1.0 exactly
BOOST_CHECK( wallet.SelectCoinsMinConf(1 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 1 * CENT);
// but if we add a bigger coin, making it possible to avoid sub-cent change, things change:
add_coin(1111*CENT);
// try making 1 cent from 0.1 + 0.2 + 0.3 + 0.4 + 0.5 + 1111 = 1112.5 cents
BOOST_CHECK( wallet.SelectCoinsMinConf(1 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
#ifdef STRICT
BOOST_CHECK_EQUAL(nValueRet, 1 * CENT); // we hope for the exact amount
#else
BOOST_CHECK(nValueRet == 1 * CENT || nValueRet == 1111 * CENT); // but get a single 1111 cent coin
#endif
// if we add more sub-cent coins:
add_coin(0.6*CENT);
add_coin(0.7*CENT);
// and try again to make 1.0 cents, the new coins will be used to make 2.0 cents - leaving 1.0 cent change
BOOST_CHECK( wallet.SelectCoinsMinConf(1 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
#ifdef STRICT
BOOST_CHECK_EQUAL(nValueRet, 1 * CENT); // we hope for the exact amount
#else
BOOST_CHECK(nValueRet == 1 * CENT || nValueRet == 2 * CENT); // but get a bunch of sub-cent coins totalling 2 cents
BOOST_CHECK_GE(setCoinsRet.size(), 4); // 0.7 + 0.6 + 0.5 + 0.2 = 2.0 for example
#endif
// run the 'mtgox' test (see http://blockexplorer.com/tx/29a3efd3ef04f9153d47a990bd7b048a4b2d213daaa5fb8ed670fb85f13bdbcf)
// they tried to consolidate 10 50k coins into one 500k coin, and ended up with 50k in change
empty_wallet();
for (int i = 0; i < 20; i++)
add_coin(50000 * COIN);
BOOST_CHECK( wallet.SelectCoinsMinConf(500000 * COIN, 1, 1, vCoins, setCoinsRet, nValueRet));
#ifdef STRICT
BOOST_CHECK_EQUAL(nValueRet, 500000 * COIN); // we hope for the exact amount
BOOST_CHECK_EQUAL(setCoinsRet.size(), 10); // in ten coins
#else
BOOST_CHECK(nValueRet == 500000 * COIN || nValueRet == 550000 * COIN); // but get 50k too much
BOOST_CHECK(setCoinsRet.size() == 10 || setCoinsRet.size() == 11); // in 11 coins
#endif
// if there's not enough in the smaller coins to make at least 1 cent 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:
empty_wallet();
add_coin(0.5 * CENT);
add_coin(0.6 * CENT);
add_coin(0.7 * CENT);
add_coin(1111 * CENT);
BOOST_CHECK( wallet.SelectCoinsMinConf(1 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
BOOST_CHECK_EQUAL(nValueRet, 1111 * CENT); // we get the bigger coin
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1);
// but sometimes it's possible, and we use an exact subset (0.4 + 0.6 = 1.0)
empty_wallet();
add_coin(0.4 * CENT);
add_coin(0.6 * CENT);
add_coin(0.8 * CENT);
add_coin(1111 * CENT);
BOOST_CHECK( wallet.SelectCoinsMinConf(1 * CENT, 1, 1, vCoins, setCoinsRet, nValueRet));
#ifdef STRICT
BOOST_CHECK_EQUAL(nValueRet, 1 * CENT); // we hope for the exact amount
BOOST_CHECK_EQUAL(setCoinsRet.size(), 2); // in two coins 0.4+0.6
#else
BOOST_CHECK_EQUAL(nValueRet, 1111 * CENT); // but since value of smaller coins < target+cent, we get the bigger coin again
BOOST_CHECK_EQUAL(setCoinsRet.size(), 1);
#endif
}
}
BOOST_AUTO_TEST_SUITE_END()
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