1 // Copyright (c) 2012-2015 The Bitcoin Core developers
2 // Distributed under the MIT software license, see the accompanying
3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5 #include "wallet/wallet.h"
6
7 #include <set>
8 #include <stdint.h>
9 #include <utility>
10 #include <vector>
11
12 #include "wallet/test/wallet_test_fixture.h"
13
14 #include <boost/foreach.hpp>
15 #include <boost/test/unit_test.hpp>
16
17 // how many times to run all the tests to have a chance to catch errors that only show up with particular random shuffles
18 #define RUN_TESTS 100
19
20 // some tests fail 1% of the time due to bad luck.
21 // we repeat those tests this many times and only complain if all iterations of the test fail
22 #define RANDOM_REPEATS 5
23
24 using namespace std;
25
26 typedef set<pair<const CWalletTx*,unsigned int> > CoinSet;
27
28 BOOST_FIXTURE_TEST_SUITE(wallet_tests, WalletTestingSetup)
29
30 static const CWallet wallet;
31 static vector<COutput> vCoins;
32
add_coin(const CAmount & nValue,int nAge=6* 24,bool fIsFromMe=false,int nInput=0)33 static void add_coin(const CAmount& nValue, int nAge = 6*24, bool fIsFromMe = false, int nInput=0)
34 {
35 static int nextLockTime = 0;
36 CMutableTransaction tx;
37 tx.nLockTime = nextLockTime++; // so all transactions get different hashes
38 tx.vout.resize(nInput+1);
39 tx.vout[nInput].nValue = nValue;
40 if (fIsFromMe) {
41 // IsFromMe() returns (GetDebit() > 0), and GetDebit() is 0 if vin.empty(),
42 // so stop vin being empty, and cache a non-zero Debit to fake out IsFromMe()
43 tx.vin.resize(1);
44 }
45 CWalletTx* wtx = new CWalletTx(&wallet, tx);
46 if (fIsFromMe)
47 {
48 wtx->fDebitCached = true;
49 wtx->nDebitCached = 1;
50 }
51 COutput output(wtx, nInput, nAge, true, true);
52 vCoins.push_back(output);
53 }
54
empty_wallet(void)55 static void empty_wallet(void)
56 {
57 BOOST_FOREACH(COutput output, vCoins)
58 delete output.tx;
59 vCoins.clear();
60 }
61
equal_sets(CoinSet a,CoinSet b)62 static bool equal_sets(CoinSet a, CoinSet b)
63 {
64 pair<CoinSet::iterator, CoinSet::iterator> ret = mismatch(a.begin(), a.end(), b.begin());
65 return ret.first == a.end() && ret.second == b.end();
66 }
67
BOOST_AUTO_TEST_CASE(coin_selection_tests)68 BOOST_AUTO_TEST_CASE(coin_selection_tests)
69 {
70 CoinSet setCoinsRet, setCoinsRet2;
71 CAmount nValueRet;
72
73 LOCK(wallet.cs_wallet);
74
75 // test multiple times to allow for differences in the shuffle order
76 for (int i = 0; i < RUN_TESTS; i++)
77 {
78 empty_wallet();
79
80 // with an empty wallet we can't even pay one cent
81 BOOST_CHECK(!wallet.SelectCoinsMinConf( 1 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
82
83 add_coin(1*CENT, 4); // add a new 1 cent coin
84
85 // with a new 1 cent coin, we still can't find a mature 1 cent
86 BOOST_CHECK(!wallet.SelectCoinsMinConf( 1 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
87
88 // but we can find a new 1 cent
89 BOOST_CHECK( wallet.SelectCoinsMinConf( 1 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
90 BOOST_CHECK_EQUAL(nValueRet, 1 * CENT);
91
92 add_coin(2*CENT); // add a mature 2 cent coin
93
94 // we can't make 3 cents of mature coins
95 BOOST_CHECK(!wallet.SelectCoinsMinConf( 3 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
96
97 // we can make 3 cents of new coins
98 BOOST_CHECK( wallet.SelectCoinsMinConf( 3 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
99 BOOST_CHECK_EQUAL(nValueRet, 3 * CENT);
100
101 add_coin(5*CENT); // add a mature 5 cent coin,
102 add_coin(10*CENT, 3, true); // a new 10 cent coin sent from one of our own addresses
103 add_coin(20*CENT); // and a mature 20 cent coin
104
105 // now we have new: 1+10=11 (of which 10 was self-sent), and mature: 2+5+20=27. total = 38
106
107 // we can't make 38 cents only if we disallow new coins:
108 BOOST_CHECK(!wallet.SelectCoinsMinConf(38 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
109 // we can't even make 37 cents if we don't allow new coins even if they're from us
110 BOOST_CHECK(!wallet.SelectCoinsMinConf(38 * CENT, 6, 6, 0, vCoins, setCoinsRet, nValueRet));
111 // but we can make 37 cents if we accept new coins from ourself
112 BOOST_CHECK( wallet.SelectCoinsMinConf(37 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
113 BOOST_CHECK_EQUAL(nValueRet, 37 * CENT);
114 // and we can make 38 cents if we accept all new coins
115 BOOST_CHECK( wallet.SelectCoinsMinConf(38 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
116 BOOST_CHECK_EQUAL(nValueRet, 38 * CENT);
117
118 // try making 34 cents from 1,2,5,10,20 - we can't do it exactly
119 BOOST_CHECK( wallet.SelectCoinsMinConf(34 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
120 BOOST_CHECK_EQUAL(nValueRet, 35 * CENT); // but 35 cents is closest
121 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)
122
123 // when we try making 7 cents, the smaller coins (1,2,5) are enough. We should see just 2+5
124 BOOST_CHECK( wallet.SelectCoinsMinConf( 7 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
125 BOOST_CHECK_EQUAL(nValueRet, 7 * CENT);
126 BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);
127
128 // when we try making 8 cents, the smaller coins (1,2,5) are exactly enough.
129 BOOST_CHECK( wallet.SelectCoinsMinConf( 8 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
130 BOOST_CHECK(nValueRet == 8 * CENT);
131 BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);
132
133 // when we try making 9 cents, no subset of smaller coins is enough, and we get the next bigger coin (10)
134 BOOST_CHECK( wallet.SelectCoinsMinConf( 9 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
135 BOOST_CHECK_EQUAL(nValueRet, 10 * CENT);
136 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
137
138 // now clear out the wallet and start again to test choosing between subsets of smaller coins and the next biggest coin
139 empty_wallet();
140
141 add_coin( 6*CENT);
142 add_coin( 7*CENT);
143 add_coin( 8*CENT);
144 add_coin(20*CENT);
145 add_coin(30*CENT); // now we have 6+7+8+20+30 = 71 cents total
146
147 // check that we have 71 and not 72
148 BOOST_CHECK( wallet.SelectCoinsMinConf(71 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
149 BOOST_CHECK(!wallet.SelectCoinsMinConf(72 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
150
151 // 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
152 BOOST_CHECK( wallet.SelectCoinsMinConf(16 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
153 BOOST_CHECK_EQUAL(nValueRet, 20 * CENT); // we should get 20 in one coin
154 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
155
156 add_coin( 5*CENT); // now we have 5+6+7+8+20+30 = 75 cents total
157
158 // 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
159 BOOST_CHECK( wallet.SelectCoinsMinConf(16 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
160 BOOST_CHECK_EQUAL(nValueRet, 18 * CENT); // we should get 18 in 3 coins
161 BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);
162
163 add_coin( 18*CENT); // now we have 5+6+7+8+18+20+30
164
165 // 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
166 BOOST_CHECK( wallet.SelectCoinsMinConf(16 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
167 BOOST_CHECK_EQUAL(nValueRet, 18 * CENT); // we should get 18 in 1 coin
168 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U); // because in the event of a tie, the biggest coin wins
169
170 // now try making 11 cents. we should get 5+6
171 BOOST_CHECK( wallet.SelectCoinsMinConf(11 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
172 BOOST_CHECK_EQUAL(nValueRet, 11 * CENT);
173 BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);
174
175 // check that the smallest bigger coin is used
176 add_coin( 1*COIN);
177 add_coin( 2*COIN);
178 add_coin( 3*COIN);
179 add_coin( 4*COIN); // now we have 5+6+7+8+18+20+30+100+200+300+400 = 1094 cents
180 BOOST_CHECK( wallet.SelectCoinsMinConf(95 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
181 BOOST_CHECK_EQUAL(nValueRet, 1 * COIN); // we should get 1 BTC in 1 coin
182 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
183
184 BOOST_CHECK( wallet.SelectCoinsMinConf(195 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
185 BOOST_CHECK_EQUAL(nValueRet, 2 * COIN); // we should get 2 BTC in 1 coin
186 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
187
188 // empty the wallet and start again, now with fractions of a cent, to test small change avoidance
189
190 empty_wallet();
191 add_coin(MIN_CHANGE * 1 / 10);
192 add_coin(MIN_CHANGE * 2 / 10);
193 add_coin(MIN_CHANGE * 3 / 10);
194 add_coin(MIN_CHANGE * 4 / 10);
195 add_coin(MIN_CHANGE * 5 / 10);
196
197 // try making 1 * MIN_CHANGE from the 1.5 * MIN_CHANGE
198 // we'll get change smaller than MIN_CHANGE whatever happens, so can expect MIN_CHANGE exactly
199 BOOST_CHECK( wallet.SelectCoinsMinConf(MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
200 BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE);
201
202 // but if we add a bigger coin, small change is avoided
203 add_coin(1111*MIN_CHANGE);
204
205 // try making 1 from 0.1 + 0.2 + 0.3 + 0.4 + 0.5 + 1111 = 1112.5
206 BOOST_CHECK( wallet.SelectCoinsMinConf(1 * MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
207 BOOST_CHECK_EQUAL(nValueRet, 1 * MIN_CHANGE); // we should get the exact amount
208
209 // if we add more small coins:
210 add_coin(MIN_CHANGE * 6 / 10);
211 add_coin(MIN_CHANGE * 7 / 10);
212
213 // and try again to make 1.0 * MIN_CHANGE
214 BOOST_CHECK( wallet.SelectCoinsMinConf(1 * MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
215 BOOST_CHECK_EQUAL(nValueRet, 1 * MIN_CHANGE); // we should get the exact amount
216
217 // run the 'mtgox' test (see http://blockexplorer.com/tx/29a3efd3ef04f9153d47a990bd7b048a4b2d213daaa5fb8ed670fb85f13bdbcf)
218 // they tried to consolidate 10 50k coins into one 500k coin, and ended up with 50k in change
219 empty_wallet();
220 for (int i = 0; i < 20; i++)
221 add_coin(50000 * COIN);
222
223 BOOST_CHECK( wallet.SelectCoinsMinConf(500000 * COIN, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
224 BOOST_CHECK_EQUAL(nValueRet, 500000 * COIN); // we should get the exact amount
225 BOOST_CHECK_EQUAL(setCoinsRet.size(), 10U); // in ten coins
226
227 // 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),
228 // we need to try finding an exact subset anyway
229
230 // sometimes it will fail, and so we use the next biggest coin:
231 empty_wallet();
232 add_coin(MIN_CHANGE * 5 / 10);
233 add_coin(MIN_CHANGE * 6 / 10);
234 add_coin(MIN_CHANGE * 7 / 10);
235 add_coin(1111 * MIN_CHANGE);
236 BOOST_CHECK( wallet.SelectCoinsMinConf(1 * MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
237 BOOST_CHECK_EQUAL(nValueRet, 1111 * MIN_CHANGE); // we get the bigger coin
238 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
239
240 // but sometimes it's possible, and we use an exact subset (0.4 + 0.6 = 1.0)
241 empty_wallet();
242 add_coin(MIN_CHANGE * 4 / 10);
243 add_coin(MIN_CHANGE * 6 / 10);
244 add_coin(MIN_CHANGE * 8 / 10);
245 add_coin(1111 * MIN_CHANGE);
246 BOOST_CHECK( wallet.SelectCoinsMinConf(MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
247 BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE); // we should get the exact amount
248 BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U); // in two coins 0.4+0.6
249
250 // test avoiding small change
251 empty_wallet();
252 add_coin(MIN_CHANGE * 5 / 100);
253 add_coin(MIN_CHANGE * 1);
254 add_coin(MIN_CHANGE * 100);
255
256 // trying to make 100.01 from these three coins
257 BOOST_CHECK(wallet.SelectCoinsMinConf(MIN_CHANGE * 10001 / 100, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
258 BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE * 10105 / 100); // we should get all coins
259 BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);
260
261 // but if we try to make 99.9, we should take the bigger of the two small coins to avoid small change
262 BOOST_CHECK(wallet.SelectCoinsMinConf(MIN_CHANGE * 9990 / 100, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
263 BOOST_CHECK_EQUAL(nValueRet, 101 * MIN_CHANGE);
264 BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);
265
266 // test with many inputs
267 for (CAmount amt=1500; amt < COIN; amt*=10) {
268 empty_wallet();
269 // Create 676 inputs (= MAX_STANDARD_TX_SIZE / 148 bytes per input)
270 for (uint16_t j = 0; j < 676; j++)
271 add_coin(amt);
272 BOOST_CHECK(wallet.SelectCoinsMinConf(2000, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
273 if (amt - 2000 < MIN_CHANGE) {
274 // needs more than one input:
275 uint16_t returnSize = std::ceil((2000.0 + MIN_CHANGE)/amt);
276 CAmount returnValue = amt * returnSize;
277 BOOST_CHECK_EQUAL(nValueRet, returnValue);
278 BOOST_CHECK_EQUAL(setCoinsRet.size(), returnSize);
279 } else {
280 // one input is sufficient:
281 BOOST_CHECK_EQUAL(nValueRet, amt);
282 BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
283 }
284 }
285
286 // test randomness
287 {
288 empty_wallet();
289 for (int i2 = 0; i2 < 100; i2++)
290 add_coin(COIN);
291
292 // picking 50 from 100 coins doesn't depend on the shuffle,
293 // but does depend on randomness in the stochastic approximation code
294 BOOST_CHECK(wallet.SelectCoinsMinConf(50 * COIN, 1, 6, 0, vCoins, setCoinsRet , nValueRet));
295 BOOST_CHECK(wallet.SelectCoinsMinConf(50 * COIN, 1, 6, 0, vCoins, setCoinsRet2, nValueRet));
296 BOOST_CHECK(!equal_sets(setCoinsRet, setCoinsRet2));
297
298 int fails = 0;
299 for (int i = 0; i < RANDOM_REPEATS; i++)
300 {
301 // selecting 1 from 100 identical coins depends on the shuffle; this test will fail 1% of the time
302 // run the test RANDOM_REPEATS times and only complain if all of them fail
303 BOOST_CHECK(wallet.SelectCoinsMinConf(COIN, 1, 6, 0, vCoins, setCoinsRet , nValueRet));
304 BOOST_CHECK(wallet.SelectCoinsMinConf(COIN, 1, 6, 0, vCoins, setCoinsRet2, nValueRet));
305 if (equal_sets(setCoinsRet, setCoinsRet2))
306 fails++;
307 }
308 BOOST_CHECK_NE(fails, RANDOM_REPEATS);
309
310 // add 75 cents in small change. not enough to make 90 cents,
311 // then try making 90 cents. there are multiple competing "smallest bigger" coins,
312 // one of which should be picked at random
313 add_coin(5 * CENT);
314 add_coin(10 * CENT);
315 add_coin(15 * CENT);
316 add_coin(20 * CENT);
317 add_coin(25 * CENT);
318
319 fails = 0;
320 for (int i = 0; i < RANDOM_REPEATS; i++)
321 {
322 // selecting 1 from 100 identical coins depends on the shuffle; this test will fail 1% of the time
323 // run the test RANDOM_REPEATS times and only complain if all of them fail
324 BOOST_CHECK(wallet.SelectCoinsMinConf(90*CENT, 1, 6, 0, vCoins, setCoinsRet , nValueRet));
325 BOOST_CHECK(wallet.SelectCoinsMinConf(90*CENT, 1, 6, 0, vCoins, setCoinsRet2, nValueRet));
326 if (equal_sets(setCoinsRet, setCoinsRet2))
327 fails++;
328 }
329 BOOST_CHECK_NE(fails, RANDOM_REPEATS);
330 }
331 }
332 empty_wallet();
333 }
334
BOOST_AUTO_TEST_CASE(ApproximateBestSubset)335 BOOST_AUTO_TEST_CASE(ApproximateBestSubset)
336 {
337 CoinSet setCoinsRet;
338 CAmount nValueRet;
339
340 LOCK(wallet.cs_wallet);
341
342 empty_wallet();
343
344 // Test vValue sort order
345 for (int i = 0; i < 1000; i++)
346 add_coin(1000 * COIN);
347 add_coin(3 * COIN);
348
349 BOOST_CHECK(wallet.SelectCoinsMinConf(1003 * COIN, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
350 BOOST_CHECK_EQUAL(nValueRet, 1003 * COIN);
351 BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);
352 }
353
354 BOOST_AUTO_TEST_SUITE_END()
355