text: // Copyright (c) 2012-2016 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 "wallet/wallet.h"
  
  #include <set>
  #include <stdint.h>
  #include <utility>
  #include <vector>
  
  #include "consensus/validation.h"
  #include "rpc/server.h"
  #include "test/test_bitcoin.h"
  #include "validation.h"
  #include "wallet/coincontrol.h"
  #include "wallet/test/wallet_test_fixture.h"
  
  #include <boost/test/unit_test.hpp>
  #include <univalue.h>
  
  extern CWallet* pwalletMain;
  
  extern UniValue importmulti(const JSONRPCRequest& request);
  extern UniValue dumpwallet(const JSONRPCRequest& request);
  extern UniValue importwallet(const JSONRPCRequest& request);
  
  // 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
  
  std::vector<std::unique_ptr<CWalletTx>> wtxn;
  
  typedef std::set<CInputCoin> CoinSet;
  
  BOOST_FIXTURE_TEST_SUITE(wallet_tests, WalletTestingSetup)
  
  static const CWallet testWallet;
  static std::vector<COutput> vCoins;
  
  static void add_coin(const CAmount& nValue, int nAge = 6*24, bool fIsFromMe = false, int nInput=0)
  {
      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 (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);
      }
      std::unique_ptr<CWalletTx> wtx(new CWalletTx(&testWallet, MakeTransactionRef(std::move(tx))));
      if (fIsFromMe)
      {
          wtx->fDebitCached = true;
          wtx->nDebitCached = 1;
      }
      COutput output(wtx.get(), nInput, nAge, true /* spendable */, true /* solvable */, true /* safe */);
      vCoins.push_back(output);
      wtxn.emplace_back(std::move(wtx));
  }
  
  static void empty_wallet(void)
  {
      vCoins.clear();
      wtxn.clear();
  }
  
  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();
  }
  
  BOOST_AUTO_TEST_CASE(coin_selection_tests)
  {
      CoinSet setCoinsRet, setCoinsRet2;
      CAmount nValueRet;
  
      LOCK(testWallet.cs_wallet);
  
      // 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(!testWallet.SelectCoinsMinConf( 1 * CENT, 1, 6, 0, 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(!testWallet.SelectCoinsMinConf( 1 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
  
          // but we can find a new 1 cent
          BOOST_CHECK( testWallet.SelectCoinsMinConf( 1 * CENT, 1, 1, 0, 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(!testWallet.SelectCoinsMinConf( 3 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
  
          // we can make 3 cents of new  coins
          BOOST_CHECK( testWallet.SelectCoinsMinConf( 3 * CENT, 1, 1, 0, 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(!testWallet.SelectCoinsMinConf(38 * CENT, 1, 6, 0, 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(!testWallet.SelectCoinsMinConf(38 * CENT, 6, 6, 0, vCoins, setCoinsRet, nValueRet));
          // but we can make 37 cents if we accept new coins from ourself
          BOOST_CHECK( testWallet.SelectCoinsMinConf(37 * CENT, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 37 * CENT);
          // and we can make 38 cents if we accept all new coins
          BOOST_CHECK( testWallet.SelectCoinsMinConf(38 * CENT, 1, 1, 0, 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( testWallet.SelectCoinsMinConf(34 * CENT, 1, 1, 0, vCoins, 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( testWallet.SelectCoinsMinConf( 7 * CENT, 1, 1, 0, vCoins, 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( testWallet.SelectCoinsMinConf( 8 * CENT, 1, 1, 0, vCoins, 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( testWallet.SelectCoinsMinConf( 9 * CENT, 1, 1, 0, vCoins, 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
          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( testWallet.SelectCoinsMinConf(71 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK(!testWallet.SelectCoinsMinConf(72 * CENT, 1, 1, 0, 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( testWallet.SelectCoinsMinConf(16 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 20 * CENT); // we should get 20 in one coin
          BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
  
          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( testWallet.SelectCoinsMinConf(16 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 18 * CENT); // we should get 18 in 3 coins
          BOOST_CHECK_EQUAL(setCoinsRet.size(), 3U);
  
          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( testWallet.SelectCoinsMinConf(16 * CENT, 1, 1, 0, vCoins, 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( testWallet.SelectCoinsMinConf(11 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 11 * CENT);
          BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);
  
          // 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( testWallet.SelectCoinsMinConf(95 * CENT, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 1 * COIN);  // we should get 1 BTC in 1 coin
          BOOST_CHECK_EQUAL(setCoinsRet.size(), 1U);
  
          BOOST_CHECK( testWallet.SelectCoinsMinConf(195 * CENT, 1, 1, 0, vCoins, 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
  
          empty_wallet();
          add_coin(MIN_CHANGE * 1 / 10);
          add_coin(MIN_CHANGE * 2 / 10);
          add_coin(MIN_CHANGE * 3 / 10);
          add_coin(MIN_CHANGE * 4 / 10);
          add_coin(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( testWallet.SelectCoinsMinConf(MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, MIN_CHANGE);
  
          // but if we add a bigger coin, small change is avoided
          add_coin(1111*MIN_CHANGE);
  
          // try making 1 from 0.1 + 0.2 + 0.3 + 0.4 + 0.5 + 1111 = 1112.5
          BOOST_CHECK( testWallet.SelectCoinsMinConf(1 * MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 1 * MIN_CHANGE); // we should get the exact amount
  
          // if we add more small coins:
          add_coin(MIN_CHANGE * 6 / 10);
          add_coin(MIN_CHANGE * 7 / 10);
  
          // and try again to make 1.0 * MIN_CHANGE
          BOOST_CHECK( testWallet.SelectCoinsMinConf(1 * MIN_CHANGE, 1, 1, 0, vCoins, setCoinsRet, nValueRet));
          BOOST_CHECK_EQUAL(nValueRet, 1 * MIN_CHANGE); // we should get the exact amount
  
          // 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 j = 0; j < 20; j++)
              add_coin(50000 * COIN);
  
          BOOST_CHECK( testWallet.SelectCoinsMinConf(500000 * COIN, 1, 1, 0, vCoins, 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:
          empty_wallet();
          add_coin(MIN_CHANGE * 5 / 10);
          add_coin(MIN_CHANGE * 6 / 10);
          add_coin(MIN_CHANGE * 7 / 10);
          add_coin(1111 * MIN_CHANGE);
          BOOST_CHECK( testWallet.SelectCoinsMinConf(1 * MIN_CHANGE, 1, 1, 0, vCoins, 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)
          empty_wallet();
          add_coin(MIN_CHANGE * 4 / 10);
          add_coin(MIN_CHANGE * 6 / 10);
          add_coin(MIN_CHANGE * 8 / 10);
          add_coin(1111 * MIN_CHANGE);
          BOOST_CHECK( testWallet.SelectCoinsMinConf(MIN_CHANGE, 1, 1, 0, vCoins, 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
          empty_wallet();
          add_coin(MIN_CHANGE * 5 / 100);
          add_coin(MIN_CHANGE * 1);
          add_coin(MIN_CHANGE * 100);
  
          // trying to make 100.01 from these three coins
          BOOST_CHECK(testWallet.SelectCoinsMinConf(MIN_CHANGE * 10001 / 100, 1, 1, 0, vCoins, 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(testWallet.SelectCoinsMinConf(MIN_CHANGE * 9990 / 100, 1, 1, 0, vCoins, 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) {
               empty_wallet();
               // Create 676 inputs (=  (old MAX_STANDARD_TX_SIZE == 100000)  / 148 bytes per input)
               for (uint16_t j = 0; j < 676; j++)
                   add_coin(amt);
               BOOST_CHECK(testWallet.SelectCoinsMinConf(2000, 1, 1, 0, vCoins, 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
          {
              empty_wallet();
              for (int i2 = 0; i2 < 100; i2++)
                  add_coin(COIN);
  
              // picking 50 from 100 coins doesn't depend on the shuffle,
              // but does depend on randomness in the stochastic approximation code
              BOOST_CHECK(testWallet.SelectCoinsMinConf(50 * COIN, 1, 6, 0, vCoins, setCoinsRet , nValueRet));
              BOOST_CHECK(testWallet.SelectCoinsMinConf(50 * COIN, 1, 6, 0, vCoins, setCoinsRet2, nValueRet));
              BOOST_CHECK(!equal_sets(setCoinsRet, setCoinsRet2));
  
              int fails = 0;
              for (int j = 0; j < RANDOM_REPEATS; j++)
              {
                  // selecting 1 from 100 identical coins depends on the shuffle; this test will fail 1% of the time
                  // run the test RANDOM_REPEATS times and only complain if all of them fail
                  BOOST_CHECK(testWallet.SelectCoinsMinConf(COIN, 1, 6, 0, vCoins, setCoinsRet , nValueRet));
                  BOOST_CHECK(testWallet.SelectCoinsMinConf(COIN, 1, 6, 0, vCoins, 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(5 * CENT);
              add_coin(10 * CENT);
              add_coin(15 * CENT);
              add_coin(20 * CENT);
              add_coin(25 * CENT);
  
              fails = 0;
              for (int j = 0; j < RANDOM_REPEATS; j++)
              {
                  // selecting 1 from 100 identical coins depends on the shuffle; this test will fail 1% of the time
                  // run the test RANDOM_REPEATS times and only complain if all of them fail
                  BOOST_CHECK(testWallet.SelectCoinsMinConf(90*CENT, 1, 6, 0, vCoins, setCoinsRet , nValueRet));
                  BOOST_CHECK(testWallet.SelectCoinsMinConf(90*CENT, 1, 6, 0, vCoins, setCoinsRet2, nValueRet));
                  if (equal_sets(setCoinsRet, setCoinsRet2))
                      fails++;
              }
              BOOST_CHECK_NE(fails, RANDOM_REPEATS);
          }
      }
      empty_wallet();
  }
  
  BOOST_AUTO_TEST_CASE(ApproximateBestSubset)
  {
      CoinSet setCoinsRet;
      CAmount nValueRet;
  
      LOCK(testWallet.cs_wallet);
  
      empty_wallet();
  
      // Test vValue sort order
      for (int i = 0; i < 1000; i++)
          add_coin(1000 * COIN);
      add_coin(3 * COIN);
  
      BOOST_CHECK(testWallet.SelectCoinsMinConf(1003 * COIN, 1, 6, 0, vCoins, setCoinsRet, nValueRet));
      BOOST_CHECK_EQUAL(nValueRet, 1003 * COIN);
      BOOST_CHECK_EQUAL(setCoinsRet.size(), 2U);
  
      empty_wallet();
  }
  
  static void AddKey(CWallet& wallet, const CKey& key)
  {
      LOCK(wallet.cs_wallet);
      wallet.AddKeyPubKey(key, key.GetPubKey());
  }
  
  BOOST_FIXTURE_TEST_CASE(rescan, TestChain100Setup)
  {
      LOCK(cs_main);
  
      // Cap last block file size, and mine new block in a new block file.
      CBlockIndex* const nullBlock = nullptr;
      CBlockIndex* oldTip = chainActive.Tip();
      GetBlockFileInfo(oldTip->GetBlockPos().nFile)->nSize = MAX_BLOCKFILE_SIZE;
      CreateAndProcessBlock({}, GetScriptForRawPubKey(coinbaseKey.GetPubKey()));
      CBlockIndex* newTip = chainActive.Tip();
  
      // Verify ScanForWalletTransactions picks up transactions in both the old
      // and new block files.
      {
          CWallet wallet;
          AddKey(wallet, coinbaseKey);
          BOOST_CHECK_EQUAL(nullBlock, wallet.ScanForWalletTransactions(oldTip));
          BOOST_CHECK_EQUAL(wallet.GetImmatureBalance(), 100 * COIN);
      }
  
      // Prune the older block file.
      PruneOneBlockFile(oldTip->GetBlockPos().nFile);
      UnlinkPrunedFiles({oldTip->GetBlockPos().nFile});
  
      // Verify ScanForWalletTransactions only picks transactions in the new block
      // file.
      {
          CWallet wallet;
          AddKey(wallet, coinbaseKey);
          BOOST_CHECK_EQUAL(oldTip, wallet.ScanForWalletTransactions(oldTip));
          BOOST_CHECK_EQUAL(wallet.GetImmatureBalance(), 50 * COIN);
      }
  
      // Verify importmulti RPC returns failure for a key whose creation time is
      // before the missing block, and success for a key whose creation time is
      // after.
      {
          CWallet wallet;
          vpwallets.insert(vpwallets.begin(), &wallet);
          UniValue keys;
          keys.setArray();
          UniValue key;
          key.setObject();
          key.pushKV("scriptPubKey", HexStr(GetScriptForRawPubKey(coinbaseKey.GetPubKey())));
          key.pushKV("timestamp", 0);
          key.pushKV("internal", UniValue(true));
          keys.push_back(key);
          key.clear();
          key.setObject();
          CKey futureKey;
          futureKey.MakeNewKey(true);
          key.pushKV("scriptPubKey", HexStr(GetScriptForRawPubKey(futureKey.GetPubKey())));
          key.pushKV("timestamp", newTip->GetBlockTimeMax() + TIMESTAMP_WINDOW + 1);
          key.pushKV("internal", UniValue(true));
          keys.push_back(key);
          JSONRPCRequest request;
          request.params.setArray();
          request.params.push_back(keys);
  
          UniValue response = importmulti(request);
          BOOST_CHECK_EQUAL(response.write(),
              strprintf("[{\"success\":false,\"error\":{\"code\":-1,\"message\":\"Rescan failed for key with creation "
                        "timestamp %d. There was an error reading a block from time %d, which is after or within %d "
                        "seconds of key creation, and could contain transactions pertaining to the key. As a result, "
                        "transactions and coins using this key may not appear in the wallet. This error could be caused "
                        "by pruning or data corruption (see sojucoind log for details) and could be dealt with by "
                        "downloading and rescanning the relevant blocks (see -reindex and -rescan "
                        "options).\"}},{\"success\":true}]",
                                0, oldTip->GetBlockTimeMax(), TIMESTAMP_WINDOW));
          vpwallets.erase(vpwallets.begin());
      }
  }
  
  // Verify importwallet RPC starts rescan at earliest block with timestamp
  // greater or equal than key birthday. Previously there was a bug where
  // importwallet RPC would start the scan at the latest block with timestamp less
  // than or equal to key birthday.
  BOOST_FIXTURE_TEST_CASE(importwallet_rescan, TestChain100Setup)
  {
      LOCK(cs_main);
  
      // Create two blocks with same timestamp to verify that importwallet rescan
      // will pick up both blocks, not just the first.
      const int64_t BLOCK_TIME = chainActive.Tip()->GetBlockTimeMax() + 5;
      SetMockTime(BLOCK_TIME);
      coinbaseTxns.emplace_back(*CreateAndProcessBlock({}, GetScriptForRawPubKey(coinbaseKey.GetPubKey())).vtx[0]);
      coinbaseTxns.emplace_back(*CreateAndProcessBlock({}, GetScriptForRawPubKey(coinbaseKey.GetPubKey())).vtx[0]);
  
      // Set key birthday to block time increased by the timestamp window, so
      // rescan will start at the block time.
      const int64_t KEY_TIME = BLOCK_TIME + TIMESTAMP_WINDOW;
      SetMockTime(KEY_TIME);
      coinbaseTxns.emplace_back(*CreateAndProcessBlock({}, GetScriptForRawPubKey(coinbaseKey.GetPubKey())).vtx[0]);
  
      // Import key into wallet and call dumpwallet to create backup file.
      {
          CWallet wallet;
          LOCK(wallet.cs_wallet);
          wallet.mapKeyMetadata[coinbaseKey.GetPubKey().GetID()].nCreateTime = KEY_TIME;
          wallet.AddKeyPubKey(coinbaseKey, coinbaseKey.GetPubKey());
  
          JSONRPCRequest request;
          request.params.setArray();
          request.params.push_back((pathTemp / "wallet.backup").string());
          vpwallets.insert(vpwallets.begin(), &wallet);
          ::dumpwallet(request);
      }
  
      // Call importwallet RPC and verify all blocks with timestamps >= BLOCK_TIME
      // were scanned, and no prior blocks were scanned.
      {
          CWallet wallet;
  
          JSONRPCRequest request;
          request.params.setArray();
          request.params.push_back((pathTemp / "wallet.backup").string());
          vpwallets[0] = &wallet;
          ::importwallet(request);
  
          BOOST_CHECK_EQUAL(wallet.mapWallet.size(), 3);
          BOOST_CHECK_EQUAL(coinbaseTxns.size(), 103);
          for (size_t i = 0; i < coinbaseTxns.size(); ++i) {
              bool found = wallet.GetWalletTx(coinbaseTxns[i].GetHash());
              bool expected = i >= 100;
              BOOST_CHECK_EQUAL(found, expected);
          }
      }
  
      SetMockTime(0);
      vpwallets.erase(vpwallets.begin());
  }
  
  // Check that GetImmatureCredit() returns a newly calculated value instead of
  // the cached value after a MarkDirty() call.
  //
  // This is a regression test written to verify a bugfix for the immature credit
  // function. Similar tests probably should be written for the other credit and
  // debit functions.
  BOOST_FIXTURE_TEST_CASE(coin_mark_dirty_immature_credit, TestChain100Setup)
  {
      CWallet wallet;
      CWalletTx wtx(&wallet, MakeTransactionRef(coinbaseTxns.back()));
      LOCK2(cs_main, wallet.cs_wallet);
      wtx.hashBlock = chainActive.Tip()->GetBlockHash();
      wtx.nIndex = 0;
  
      // Call GetImmatureCredit() once before adding the key to the wallet to
      // cache the current immature credit amount, which is 0.
      BOOST_CHECK_EQUAL(wtx.GetImmatureCredit(), 0);
  
      // Invalidate the cached value, add the key, and make sure a new immature
      // credit amount is calculated.
      wtx.MarkDirty();
      wallet.AddKeyPubKey(coinbaseKey, coinbaseKey.GetPubKey());
      BOOST_CHECK_EQUAL(wtx.GetImmatureCredit(), 50*COIN);
  }
  
  static int64_t AddTx(CWallet& wallet, uint32_t lockTime, int64_t mockTime, int64_t blockTime)
  {
      CMutableTransaction tx;
      tx.nLockTime = lockTime;
      SetMockTime(mockTime);
      CBlockIndex* block = nullptr;
      if (blockTime > 0) {
          auto inserted = mapBlockIndex.emplace(GetRandHash(), new CBlockIndex);
          assert(inserted.second);
          const uint256& hash = inserted.first->first;
          block = inserted.first->second;
          block->nTime = blockTime;
          block->phashBlock = &hash;
      }
  
      CWalletTx wtx(&wallet, MakeTransactionRef(tx));
      if (block) {
          wtx.SetMerkleBranch(block, 0);
      }
      wallet.AddToWallet(wtx);
      return wallet.mapWallet.at(wtx.GetHash()).nTimeSmart;
  }
  
  // Simple test to verify assignment of CWalletTx::nSmartTime value. Could be
  // expanded to cover more corner cases of smart time logic.
  BOOST_AUTO_TEST_CASE(ComputeTimeSmart)
  {
      CWallet wallet;
  
      // New transaction should use clock time if lower than block time.
      BOOST_CHECK_EQUAL(AddTx(wallet, 1, 100, 120), 100);
  
      // Test that updating existing transaction does not change smart time.
      BOOST_CHECK_EQUAL(AddTx(wallet, 1, 200, 220), 100);
  
      // New transaction should use clock time if there's no block time.
      BOOST_CHECK_EQUAL(AddTx(wallet, 2, 300, 0), 300);
  
      // New transaction should use block time if lower than clock time.
      BOOST_CHECK_EQUAL(AddTx(wallet, 3, 420, 400), 400);
  
      // New transaction should use latest entry time if higher than
      // min(block time, clock time).
      BOOST_CHECK_EQUAL(AddTx(wallet, 4, 500, 390), 400);
  
      // If there are future entries, new transaction should use time of the
      // newest entry that is no more than 300 seconds ahead of the clock time.
      BOOST_CHECK_EQUAL(AddTx(wallet, 5, 50, 600), 300);
  
      // Reset mock time for other tests.
      SetMockTime(0);
  }
  
  BOOST_AUTO_TEST_CASE(LoadReceiveRequests)
  {
      CTxDestination dest = CKeyID();
      pwalletMain->AddDestData(dest, "misc", "val_misc");
      pwalletMain->AddDestData(dest, "rr0", "val_rr0");
      pwalletMain->AddDestData(dest, "rr1", "val_rr1");
  
      auto values = pwalletMain->GetDestValues("rr");
      BOOST_CHECK_EQUAL(values.size(), 2);
      BOOST_CHECK_EQUAL(values[0], "val_rr0");
      BOOST_CHECK_EQUAL(values[1], "val_rr1");
  }
  
  class ListCoinsTestingSetup : public TestChain100Setup
  {
  public:
      ListCoinsTestingSetup()
      {
          CreateAndProcessBlock({}, GetScriptForRawPubKey(coinbaseKey.GetPubKey()));
          ::bitdb.MakeMock();
          wallet.reset(new CWallet(std::unique_ptr<CWalletDBWrapper>(new CWalletDBWrapper(&bitdb, "wallet_test.dat"))));
          bool firstRun;
          wallet->LoadWallet(firstRun);
          AddKey(*wallet, coinbaseKey);
          wallet->ScanForWalletTransactions(chainActive.Genesis());
      }
  
      ~ListCoinsTestingSetup()
      {
          wallet.reset();
          ::bitdb.Flush(true);
          ::bitdb.Reset();
      }
  
      CWalletTx& AddTx(CRecipient recipient)
      {
          CWalletTx wtx;
          CReserveKey reservekey(wallet.get());
          CAmount fee;
          int changePos = -1;
          std::string error;
          CCoinControl dummy;
          BOOST_CHECK(wallet->CreateTransaction({recipient}, wtx, reservekey, fee, changePos, error, dummy));
          CValidationState state;
          BOOST_CHECK(wallet->CommitTransaction(wtx, reservekey, nullptr, state));
          auto it = wallet->mapWallet.find(wtx.GetHash());
          BOOST_CHECK(it != wallet->mapWallet.end());
          CreateAndProcessBlock({CMutableTransaction(*it->second.tx)}, GetScriptForRawPubKey(coinbaseKey.GetPubKey()));
          it->second.SetMerkleBranch(chainActive.Tip(), 1);
          return it->second;
      }
  
      std::unique_ptr<CWallet> wallet;
  };
  
  BOOST_FIXTURE_TEST_CASE(ListCoins, ListCoinsTestingSetup)
  {
      std::string coinbaseAddress = coinbaseKey.GetPubKey().GetID().ToString();
      LOCK2(cs_main, wallet->cs_wallet);
  
      // Confirm ListCoins initially returns 1 coin grouped under coinbaseKey
      // address.
      auto list = wallet->ListCoins();
      BOOST_CHECK_EQUAL(list.size(), 1);
      BOOST_CHECK_EQUAL(boost::get<CKeyID>(list.begin()->first).ToString(), coinbaseAddress);
      BOOST_CHECK_EQUAL(list.begin()->second.size(), 1);
  
      // Check initial balance from one mature coinbase transaction.
      BOOST_CHECK_EQUAL(50 * COIN, wallet->GetAvailableBalance());
  
      // Add a transaction creating a change address, and confirm ListCoins still
      // returns the coin associated with the change address underneath the
      // coinbaseKey pubkey, even though the change address has a different
      // pubkey.
      AddTx(CRecipient{GetScriptForRawPubKey({}), 1 * COIN, false /* subtract fee */});
      list = wallet->ListCoins();
      BOOST_CHECK_EQUAL(list.size(), 1);
      BOOST_CHECK_EQUAL(boost::get<CKeyID>(list.begin()->first).ToString(), coinbaseAddress);
      BOOST_CHECK_EQUAL(list.begin()->second.size(), 2);
  
      // Lock both coins. Confirm number of available coins drops to 0.
      std::vector<COutput> available;
      wallet->AvailableCoins(available);
      BOOST_CHECK_EQUAL(available.size(), 2);
      for (const auto& group : list) {
          for (const auto& coin : group.second) {
              wallet->LockCoin(COutPoint(coin.tx->GetHash(), coin.i));
          }
      }
      wallet->AvailableCoins(available);
      BOOST_CHECK_EQUAL(available.size(), 0);
  
      // Confirm ListCoins still returns same result as before, despite coins
      // being locked.
      list = wallet->ListCoins();
      BOOST_CHECK_EQUAL(list.size(), 1);
      BOOST_CHECK_EQUAL(boost::get<CKeyID>(list.begin()->first).ToString(), coinbaseAddress);
      BOOST_CHECK_EQUAL(list.begin()->second.size(), 2);
  }
  
  BOOST_AUTO_TEST_SUITE_END()
  