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 "bench.h"
  #include "wallet/wallet.h"
  
  #include <boost/foreach.hpp>
  #include <set>
  
  static void addCoin(const CAmount& nValue, const CWallet& wallet, std::vector<COutput>& vCoins)
  {
      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;
      CWalletTx* wtx = new CWalletTx(&wallet, MakeTransactionRef(std::move(tx)));
  
      int nAge = 6 * 24;
      COutput output(wtx, nInput, nAge, true /* spendable */, true /* solvable */, true /* safe */);
      vCoins.push_back(output);
  }
  
  // Simple benchmark for wallet coin selection. Note that it maybe be necessary
  // to build up more complicated scenarios in order to get meaningful
  // measurements of performance. From laanwj, "Wallet coin selection is probably
  // the hardest, as you need a wider selection of scenarios, just testing the
  // same one over and over isn't too useful. Generating random isn't useful
  // either for measurements."
  // (https://github.com/scicoin/scicoin/issues/7883#issuecomment-224807484)
  static void CoinSelection(benchmark::State& state)
  {
      const CWallet wallet;
      std::vector<COutput> vCoins;
      LOCK(wallet.cs_wallet);
  
      while (state.KeepRunning()) {
          // Empty wallet.
          for (COutput output : vCoins)
              delete output.tx;
          vCoins.clear();
  
          // Add coins.
          for (int i = 0; i < 1000; i++)
              addCoin(1000 * COIN, wallet, vCoins);
          addCoin(3 * COIN, wallet, vCoins);
  
          std::set<CInputCoin> setCoinsRet;
          CAmount nValueRet;
          bool success = wallet.SelectCoinsMinConf(1003 * COIN, 1, 6, 0, vCoins, setCoinsRet, nValueRet);
          assert(success);
          assert(nValueRet == 1003 * COIN);
          assert(setCoinsRet.size() == 2);
      }
  }
  
  BENCHMARK(CoinSelection);
  