text: // Copyright (c) 2011-2015 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/validation.h"
  #include "key.h"
  #include "validation.h"
  #include "miner.h"
  #include "pubkey.h"
  #include "txmempool.h"
  #include "random.h"
  #include "script/standard.h"
  #include "test/test_kash.h"
  #include "utiltime.h"
  
  #include <boost/test/unit_test.hpp>
  
  BOOST_AUTO_TEST_SUITE(tx_validationcache_tests)
  
  static bool
  ToMemPool(CMutableTransaction& tx)
  {
      LOCK(cs_main);
  
      CValidationState state;
      return AcceptToMemoryPool(mempool, state, MakeTransactionRef(tx), false, NULL, true, 0);
  }
  
  BOOST_FIXTURE_TEST_CASE(tx_mempool_block_doublespend, TestChain100Setup)
  {
      // Make sure skipping validation of transctions that were
      // validated going into the memory pool does not allow
      // double-spends in blocks to pass validation when they should not.
  
      CScript scriptPubKey = CScript() <<  ToByteVector(coinbaseKey.GetPubKey()) << OP_CHECKSIG;
  
      // Create a double-spend of mature coinbase txn:
      std::vector<CMutableTransaction> spends;
      spends.resize(2);
      for (int i = 0; i < 2; i++)
      {
          spends[i].nVersion = 1;
          spends[i].vin.resize(1);
          spends[i].vin[0].prevout.hash = coinbaseTxns[0].GetHash();
          spends[i].vin[0].prevout.n = 0;
          spends[i].vout.resize(1);
          spends[i].vout[0].nValue = 11*CENT;
          spends[i].vout[0].scriptPubKey = scriptPubKey;
  
          // Sign:
          std::vector<unsigned char> vchSig;
          uint256 hash = SignatureHash(scriptPubKey, spends[i], 0, SIGHASH_ALL);
          BOOST_CHECK(coinbaseKey.Sign(hash, vchSig));
          vchSig.push_back((unsigned char)SIGHASH_ALL);
          spends[i].vin[0].scriptSig << vchSig;
      }
  
      CBlock block;
  
      // Test 1: block with both of those transactions should be rejected.
      block = CreateAndProcessBlock(spends, scriptPubKey);
      BOOST_CHECK(chainActive.Tip()->GetBlockHash() != block.GetHash());
  
      // Test 2: ... and should be rejected if spend1 is in the memory pool
      BOOST_CHECK(ToMemPool(spends[0]));
      block = CreateAndProcessBlock(spends, scriptPubKey);
      BOOST_CHECK(chainActive.Tip()->GetBlockHash() != block.GetHash());
      mempool.clear();
  
      // Test 3: ... and should be rejected if spend2 is in the memory pool
      BOOST_CHECK(ToMemPool(spends[1]));
      block = CreateAndProcessBlock(spends, scriptPubKey);
      BOOST_CHECK(chainActive.Tip()->GetBlockHash() != block.GetHash());
      mempool.clear();
  
      // Final sanity test: first spend in mempool, second in block, that's OK:
      std::vector<CMutableTransaction> oneSpend;
      oneSpend.push_back(spends[0]);
      BOOST_CHECK(ToMemPool(spends[1]));
      block = CreateAndProcessBlock(oneSpend, scriptPubKey);
      BOOST_CHECK(chainActive.Tip()->GetBlockHash() == block.GetHash());
      // spends[1] should have been removed from the mempool when the
      // block with spends[0] is accepted:
      BOOST_CHECK_EQUAL(mempool.size(), 0);
  }
  
  BOOST_AUTO_TEST_SUITE_END()
  