Merge pull request zcash#6918 from nuttycom/improve_gettransaction_constness

Add const modifer to the `blockIndex` argument to `GetTransaction`

Author: daira

src/main.cpp

@@ -2062,9 +2062,9 @@ bool GetAddressUnspent(const uint160& addressHash, int type,
  * Return transaction in txOut, and if it was found inside a block, its hash is placed in hashBlock.
  * If blockIndex is provided, the transaction is fetched from the corresponding block.
  */
-bool GetTransaction(const uint256& hash, CTransaction& txOut, const Consensus::Params& consensusParams, uint256& hashBlock, bool fAllowSlow, CBlockIndex* blockIndex)
+bool GetTransaction(const uint256& hash, CTransaction& txOut, const Consensus::Params& consensusParams, uint256& hashBlock, bool fAllowSlow, const CBlockIndex* blockIndex)
 {
-    CBlockIndex* pindexSlow = blockIndex;
+    const CBlockIndex* pindexSlow = blockIndex;
 
     LOCK(cs_main);
 

src/main.h

@@ -307,7 +307,7 @@ bool TestSetIBD(bool);
 /** Format a string that describes several potential problems detected by the core */
 std::pair<std::string, int64_t> GetWarnings(const std::string& strFor);
 /** Retrieve a transaction (from memory pool, or from disk, if possible) */
-bool GetTransaction(const uint256& hash, CTransaction& tx, const Consensus::Params& params, uint256& hashBlock, bool fAllowSlow = false, CBlockIndex* blockIndex = nullptr);
+bool GetTransaction(const uint256& hash, CTransaction& tx, const Consensus::Params& params, uint256& hashBlock, bool fAllowSlow = false, const CBlockIndex* blockIndex = nullptr);
 /** Find the best known block, and make it the tip of the block chain */
 bool ActivateBestChain(CValidationState& state, const CChainParams& chainparams, const CBlock* pblock = NULL);
 CAmount GetBlockSubsidy(int nHeight, const Consensus::Params& consensusParams);