https://travis-ci.org/github/bitcoin/bitcoin/jobs/680452476#L6107
if (!tx || hashBlock.IsNull()) {
            throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Transaction not yet in block");
        }
        pblockindex = LookupBlockIndex(hashBlock);
        if (!pblockindex) {
            throw JSONRPCError(RPC_INTERNAL_ERROR, "Transaction index corrupt");
        }
    }
    CBlock block;
    if (!ReadBlockFromDisk(block, pblockindex, Params().GetConsensus())) {
        throw JSONRPCError(RPC_INTERNAL_ERROR, "Can't read block from disk");
    }
    unsigned int ntxFound = 0;
    for (const auto& tx : block.vtx) {
        if (setTxids.count(tx->GetHash())) {
            ntxFound++;
        }
    }
    if (ntxFound != setTxids.size()) {
        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Not all transactions found in specified or retrieved block");
    }
    CDataStream ssMB(SER_NETWORK, PROTOCOL_VERSION | SERIALIZE_TRANSACTION_NO_WITNESS);
    CMerkleBlock mb(block, setTxids);
    ssMB << mb;
    std::string strHex = HexStr(ssMB);
    return strHex;
},
    };
}
static RPCHelpMan verifytxoutproof()