Reported here: https://github.com/bitcoin/bitcoin/pull/10244#issuecomment-378035305

Travis log here: https://travis-ci.org/bitcoin/bitcoin/jobs/361243719#L2810

Note the JSON exception:

```
test_framework.authproxy.JSONRPCException: The mempool was not loaded yet (-1) 
```

That exception was introduced here: https://github.com/bitcoin/bitcoin/commit/cb1e319fe9e198c9c5cf5236fe9af5a3d748b9e8#diff-a0c8f511d90e83aa9b5857e819ced344R1617

cc @jtimon 
}
    if (!pblockindex) {
        throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Block not found");
    }
    if (!fVerbose)
    {
        CDataStream ssBlock(SER_NETWORK, PROTOCOL_VERSION);
        ssBlock << pblockindex->GetBlockHeader();
        std::string strHex = HexStr(ssBlock.begin(), ssBlock.end());
        return strHex;
    }
    return blockheaderToJSON(tip, pblockindex);
}
static CBlock GetBlockChecked(const CBlockIndex* pblockindex)
{
    CBlock block;
    if (IsBlockPruned(pblockindex)) {
        throw JSONRPCError(RPC_MISC_ERROR, "Block not available (pruned data)");
    }
    if (!ReadBlockFromDisk(block, pblockindex, Params().GetConsensus())) {
        
        
        
        
        
        throw JSONRPCError(RPC_MISC_ERROR, "Block not found on disk");
    }
    return block;
}
static UniValue getblock(const JSONRPCRequest& request)