public async Task GetExtraDataForFillingBlockHeaderAsync_Test()
        {
            //null situation
            var blockHeader = new BlockHeader
            {
                Height = 1
            };
            var result = await _blockExtraDataProvider.GetBlockHeaderExtraDataAsync(blockHeader);

            result.ShouldBeNull();

            //with data
            var chain = await _blockchainService.GetChainAsync();

            var height = chain.BestChainHeight;
            var hash   = chain.BestChainHash;

            var result1 = await _blockExtraDataProvider.GetBlockHeaderExtraDataAsync(new BlockHeader
            {
                PreviousBlockHash = hash,
                Height            = height
            });

            result1.ShouldNotBeNull();
        }
        public async Task FillExtraData_GenesisHeight_Test()
        {
            var header = new BlockHeader
            {
                PreviousBlockHash = HashHelper.ComputeFrom("PreviousHash"),
                Height            = 1
            };
            var bytes = await _crossChainBlockExtraDataProvider.GetBlockHeaderExtraDataAsync(header);

            Assert.Empty(bytes);
        }