[1.10.2] Why would you need to set a block state twice?

[American2050]

So I was looking at Minecraft code on the furnace and I found this:

 

if (active)
        {
            worldIn.setBlockState(pos, Blocks.LIT_FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
            worldIn.setBlockState(pos, Blocks.LIT_FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
        }
        else
        {
            worldIn.setBlockState(pos, Blocks.FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
            worldIn.setBlockState(pos, Blocks.FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
        }

 

What's the idea behind setting the block state 2 times there?

[Animefan8888]

So I was looking at Minecraft code on the furnace and I found this:

 

if (active)
        {
            worldIn.setBlockState(pos, Blocks.LIT_FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
            worldIn.setBlockState(pos, Blocks.LIT_FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
        }
        else
        {
            worldIn.setBlockState(pos, Blocks.FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
            worldIn.setBlockState(pos, Blocks.FURNACE.getDefaultState().withProperty(FACING, iblockstate.getValue(FACING)), 3);
        }

 

What's the idea behind setting the block state 2 times there?

I think it might be an error as back before blockstates they set the block once (if memory serves me well enough).

[Draco18s]

Yeah, it's just superfluous code.  It is technically a bug, but one that doesn't mean anything.

[jeffryfisher]

Fascinating... I wonder what the actual source code looks like. It might be something that looks complex on the surface but gets reduced and optimized so that our decompiled source looks like the above. That can happen when a complex situation in one version (the initial introduction of blockstates) gets simplified in a later version, but some patches of code retain bloat.