block send logic seemingly ran twice for applyPhysics=false?

[BenchmarkMode]

Expected behavior

Cratblock.setBlockState()

 if (applyPhysics) {
            return world.setBlock(pos, newState, net.minecraft.world.level.block.Block.UPDATE_ALL);
        } else {
            boolean success = world.setBlock(pos, newState,
                net.minecraft.world.level.block.Block.UPDATE_CLIENTS |
                    net.minecraft.world.level.block.Block.UPDATE_KNOWN_SHAPE |
                    net.minecraft.world.level.block.Block.UPDATE_SKIP_ON_PLACE);
            if (success && world instanceof net.minecraft.world.level.Level) {
                world.getMinecraftWorld().sendBlockUpdated(
                    pos,
                    oldState,
                    newState,
                    net.minecraft.world.level.block.Block.UPDATE_ALL
                );
            }
            return success;
        }
    }

in setBlock it eventually checks for flag UPDATE_CLIENTS then runs sendBlockUpdated, so why do we run it again right after?

 if ((flags & UPDATE_CLIENTS) != 0 && (!this.isClientSide || (flags & UPDATE_INVISIBLE) == 0) && (this.isClientSide || chunkAt == null || (chunkAt.getFullStatus() != null && chunkAt.getFullStatus().isOrAfter(FullChunkStatus.FULL)))) { // allow chunk to be null here as chunk.isReady() is false when we send our notification during block placement // Paper - rewrite chunk system - change from ticking to full
                this.sendBlockUpdated(pos, blockState, state, flags);
            }

 if (success && world instanceof net.minecraft.world.level.Level) {
                world.getMinecraftWorld().sendBlockUpdated(
                    pos,
                    oldState,
                    newState,
                    net.minecraft.world.level.block.Block.UPDATE_ALL
                );
            }

this only happens when applyPhysics=false

Paper version

782ce95

Other

No response

[electronicboy]

I mean, the set block stuff is generally a mess due to the whole fact that it's around evolving code and there are many oddball CB hacks which might not cause it to always immediatly apply; I'd guess as with everything, the question boils down to "what happens if it's removed", does it break in certain cases, etc

[BenchmarkMode]

the flags passed into sendBlockUpdated are completely unused, I can say pretty confidently that sendBlockUpdated is called twice with the exact same parameters (excluding flags)

// oldstate comes from this.getChunkAt(pos).setBlockState(pos, state, flags) (setblockstate returns replaced block state)

BlockState state = newState;
BlockState blockState = oldState;

 if ((flags & 2) != 0 && (!this.isClientSide || (flags & 4) == 0) && (this.isClientSide || chunkAt == null || (chunkAt.getFullStatus() != null && chunkAt.getFullStatus().isOrAfter(FullChunkStatus.FULL)))) { // allow chunk to be null here as chunk.isReady() is false when we send our notification during block placement // Paper - rewrite chunk system - change from ticking to full
                this.sendBlockUpdated(pos, blockState, state, flags); // pos, oldState, newState
            }

// oldstate comes from this.getNMS(), which calls this.world.getBlockState(this.position)
// new state identical to that which is passed into world.setBlock
if (success && world instanceof net.minecraft.world.level.Level) {
                world.getMinecraftWorld().sendBlockUpdated(
                    pos,
                    oldState,
                    newState,
                    net.minecraft.world.level.block.Block.UPDATE_ALL
                ); // pos, oldState, newState
            }

if setBlockState returns what was there then it will be identical to this.world.getBlockState(this.position).

setBlockState can only return exactly what was there or null, if it was null setblock bails out anyways

[electronicboy]

There exists various states inside of setBlock which will not cause that logic to be called, it should be called later, however, is my understanding. I am pondering if there exists some cases that that duplicate logic fixes, esepcially in regards to that gating or plugins doing stuff.