PaperMC/nms-patches/ItemWaterLily.patch

--- a/net/minecraft/server/ItemWaterLily.java
+++ b/net/minecraft/server/ItemWaterLily.java
@@ -30,7 +30,15 @@
                 Fluid fluid = world.getFluid(blockposition);
 
                 if ((fluid.c() == FluidTypes.c || material == Material.ICE) && world.isEmpty(blockposition1)) {
+                    // CraftBukkit start - special case for handling block placement with water lilies
+                    org.bukkit.block.BlockState blockstate = org.bukkit.craftbukkit.block.CraftBlockState.getBlockState(world, blockposition1);
                     world.setTypeAndData(blockposition1, Blocks.LILY_PAD.getBlockData(), 11);
+                    org.bukkit.event.block.BlockPlaceEvent placeEvent = org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPlaceEvent(world, entityhuman, enumhand, blockstate, blockposition.getX(), blockposition.getY(), blockposition.getZ());
+                    if (placeEvent != null && (placeEvent.isCancelled() || !placeEvent.canBuild())) {
+                        blockstate.update(true, false);
+                        return new InteractionResultWrapper(EnumInteractionResult.PASS, itemstack);
+                    }
+                    // CraftBukkit end
                     if (entityhuman instanceof EntityPlayer) {
                         CriterionTriggers.y.a((EntityPlayer) entityhuman, blockposition1, itemstack);
                     }