If a fluid, or a block that is destroyed when a piston tries to push into its space, is at the top or bottom of the world and a piston tries to push a solid block into its space towards the top or bottom of the world respectively, the piston is not activated and nothing happens.

How to reproduce:

1. Execute the following commands:

   /setblock ~ 319 ~ minecraft:water

   /setblock ~ 318 ~ minecraft:stone

   /setblock ~ 317 ~ minecraft:piston[facing=up]

2. Place a button under the piston.
3. Press the button.

Expected result:

Pistons would be able to successfully push a solid block from above or below to destroy a fluid or a block breakable by pistons at the top or bottom of the world.

Observed result:

Pistons cannot destroy fluids or blocks breakable by pistons at the top or bottom of the world by pushing a solid block into them from above or below.