While farming I tilled dirt directly next to a waterblock, I expected to be able to walk on the new farmland unimpeded. Instead, I was essentially sucked into the waterblock.

After some testing, I've discovered that: It was not just water, its any 'empty space' next to the farmland. If you can fall off, the bug works. That it has to be next to the block, farmland diagonal to the empty space worked as intended. That this bug worked with path blocks, and soul sand but not slabs. That it does not work on dropped items. 

Steps to reproduce:

1. Find a space you could fall from: A hole, a ledge, the air, ontop of the ground, a river, etc.
2. Place a non-full block like farmland, directly next to the space: Soulsand, pathblock, farmland, etc. 
3. Stand, run, or walk on it. 
4. Get pushed off into the open space.