When standing on farmland, wet or dry, with a water source next to the farmland, the player is given a small amount of movement in the opposite direction, about one block's worth. I discovered this in a survival world when I was standing on farmland next to a lake. I tested it in a superflat, creative world with one farmland block and one water source with the same results.

What I expected to happen was...:
I would stand on the farmland like normal, no unexpected movement.

What actually happened was...:
My player was pushed into the water and when I tried to jump back on land, I was pushed right back in.

Steps to Reproduce:
1. Place a farmland block, it does not need to be saturated.
2. Place a water source next to the farmland.
3. Step on the farmland.