I came across this in a server today, and I tested it on a single player world.
World Size: 1×
Oceans: Ocean World
If you have all the setting on above, the world will spawn you on a small lonely island. The oceans seem to be fairly big and is probably a pain to swim to the other side.
I thought I’d post this Incase anyone else was interested.
There was a pine tree, but I cut it down before taking the picture.