How many blocks away will farmer villagers without a village farm?

Assuming I place a water block away from any village, and I put a composter and a villager above the water block and plant crops all around it, what is the radius of crops that the farmer will tend to on Java edition 1.14.4?

Minecraft 1.16.3:

The farmer with inventory filled with carrots and potatoes got a composter in the middle of fully grown wheat field; random tick speed set to zero so that he wouldn't harvest the carrots and potatoes. Afterwards, the game has been tick-warped for 72 hours equivalent - in the latter half the villager would no longer replant anything. Afterwards, I added the diorite blocks to help measure the distance.

This is the pattern produced:

So, the harvested area is approximately a diamond with taxicab distance radius of 9.

According to the Minecraft wiki, a farmer villager will only seek farmland 9 blocks away in the X and Z coordinates, and up to 1 block away in the Z coordinates. Farmer villagers will only tend to crops inside their village boundary unless they are far enough from a village, in which they will cater to any crops.