List of Related bugs:
MC-214546
MC-125936
MC-147233
Skeletons shooting arrows can have their arrows bounced off a shield, through them, and into another mob. Initially discovered this bug while caving and used it to kill bats, but during testing found this can be used from everything from getting zombies to attack skeletons to creeper farming.
Testing also confirmed that this is abusable as long as you are between 1.1 and 4ish blocks away.
Linked issues
duplicates
Comments


Did you mean to comment this on MC-231409?

@theduke Did you mean to comment that on another issue?
I believe the core issue here is MC-147233.
After some further investigation I was able to figure out the cause.
A villager seems to randomly pick a free job site block in the area, even if it can't pathfind to the target.
So if a unreachable block is assigned, the villager will ignore another one, even if it is right in front of it.
Further, it seems like re-assignment happens after some time, so eventually the reachable one will be chosen and the villager takes the job.
Seems like the obvious fix is to exclude unreachable job blocks from the selection.