Strange issue with Attack/Attack range

[Andrene]

I have a unit who has an attack with a range of 150 and no defined projectile, so it just deals instantly.
If the target for the unit is out of range the unit runs to a random(seemingly) side of the target, and attacks it from point blank(melee),
If the target is in range it attacks it like normal(from a distance, not caring what side its facing)

If I double click a unit it also moves towards it while attacking, but from reading other issues it seems like thats "intended"(not really intended, more of a complex "bug"?), not really that important to figure out as the same effect could be achieved with proper micro...Although it causes animation to get weird.