creep.moveTo doesn't return ERR_NO_PATH when all paths are blocked by creeps about engine HOT 2 OPEN

Are you sure you aren't using reusePath and the creep has a memorized path that hasn't expired yet?

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I have noticed similar issue. So far it seems that the problem comes from the fact that the path finding for this function returns unfinished path if the location is blocked.

If you are 10 tiles away from your location and only all tiles in range of 1 are blocked the path finder will provide you with path...but it will be one tile short. And your creep will move...1 tile short of its initial destination.

If you are however in range of 2 tiles and all tiles in range of 1 are blocked the path finder will not give you any path...resulting in ERR_NO_PATH being given.

However, this implementation works for sources and other structures on which you can't walk over without providing range:1 property to moveTo.

if(creep.harvest(source) === ERR_NOT_IN_RANGE){ creep.moveTo(source) }

This currently works...you will be given a path 1 tile away from the source...move to it..and stop receiving ERR_NOT_IN_RANGE.

However if this fix is to be implemented such code will return ERR_NO_PATH since there is no path that leads to the exact location (x,y).

In addition if you were to add default range:1 then when moving to flags or containers or any other walkable object...you will stop 1 tile short.

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