What is the range of a Dart Trap?

I just had the best idea ever: A self-harvesting Glowing Mushroom farm using Dart Traps.

However, since they don't exactly grow on trees, I'd like to use a minimum amount of Dart Traps for a maximum of Mushroom-covered ground.

Does anyone know how far a Dart Trap can fire a poison dart? They just seem to go in a straight line, but is their range actually infinite, or does the dart drop to the ground or disappear at some point?

Solution 1:

According to the wiki, darts can go for 2700 blocks.

Solution 2:

As far as I can tell their range is infinite.

From tests on a large world I went through at least 3 biomes (after cutting some holes in the ground) before hitting a large mountain I did not want to tunnel through (so at least a thousand feet or so).