Poppy W can't block Yi Q? ???

Help? Halp? Is it a bug? Because I only chose poppy due to the fact there was a Yi/Leesin combo on enemy team so that I could protect the adc in late game teamfights While with Lee it works, Yi could just jump on her and murder her. It was disgusting. I'd have w up, laugh spam as lee sin is blocked, Then here comes Yi. Hue hue hue.

Shouldn't Poppy W beable to block all dashes? I mean I'd understand fizz E. But Master Yi's Q should be a dash. q.q