I doubt you're going to see one here... I see no way the prosecution is going to prove intent, and I betcha this gets thrown out with "no prospect of conviction" (isn't that how they phrase it?) before it gets to court.I'd just like to see some case law regarding water guns.
There was a case in Vancouver when someone was convicted of a assault with a weapon... a dildo
... and as I said, I've argued a case much like this one... the weapon was a letter and I was found not guilty, as the crown didn't prove intent to harm.