mtt.register("util/normalize_players_and_add_recipients", function(callback)
local recipients = {}
local undeliverable = {}
local to = mail.normalize_players_and_add_recipients("sender", "player1,player2", recipients, undeliverable)
assert(to == "player1, player2")
assert(not next(undeliverable))
assert(recipients["player1"])
assert(recipients["player2"])
callback()
end)
