What is the test for an interim injunction?

This application for an interim injunction is governed by the three part test set out in R.J.R. MacDonald v. Canada 1994 CanLII 117 (SCC), [1994] 1 S.C.R. 311 at para. 48: First, a preliminary assessment must be made of the merits of the case to ensure that there is a serious question to be tried. Secondly, it must be determined whether the applicant would suffer irreparable harm if the application were refused. Finally, an assessment must be made as to which of the parties would suffer greater harm from the granting or refusal of the remedy pending a decision on the merits. Is there a serious question to be tried?