Gerund
Occasionally, a verb can function as a noun if “ing” is added to the end of it. As you may know, a noun can perform or receive an action, and when an “ing” is added to the end of a verb, this is possible. For instance, “write” is a verb is in “I write” where “I” is the subject, and “write” is the verb. However, if you add “ing” to “write” as in “writing,” it becomes a noun as it can therefore perform or receive the action as in “Writing makes me happy” or “I like writing.” That said, "wishing" is gerund and is serving as the subject of the sentence.