[Vuejs]-What does `args.unshift(this)` do in Vue's use.js?

Since you are inside of a Vueinstance, the lines in question are in the function defined on Vue.use the this most likely will reference the current Vue instance.

You will have to browse the source of toArray to understand the first line, it might takes the arguments and returning an array from them, and maybe substracting the first argument (the 1 in toArray(arguments, 1) give me this impression but to be sure browse the source of that function).

But then when the call args.unshift(this)comes it puts the Vue instance as the first element of the args array which is then used to provide arguments to the plugin function.

Hope that helps 😉

Seb