extends - Allows declaratively extending another component without having to use Vue.extend. This is primarily intended to make it easier to extend between single file components.
t { assert(VUEComponent.extends("a").extends == ["a"]); assert(VUEComponent.extends(["a","b"]).extends == ["a","b"]); assert(VUEComponent.extends("a").extends("x").extends == ["a", "x"]); // TODO: assert(VUEComponent.extends("a").extends("x").removeExtends("a").extends == ["x"]); assert(VUEComponent.extends(["a","b"]).clearExtends.extends == null)