discourse/app/assets/javascripts/wizard/components/invite-list.js.es6

export default Ember.Component.extend({
  classNames: ["invite-list"],
  users: null,
  inviteEmail: "",
  inviteRole: "",
  invalid: false,

  init() {
    this._super();
    this.set("users", []);

    this.set("roles", [
      { id: "moderator", label: I18n.t("wizard.invites.roles.moderator") },
      { id: "regular", label: I18n.t("wizard.invites.roles.regular") }
    ]);

    this.updateField();
  },

  keyPress(e) {
    if (e.keyCode === 13) {
      e.preventDefault();
      e.stopPropagation();
      this.send("addUser");
    }
  },

  updateField() {
    const users = this.get("users");

    this.set("field.value", JSON.stringify(users));

    const staffCount = this.get("step.fieldsById.staff_count.value") || 1;
    const showWarning = staffCount < 3 && users.length === 0;

    this.set("field.warning", showWarning ? "invites.none_added" : null);
  },

  actions: {
    addUser() {
      const user = {
        email: this.get("inviteEmail") || "",
        role: this.get("inviteRole")
      };

      if (!/(.+)@(.+){2,}\.(.+){2,}/.test(user.email)) {
        return this.set("invalid", true);
      }

      const users = this.get("users");
      if (users.findBy("email", user.email)) {
        return this.set("invalid", true);
      }

      this.set("invalid", false);

      users.pushObject(user);
      this.updateField();

      this.set("inviteEmail", "");
      Ember.run.scheduleOnce("afterRender", () =>
        this.$(".invite-email").focus()
      );
    },

    removeUser(user) {
      this.get("users").removeObject(user);
      this.updateField();
    }
  }
});