nested wildcard

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  actions: {
    transitionToThis() {
      // This applies to the *wildcard segment in the router, instead of :top-level
      // this.transitionToRoute('top-level.nested-wildcard', 'top-level-segment');
      this.transitionToRoute('top-level.nested-wildcard', 'top-level-segment', 'wildcard'); 
    }
  }
});

router.js

import Ember from 'ember';
import config from './config/environment';

const Router = Ember.Router.extend({
  location: 'none',
  rootURL: config.rootURL
});

Router.map(function() {
  this.route('top-level', { path: '/:top_model' }, function() {
    this.route('nested-wildcard', { path: '/something/*wildcard' });
  });
});

export default Router;

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<button {{action 'transitionToThis'}}>click me</button>
<br>
<br>

twiddle.json

{
  "version": "0.10.6",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.9.0",
    "ember-data": "2.9.0",
    "ember-template-compiler": "2.9.0",
    "ember-testing": "2.9.0"
  },
  "addons": {}
}