Recycled Route State

components.conditional-state.js

import Ember from 'ember';

export default Ember.Component.extend({
  init() {
    this._super();
    this.instanceState = "I was created at: " + Date.now();
  }
});

components.never-same.js

import Ember from 'ember';

const { get, set } = Ember;

export default Ember.Component.extend({
  getContent() {
    const obj = get(this, 'model');
    if (!obj) { return obj; }
    if (typeof obj === 'object' && obj.content) {
      return get(obj, 'content');
    }
    
    return obj;
  },
  
  didUpdateAttrs() {
    let newContent = this.getContent();
    let isSlotOne = get(this, 'useSlotOne');
    
    if (isSlotOne && newContent !== get(this, 'slotOne')) {
      set(this, 'slotTwo', newContent);
      set(this, 'useSlotOne', false);
    } else if (!isSlotOne && newContent !== get(this, 'slotTwo')) {
      set(this, 'slotOne', newContent);
      set(this, 'useSlotOne', true);
    }
  },
  
  init() {
    this._super();
    this.useSlotOne = true;
    this.slotOne = this.getContent();
    this.slotTwo = null;
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle'
});

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('my-route', { path: '/:id' });
});

export default Router;

routes.my-route.js

import Ember from 'ember';

export default Ember.Route.extend({
  someRouteState: null,
  
  beforeModel() {
    const params = this.paramsFor(this.routeName);
    const id = params.id;
    
    if (!this.someRouteState || this.someRouteState.routeId !== id) {
      this.someRouteState = {
        routeId: id
      };
    }
  },

  model({ id }) {
    return {
      id,
      name: 'I am model ' + id
    };
  },

  setupController(controller, model) {
    this._super(controller, model);
    Ember.set(controller, 'state', this.someRouteState);
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
{{#link-to 'my-route' '1'}}Go to model 1{{/link-to}}
{{#link-to 'my-route' '2'}}Go to model 2{{/link-to}}
<br>
{{outlet}}
<br>
<br>

templates.components.conditional-state.hbs

<h3>Unbound model.name: {{unbound model.name}}</h3>
<h3>model.name: {{model.name}}</h3>
<h3>Instance (init()) state: {{instanceState}}</h3>

templates.components.never-same.hbs

{{#if useSlotOne}}
  {{yield slotOne}}
{{else}}
  {{yield slotTwo}}
{{/if}}

templates.my-route.hbs

<h1>I am route {{model.id}}</h1>
<h2>I am some route state: {{state.routeId}}</h2>
{{conditional-state model=model}}
<br><hr><br>
{{#never-same model=model as |model|}}
  {{conditional-state model=model}}
{{/never-same}}

twiddle.json

{
  "version": "0.12.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.12.0",
    "ember-template-compiler": "2.12.0",
    "ember-testing": "2.12.0"
  },
  "addons": {
    "ember-data": "2.12.1"
  }
}