New Twiddle

components.show-alert.js

import Ember from 'ember';
import injectFn from '../utils/inject-fn';

export default Ember.Component.extend({
  tagName: 'button',
  windowAlert: injectFn(),
  
  click() {
    const windowAlert = this.get('windowAlert');
    windowAlert('andrew');
  }
});

controllers.application.js

import Ember from 'ember';

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

initializers.register-fns.js

import windowAlert from '../utils/window-alert';
import dasherize from '../utils/dasherize';

const fns = { windowAlert };

export function initialize(app) {
  Object.keys(fns).forEach((fnName) => {
    app.register(
      `fn:${dasherize(fnName)}`,
      fns[fnName],
      { instantiate: false }
    );
  });
}

export default {
  initialize,
  name: 'register-fns'
};

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{#show-alert}}Show alert{{/show-alert}}
<br>
<br>

twiddle.json

{
  "version": "0.13.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.16.2",
    "ember-template-compiler": "2.16.2",
    "ember-testing": "2.16.2"
  },
  "addons": {
    "ember-data": "2.16.3"
  }
}

utils.dasherize.js

export default function dasherize(s) {
  return s.replace(/[A-Z]/, (c, i) => {
    const lc = c.toLowerCase();
    return (i === 0) ? lc : `-${lc}`;
  });
}

utils.inject-fn.js

import Ember from 'ember';
import dasherize from './dasherize';

export default function injectFn(fnName) {
  return Ember.computed(function(propertyName) {
    return Ember.getOwner(this).lookup(`fn:${dasherize(fnName || propertyName)}`);
  });
};

utils.window-alert.js

export default function windowAlert() {
  return window.alert(...arguments);
}