escape-css-helper

controllers.application\.js

import Controller from '@ember/controller';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
	theColor = 'red';
}

helpers.escape-css\.js

import { helper } from '@ember/component/helper';
import { htmlSafe, isHTMLSafe } from '@ember/string';

function escapeCss([stringToEscape]) {
  let cssEscapedString = CSS.escape(stringToEscape);
  let htmlSafeString = htmlSafe(cssEscapedString);
  return htmlSafeString;
}

// from https://github.com/romulomachado/ember-cli-string-helpers/blob/master/addon/-private/create-string-helper.js

function wrapFunction(stringFunction) {
  return function([string]) {
    if (isHTMLSafe(string)) {
      string = string.string;
    }

    string = string || '';
    return stringFunction([string]);
  };
}

export default helper(wrapFunction(escapeCss));

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>
<div style="background-color: {{escape-css this.theColor}}; width: 20px; height: 20px;">
</div>

twiddle\.json

{
  "version": "0.17.0",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.17.0",
    "ember-template-compiler": "3.17.0",
    "ember-testing": "3.17.0"
  },
  "addons": {
    "@glimmer/component": "1.0.0"
  }
}