ntil any
previous async helper has completed and any subsequent async helper will wait
for it to finish before running.</p>
<p>The helper method will always be called with the current Application as the
first parameter. Other parameters, such as assert, need to be provided when calling the helper. Helpers need to be registered prior to calling
<code>startApp</code>, but ember-cli will take care of it for you.</p>
<p>Here is an example of a non-async helper:</p>
<div class="filename javascript"><div class="r