Here is my current solution which adds in a current date and does some calculations with the date from the content.
In the controller, add the current date to the data:
$this->view->assign('date_now', new \DateTime());
This is available as {date_now} in fluid then:
<f:if condition="{f:format.date(date: date_now, format: '(Y-m-d)')} > {f:format.date(date: '{event.date}-4 weeks', format: '(Y-m-d)')}">
<f:then>
<p>Event date is past</p>
</f:then>
<f:else>
<p>Event date is upcoming</p>
</f:else>
</f:if>
Note how on the right side, where some calculation is done, additional quotes and curly brackets come in ('{event.date}-4 weeks'
).
PS I prefer the Y-m-d
format to U
for a date comparison, as we don't want to compare the current time – just the date.