What is the Expected Behaviour of Date Validation?

It’s validation day!

So I have a date input that I have set a “Date” validation on… but if the field is left empty then the validation does not trigger. I seem to also need a “Required” validation rule to trigger an error on an empty field.

Is this the expected behaviour? Is an empty date field considered to be a valid date?

And then… when I specify a date in the app, it is still listed as being invalid! Am I missing something here, or is this a bug?

Here is the code:

<input id="i_create_activity_start_date" name="start_date" is="dmx-date-picker" format="dddd D MMMM YYYY" type="text" class="form-control input_text" autocomplete="banana" dmx-bind:value="" value="" data-rule-date="" data-msg-date="Please specify a valid start date for the activity" required="" data-msg-required="Please specify a start date for the activity">

This seems to be related to this post: