$this->datetimes_for_event should not be filled with array

[Arjen-Smit]

Problem this Pull Request solves

When filtering registrations on an event an error is thrown cause the $datetimes_for_event is filled with an array instead of a DatetimesForEventCheckIn.

How has this been tested

Steps to reproduce error:

• Go to Admin -> Event Espresso -> Registrations.
• Select Event Check-in
• Select an Event in the Filters and press Filter.

Checklist

• I have read the documentation relating to systems affected by this pull request, see https://github.com/eventespresso/event-espresso-core/tree/master/docs
• User input is adequately validated and sanitized
• all publicly displayed strings are internationalized (usually using esc_html__(), see https://codex.wordpress.org/I18n_for_WordPress_Developers)
• My code is tested.
• My code follows the Event Espresso code style.
• My code has proper inline documentation.
• My code accounts for when the site is in Maintenance Mode (MM2 especially disallows usage of models)

[tn3rb]

thanks @Arjen-Smit

this has already been fixed in the upcoming verion of EE

[Arjen-Smit]

Hi @tn3rb
This got me a bit confused, I would think dev is the upcoming version of EE?

Is there any indication when this will be available ?
We are currently using the dev version because we needed the recurring events feature for our platform.

[tn3rb]

This got me a bit confused, I would think dev is the upcoming version of EE?

HA! Yes that would make sense wouldn't it?

Because of the difficulties developing new features and/or refactoring code when changes span across multiple plugins, we decided to merge all of our 50-60 active repos into a single monorepo. So now all PHP development for all of our active plugins happens on a single private repo.

I'm currently wrestling with getting all of the CI/CD stuff configured for automagically deploying code to our various servers, services, and public repos like this one, but that's a crazy jigsaw puzzle to work with.
Since that's not ready yet, I can try to get dev branch here updated manually within the next week.