Views EntityReference filter: Add functionality to switch from select to autocomplete widget when a max number of options reached

I have added MR 9866 to add this feature. Code was inspired by functionality that existed in https://www.drupal.org/files/issues/2020-09-30/2429699-351--on-9_1_x.patch → on 📌 Add Views EntityReference filter to be available for all entity reference fields Closed: duplicate .

Another reminder that you MUST follow the instruction on ✨ Continuation Add Views EntityReference filter to be available for all entity reference fields Needs work under the "How to use" heading to set up the EntityReference filter first for this to work.

Thanks for adding test coverage. For the new schema change will need an upgrade path for existing and test coverage for that update.

Hey! I'm writing this comment after reading that one of the remaining tasks is to get feedback from the community. I find this feature quite useful. In fact, in one of the projects I'm working on, there is a need to increase the maximum number of items in an exposed filter that contains many countries. I believe that the functionality provided here provides both increasing that limit in the views you want, as well as making future filters that exceed that limit in other views automatically have the autocomplete widget.

Example for unlimited items: 3481590-unlimited_items.png
Example with the limit set to 100 items: 3481590-limit-set-to-100-items.png