Autocomplete for Add New Site → Admin Email

[helen]

We have autocomplete for adding users to sites - we should do the same for the admin email for a new site.

Previously: #19810

[jeremyfelt]

This makes sense. I always end up relying on browser input history and that's no fun.

We would need to figure out what that list should look like and then how to retrieve that data in advance. Emails of users that are registered on the current network?

[helen]

I imagine we could make it use the same Ajax search that adding users to a site uses, just need to be able to have user_email as the value instead of user_login.

[helen]

Gave it a run in 25348.2.diff​. Had to switch to an explicit .each() in the JS (as opposed to relying on jQuery's implicit one) to have access to the element.

[jeremyfelt]

25348.2.diff​ looks good and tests good. +1

As expected, it restricts the user search to members of the current "site". When in the network admin, the current site is the current network, so the search returns properly. If I was to create a new network, users from other networks would not return in the search.

It may be interesting to have a filter in there one day to allow for the members of multiple networks to be searched at once. I don't think that's today though. :)

It could also be nice to have an index on user_email in the DB, but it looks like we've been down that road in a couple tickets and the answer is an alter table when needed.

[helen]

In 27046:

Autocomplete for the new site admin email. Better than trying to remember which email address you used.

fixes #25348.

[helen]

#15942 was marked as a duplicate.