BP_Group_Extension::_register() should only run if there is a valid group ID

[r-a-y]

In #4785 some work was done to overhaul the access and visibility control for group tabs.

However, if there is no group ID, BP_Group_Extension::_register() should not continue as it runs a few DB queries to check access and visibility.

To test, navigate to a user page and check the queries that are run.

[r-a-y]

01.patch bails out of the BP_Group_Extension::_register() method if there is no valid group ID. I'm hoping there aren't any unforeseen issues with doing this.

[boonebgorges]

I doubt there will be unforeseen issues, but it's possible - there may be plugins that analyze the available BP_Group_Extension extension on each pageload, and leaving them half-initialized could be a problem for them.

A more conservative approach is to bail at the beginning of user_meets_access_condition() if $this->group_id is empty. Will that take care of the db queries?

[r-a-y]

A more conservative approach is to bail at the beginning of user_meets_access_condition() if $this->group_id is empty. Will that take care of the db queries?

Yup, that works. However, there is a backward compatibility block before that, which does a groups_get_group() call. (It doesn't run for me at the moment, but just wanted to list that.)

Could the group ID check go at the very beginning of the setup_access_settings() method?

[boonebgorges]

Yup, let's go with that. Thanks, r-a-y!

[r-a-y]

In 8827:

Do not process BP_Group_Extension::setup_access_settings() if no group ID is available.

If no group ID is available, the BP_Group_Extension::setup_access_settings()
method should not do its checks. This is to avoid running DB queries
unnecessarily. (See #4785.)

Fixes #5812.