PHP Notice: Only variables should be passed by reference

[joyously]

Trying ClassicPress 1.0.1 conversion from WP 5.2.2, my debug_log file has

PHP Notice: Only variables should be passed by reference in /wp-admin/includes/dashboard.php on line 1463

That line of code is
$active = array_shift( array_keys( $feeds ) );
The dashboard is showing two widgets with feeds (petitions and blog).

Possible solution

This could be because of using the same database as WordPress was using? It went through a page that updated the database, though.

Steps to reproduce

1. I extracted the CP zip to a folder
2. I copied the wp-config.php and the uploads folder from my wordpress folder to CP folder
3. I renamed the wordpress folder to x, and the CP folder to wordpress
4. I logged in to the site

[pattonwebz]

I will take care of this one today. I have encountered this problem before and I know the solution.

The output of array_keys() is not intuitive. It returns an array but it does not output one. It's a bit nuanced.

[pattonwebz]

I have created a PR to correct this notice. It introduces no breaking changes and is functionally exactly the same - it just rearranges things to satisfy strict php notice about this.

[nylen]

Thanks @pattonwebz!

I was able to confirm that this PR (#429) fixes the issue. Also quoting from my comment there:

This is a good example of why it's a good idea to add an automated test for any new code. This would have caught this error by executing the code in question against all of our supported PHP versions automatically, and failing if any notices or any other errors occur.