[15531] breaks is_*() conditional tags

[freddyware]

#14494 suggested moving the is_*() conditional tags into the WP_Query class and [15531] changed trunk/wp-includes/query.php to redirect those calls to the global $wp_query object.

However, it appears that this move has broken at least one of the conditional tags because $wp_query isn't known -- this is the error:

Fatal error: Call to a member function is_feed() on a non-object in /home/frederickd/frederickding.com/wordpress/wp-includes/query.php on line 270

See line 270.​

Right now I am experiencing this critical error on the homepage of a site running trunk.

[freddyware]

is_feed() creates a critical error that stops execution.

[ryan]

Is the theme calling is_feed() before $wp_query is created?

[freddyware]

Aha. I did a debug_backtrace() and found that the violating line was in the W3 Total Cache plugin, which calls is_feed() on line 807 of w3-total-cache/lib/W3/Plugin/Minify.php.

While I recognize that this is now a bug in a plugin and not core, it seems problematic that this core commit breaks W3 Total Cache. I guess I now have to ... disable the caching plugin.

Is there any way that this move can be made more backward-compatible?

[scribu]

This change only makes the error in W3 Total Cache more apparent. Previously, it would have triggered a notice, which normally isn't displayed.

So this is actually a good oportunity for the plugin author to fix the code.

[nacin]

Going to manage the side effects of [15531] in #14729.