stephenharris/possible-bug-with-remove-action.php

## possible-bug-with-remove-action.php
<?php

/**
 * Possible Bug With remove_action()/remove_filter()
 *
 * Only been tested with the pre_get_posts hook
 *
 * A hook is trigged. If a function removes itself from that that hook, all functions
 * added with priority 10 are not triggered on that specific instance.
 *
 * Below the first function removes itself - it then re-adds itself so that it removes itself
 * every time the hook is trigged. Consequently the second function is never called.
 *
 * Try removing 'add_action'. The second function fires, but it fires 'late'
 * (i.e. it misses the first instance of pre_get_posts because in that instance remove_myself()
 * removed itself).
 *
 * Try removing 'remove_action()'. Everything works as expected.
 *
 * Instead try changing the priority of the second function - works fine...
 * ...so long as its not between 8-10.
 *
 * Does this work for you? Is this a known bug?
*/

add_action( 'pre_get_posts', 'remove_myself', 8 );
function remove_myself( $query ) {

	remove_action( 'pre_get_posts', 'remove_myself', 8 );
	add_action( 'pre_get_posts', 'remove_myself', 8 );
	return $query;
}
add_action( 'pre_get_posts', 'never_fired', 10 );
function never_fired(){
	echo 'Number of times pre_get_posts has been triggered: ' . did_action( 'pre_get_posts' );
	wp_die("I'm never fired");
}