muplugins_loaded hook is not triggered

Question

I am creating my very first Wordpress plugin. I intend to make this a wrapper, so it should be initialized before other elements are initialized and finalized after other elements are finalized.

I have been researching the actions here and thought muplugins_loaded and shutdown should be the right events for my scenario.

muplugins_loaded is supposed to be executed

After must-use plugins are loaded

so, I have a code like this:

defined( 'ABSPATH' ) or die( 'No script kiddies please!' );

//Checking whether queries are to be saved
if ( defined( 'SAVEQUERIES' ) && SAVEQUERIES ) {

    //definition of the WordpressBenchmarker class    

    function initWordpressBenchmark() {
        WordpressBenchmarker::initialize();
    }

    function finalizeWordpressBenchmark() {
        WordpressBenchmarker::finish();
    }

    add_action( 'muplugins_loaded', 'initWordpressBenchmark', 1 );
    add_action( 'shutdown', 'finalizeWordpressBenchmark', 20 );

}

I get this error:

Call to a member function finalize() on a non-object in

which clearly points to this line:

WordpressBenchmarker::finish();

which, believe me that surely means that initWordpressBenchmark was not executed. This makes me think that the plugin was not executed because it is not a must used plugin. Should I make it a must used plugin? Is there a better way? As an alternative I am thinking using the plugins_loaded hook with a value which is smaller than any other values. After searching for references for plugins_loaded I have seen that the smallest number for priorities was 0. I am wondering whether a negative value as the priority

add_action( 'plugins_loaded', 'initWordpressBenchmark', -1 );

would be a good solution.

Answer 1

muplugins_loaded is not triggered for not must used plugins. It would be an unorthodox approach to make my benchmarking plugin a must used plugin, since benchmarking is not a must used feature by definition, but rather a plugin which needs to be used when optimization is needed. So, I have decided to not make my plugin a must used plugin. Instead of that, I have modified my hook to be triggered upon plugins_loaded instead of muplugins_loaded. I have added the hook with a priority of -1 and have used a low priority for the shutdown hook. This apparently solved the issue:

add_action( 'plugins_loaded', 'initWordpressBenchmark', -1 );
add_action( 'shutdown', 'finalizeWordpressBenchmark', 1001 );