WordPress mu-plugin for logging stacktraces in WordPress code

pvw_logging.php

<?php

// Add this file to the wp-content/mu-plugins/ directory.
// It may need to be created if it doesn't exist

/**
 * These constants must be set in wp-config.php
 *
 * define('WP_DEBUG', true);
 * define('WP_DEBUG_LOG', true);
 * define('WP_DEBUG_DISPLAY', false);
 *
 */

function pvw_generate_trace() {
	$e     = new Exception();
	$trace = explode( "\n", $e->getTraceAsString() );
	// reverse array to make steps line up chronologically
	$trace = array_reverse( $trace );
	array_shift( $trace ); // remove {main}
	array_pop( $trace ); // remove call to this method
	$length = count( $trace );
	$result = array();
	for ( $i = 0; $i < $length; $i ++ ) {
		$result[] = ( $i + 1 ) . ')' . substr( $trace[ $i ], strpos( $trace[ $i ], ' ' ) ); // replace '#someNum' with '$i)', set the right ordering
	}

	return "\t" . implode( "\n\t", $result );
}

function pvw_trace( $message ) {
	error_log( 'PVW Debug: ' . $message );
	error_log( print_r( pvw_generate_trace(), true ) );
}


// Eg. place this function call somewhere in your code to see what is calling it
// The $message parameter gives context to the log if you are using it in multiple places

// pvw_trace( 'inserting default registration form' );