Check user capabilities

microtime-check-user-capabilities.php

<?php
add_action( 'init', function() {
	$check_list_of_caps = [ 'custom_capability_one', 'custom_capability_two', 'manage_options' ];

	// Test one
	$time_start = microtime( true );

  // Get current user caps
	$all_users_caps = wp_get_current_user()->allcaps;

  // Check against wanted ones
	$has_cap = array_intersect( $check_list_of_caps, array_keys( $all_users_caps ) );
  
  // Empty cap
  $has_cap = ?: false;

	// End test one
	$time_end = microtime( true );

	echo '<b>Total Execution Time test 1:</b> ' . ( $time_end - $time_start );
	echo ' - ' . implode( ',', $has_cap );

	// Test two
	$time_start = microtime( true );

  // Check user roles against a list, return after first one
	function current_user_can_array( $list ) {
		foreach ( $list as $cap ) {
			if ( current_user_can( $cap ) ) {
				return $cap;
			}
		}

		return false;
	}

	$has_cap = current_user_can_array( $check_list_of_caps );

	// end test 2
	$time_end = microtime( true );

	echo '<br /><b>Total Execution Time test 2:</b> ' . ( $time_end - $time_start );
	echo ' - ' . $has_cap;
	die();
});

First approach is always almost twice quicker :

• allcaps with native php functions : 4.39E-5 - manage_options
• current_user_can with a foreach loop : 7.09E-5 - manage_options

It is due to the fact that natives php functions, especially for arrays, are made in deep languages (C& C++), which is quicker.