Show donations made via PMPro Donations Add-On on a separate line on the PMPro Invoice and Email Invoice sent

my_pmpro_donations_separate_example_gist.php

<?php // do not copy this line

// Copy from below here...

/**
 * Example of how to use pmpro_get_price_parts filter alongside PMPro Donations
 * 
 * You can add this recipe to your site by creating a custom plugin
 * or using the Code Snippets plugin available for free in the WordPress repository.
 * Read this companion article for step-by-step directions on either method.
 * https://www.paidmembershipspro.com/create-a-plugin-for-pmpro-customizations/
 */

function my_custom_get_price_parts( $price_parts, $invoice ) {
	if ( ! function_exists( 'pmprodon_get_price_components' ) ) {
		// PMPro donations not installed.
		return;
	}
	$donation_price_components = pmprodon_get_price_components( $invoice );

	$subtotal                  = $invoice->total;
	$donation_amount           = floatval( $donation_price_components['donation'] );
	$membership_amount         = $subtotal - $donation_amount;

	$price_parts[ 'subtotal' ] = array(
		'label' => 'Subtotal',
		'value' => pmpro_escape_price( pmpro_formatPrice( $subtotal ) ),
	);
	$price_parts[ 'sub_element_membership' ] = array(
		'label' => 'Membership Price',
		'value' => pmpro_escape_price( pmpro_formatPrice( $membership_amount ) ),
	);
	$price_parts[ 'sub_element_donation' ] = array(
		'label' => 'Donation',
		'value' => pmpro_escape_price( pmpro_formatPrice( $donation_amount ) ),
	);
  
	return $price_parts;
}

add_filter( 'pmpro_get_price_parts', 'my_custom_get_price_parts', 10, 2 );