@jasonbahl Will there be any love given to this one anytime soon? :)

@HumidBrains @jasonbahl
I discovered the same problem in our project, and it seems like its the graphql_acf_post_object_source filter that wp-graphql-woocommerce uses and returns wrong value.

File includes/class-acf-schema-filters.php line 56.

public static function resolve_post_object_source( $source, $value ) {
	$post = get_post( $value );
	if ( $post instanceof \WP_Post ) {
		switch ( $post->post_type ) {
			case 'shop_coupon':
				$source = new Coupon( $post->ID );
				break;
			case 'shop_order':
				$source = new Order( $post->ID );
				break;
			case 'product':
				$source = new Product( $post->ID );
				break;
		}
	}

	return $source;
}

Since the Post Object field can return both null and an array this code wont work because when querying a single product get_post returns itself, and the code has no support for an array.

having the same issue

versions:
WP 5.8.1
Woo 5.8.0
Graphql 1.6.5
WPGraphQL WooCommerce 0.10.4
Advanced Custom Fields PRO 5.10.2
WPGraphQL for Advanced Custom Fields 0.5.3

Steps:

I'm having a CPT - Auctions
Auction has an ACF Relationship field with Products
when I'm running the following query - I'm receiving an error

QUERY

ERROR

This is a pretty old issue, but it typically occurred when there were orphaned IDs stored as values for ACF Fields.

WPGraphQL for ACF has been re-built over here: https://github.com/wp-graphql/wpgraphql-acf and relational fields are all now using connections and WPGraphQL DataLoaders which account for issues like orphaned IDs not throwing errors.

I recommend switching to the new version of WPGraphQL for ACF at your earliest convenience as it's the version we'll be releasing on WordPress.org and supporting long-term.