Grouped Product inconsistency with on sale

[WillBrubaker]

EXPLANATION OF THE ISSUE

If a child product of a grouped product is on sale, the parent (grouped) product gets a sale badge, however, if using the sale_products shortcode, the parent product is not displayed. I believe that the correct behaviour would be that the parent product would be displayed with the shortcode.

STEPS TO REPRODUCE THE ISSUE

1. A grouped product exists
2. At least one of the grouped product's child products is on sale
3. See that the parent product has a sale badge
4. See that the parent product is not output by the sale_products shortcode

SYSTEM STATUS

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[mikejolley]

This one is not going to change (for now). The sale badge reflects that of the children within the group and you can see it's dynamically done here:

woocommerce/includes/class-wc-product-grouped.php

Line 52 in a0822e6

public function is_on_sale( $context = 'view' ) {

No sale status is stored on the grouped product itself so there is nothing to query when getting sale_products via the shortcode.

We can get the children, but remember each child can be in multiple groups now so grabbing all grouped products and comparing them to the found children would be too inefficient.

This cannot be fixed until #14217 is in place enabling us to do a more efficient query. Let's revisit this once we have that table in place.