Solve fatal error on credit memo mail

[arnoudhgz]

Also insert the correct item for invoice mail, to calculate the appropriate subtotal on row item.

This is an addition of PR #22265 where the subtotal for creditmemo should be fixed. Now this same strategy is chosen for the invoice mail and the fatal error caused by this previous PR is solved.

By checking the type instance of $item I tried to keep it as strict as possible while keeping code the change as simple as possible.

Fixed Issues (if relevant)

1. Fatal error on creditmemo mail grouped product #25617: Fatal error on creditmemo mail grouped product

Manual testing scenarios (*)

1. Add grouped product to cart, make sure to have for one item 3 products.
2. Place order.
3. In the backend create invoice for this order, nb make sure to invoice only 2 of the 3 products (update qty)
4. Send invoice mail, see that the subtotal is correct
5. In the backend create credit memo for this same order, nb make sure to only credit 1 product (update qty)
6. Send credit memo mail, see that the subtotal is correct.

Contribution checklist (*)

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/integration tests (if applicable)
• All automated tests passed successfully (all builds are green)

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[arnoudhgz]

@joni-jones the CLA is in progress by someone from my company. Can you advice me on the Semantic Version Checker failure?

[arnoudhgz]

@sidolov / @joni-jones can you advice me on the Semantic Version checker? All other checks are passed.

[ihor-sviziev]

Hi @arnoudhgz,
I just looked on your fix - for sure it should work, however it looks like class app/code/Magento/Sales/Block/Order/Email/Items/Order/DefaultOrder.php is designed for rendering order items, so this issue is wider - looks like incorrect block is used for rendering invoice and credit memo items.

Could you investigate why it tries to use this block for rendering credit memo and invoice items and adjust your solution?

[ihor-sviziev]

Hi @arnoudhgz,
Will you be able to update your PR?

[arnoudhgz]

@ihor-sviziev at the moment I do not have the time to investigate the wider issue about the wrong class usage. I don't know if it is actually wrong since the items are rendered from the related order...

But the related ticket is closed, so maybe it is already differently solved in the code?

[ihor-sviziev]

Hi @arnoudhgz,
Yeah, I see that related issue was already closed.
So I'm closing this PR as issue isn't reproducing anymore.

Thank you for your contribution!

[m2-assistant]

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