Prevent form validation / submission when a line item delete button is clicked at /cart

Why shouldn't it trigger validation? It's a submit button on the form, and if someone changes a quantity on another line item I wouldn't want their value to be lost by removing something else in the cart. So I'd say this is by design, but if you had a rationale for the change I'd be happy to entertain it.

Obviously, if this were just a delete button at the bottom of a line item entity form, we'd want it to limit validation errors. But as just one element of many on a form, I don't see why we would. I may be misunderstanding the form, though - perhaps it's using a button level submit handler so quantity values wouldn't be saved anyways?

Ahh, interesting. It's how the "Checkout" button works, too.

Rerolled patch against dev.

I'm still not sure I understand this change unless we introduce #ajax functionality to allow a delete button to be clicked without other data loss on the form. My observation about this being a compound form vs. a single item form still informs my opinion here - I don't think we can expect people to only make one update related operation at a time (i.e. delete vs. a quantity change vs. whatever else someone might put in this form).

My mistake. Didn't watch the debug data close enough and got mixed up with another module.

And this patch seems to work.

+1 for some change to this behavior.

My use-case is:

Checkout form (at checkout/<order-num>/checkout) with a Delete button and no Quantity column in the line items. Only 1 of any item can be purchased, so Quantity isn't applicable.

Clicking Delete causes the form to throw validation errors b/c the billing information is empty.

For me, looks like the Delete button is actually triggering form submission and checkout completion.

IOW, after completing the billing information fields to sidestep the validation problem, hitting the Delete button submits the form, completes the checkout and purchases the item which should have been deleted.

To me, that's a bug...

Regardless of whether or not the user information is lost when this button is clicked, I don't think this button should trigger checkout. There are special handlers for other buttons to avoid processing orders (commerce_checkout_form_back_submit(), commerce_checkout_form_cancel_submit()) -- it seems this button needs one as well.