Add checkout_cart_product_add_before event

[peterjaap]

As @markoshust blogged in 2012 (!), there is no checkout_cart_product_add_before event in Magento!

Even though there is a checkout_cart_product_add_after event. Now we're stuck with controller_action_predispatch_checkout_cart_add which of course does not catch all cases since there are multiple (custom) ways to add a product to the cart.

Best option now is to create a plugin, but an event would be nicer.

Preconditions

1. Magento 2 code

Steps to reproduce

1. Observe \Magento\Checkout\Model\Cart::addProduct

Expected result

1. Events checkout_cart_product_add_before and checkout_cart_product_add_after are dispatched.

Actual result

1. Only checkout_cart_product_add_after event is dispatched.

[magento-engcom-team]

Hi @peterjaap. Thank you for your report.
To help us process this issue please make sure that you provided the following information:

• Summary of the issue
• Information on your environment
• Steps to reproduce
• Expected and actual results

Please make sure that the issue is reproducible on the vanilla Magento instance following Steps to reproduce. To deploy vanilla Magento instance on our environment, please, add a comment to the issue:

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where {$VERSION} is version tags (starting from 2.2.0+) or develop branches (2.2-develop +).
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@peterjaap do you confirm that you was able to reproduce the issue on vanilla Magento instance following steps to reproduce?

• yes
• no

@peterjaap, thank you for your report.
We've acknowledged the issue and added to our backlog.