[5.x]: InvalidConfigException when calling toArray() on custom line item

[jmauzyk]

What happened?

Description

Getting the following error when calling toArray() on a custom line item:

yii\base\InvalidConfigException: Cannot get a purchasable for a custom line item in /var/www/html/vendor/craftcms/commerce/src/models/LineItem.php:838

Steps to reproduce

1. Create a custom line item object.
2. Call toArray() on the line item object.

Expected behavior

Return a serialized representation of the custom line item object.

Actual behavior

Throws an InvalidConfigException.

Craft CMS version

Craft Pro 5.10.10

Craft Commerce version

5.6.7

PHP version

8.2.30

Operating system and version

Linux 6.12.76-linuxkit

Database type and version

PostgreSQL 14.20

Image driver and version

Imagick 3.8.1 (ImageMagick 7.1.1-43)

Installed plugins and versions

No response

[linear-code]

COM-592

[jmauzyk]

Sorry, realized after posting that I need to qualify this a bit. The exception can occur when calling toArray() in conjunction with extraFields() on a custom line item.

The specific instance in which I encountered this was when using craft\web\View::renderObjectTemplate() to render a template with a custom line item as the object. It serializes the object with extraFields() prior to rendering. Because the array returned by extraFields() always includes purchasable regardless of whether the line item is custom or not, this can result in getPurchasable() being called during serialization of a custom line item, which then throws the exception.

[nfourtythree]

Hi @jmauzyk

Thank you for reporting this. The extra information was really helpful to understand the issue and what you were trying to achieve.

It was possible to replicate the issue in the scenario you mentioned.

We are looking into a fix for this which you can follow here: #4340

For now is it possible to conditionally use two different render templates for what you are trying to do? One for purchasable line items that has purchasable in it and one for custom line items that doesn't?

Or does that not work in your project's workflow?

Thanks!

[jmauzyk]

Hi @nfourtythree,

My use case is for settings in a private plugin that integrates with our shipping software. The settings can define Twig template strings that define how certain properties are output for requests to the shipping API. For example, I was trying to use
{{ object.type.value != 'custom' ? object.purchasable.product.shipSeparate : false }}
to define whether a line item should be packed separately or not.

So I think two different templates wouldn't work well in this case, at least not without changing the settings schema. I could use craft\web\View::renderString(), but that would have the slight downside of losing the convenience of being able to use short output like {myCustomField} instead of having to access through dot notation on a named object.

Thanks!