Missing Default Config in v7.2.0 Causes PHP Deprecated Error in explode()

[JkappenFlashpoint]

Issue Brief

After updating to Tweakwise Export v7.2.0, the new functionality:

Features:

• Optionally skip children by Composite Product Type (b648d9a)

introduces errors during feed generation due to the absence of a fallback value for the new config entry tweakwise/export/exclude_child_attributes.

Problem

In Model/Config.php, the following code attempts to explode a config value:

$data = explode(
    ',',
    $this->config->getValue(self::PATH_SKIP_CHILD_BY_COMPOSITE_TYPE, ScopeInterface::SCOPE_STORE, $store)
);

When updating to v7.2.0, there is no default value for this config entry. As a result, when explode is executed on a null value, it triggers a PHP error:

Deprecated: explode(): Passing null to parameter #2 ($string) of type string is deprecated

This forces users to manually save the core_config data after updating, which is unintuitive and may lead to unexpected errors if overlooked.

---

Environment

• PHP Version: 8.2
• Magento Version: 2.4.7-p3
• Magento Enterprise: No
• Tweakwise Export Version: v7.2.0
• Magento Deploy Mode: Production
• Third-party modules: N/A

---

Steps to Reproduce

1. Install Magento with the Tweakwise Export v7.1.0 module.
2. Ensure the Magento shop has some composite-type products (e.g., Configurable or Bundle products).
3. Upgrade to v7.2.0.
4. Attempt to generate a product feed without manually saving the config.
5. Observe the PHP error during execution.

---

Actual Result

• A PHP error occurs due to explode() receiving null instead of a string.

Deprecated: explode(): Passing null to parameter #2 ($string) of type string is deprecated

---

Expected Result

• The module should provide a fallback value for tweakwise/export/exclude_child_attributes to prevent errors.
• No manual saving of core_config data should be required after an update.

---

Suggested Fix

• Ensure getValue() provides a default value (e.g., an empty string '' or default attributes) before calling explode().
• Implement a configuration migration script to set a default value during installation.

$data = explode(
    ',',
    $this->config->getValue(self::PATH_SKIP_CHILD_BY_COMPOSITE_TYPE, ScopeInterface::SCOPE_STORE, $store) ?? ''
);

This would prevent the issue and make the upgrade process seamless.