Update for pull request #17772 - now using SimpleDataObjectConverter::snakeCaseToUpperCamelCase to maintain uniformity, and catch an additional case where the same issue occurred

Author: Richard Aspden

app/code/Magento/Catalog/Model/ProductLink/Repository.php

@@ -10,6 +10,7 @@
 use Magento\Catalog\Api\Data\ProductLinkExtensionFactory;
 use Magento\Catalog\Model\Product\Initialization\Helper\ProductLinks as LinksInitializer;
 use Magento\Catalog\Model\Product\LinkTypeProvider;
+use Magento\Framework\Api\SimpleDataObjectConverter;
 use Magento\Framework\Exception\CouldNotSaveException;
 use Magento\Framework\Exception\NoSuchEntityException;
 use Magento\Framework\EntityManager\MetadataPool;
@@ -170,7 +171,7 @@ public function getList(\Magento\Catalog\Api\Data\ProductInterface $product)
                     foreach ($item['custom_attributes'] as $option) {
                         $name = $option['attribute_code'];
                         $value = $option['value'];
-                        $setterName = 'set'.str_replace('_', '', ucwords($name, '_'));
+                        $setterName = 'set' . SimpleDataObjectConverter::snakeCaseToUpperCamelCase($name);
                         // Check if setter exists
                         if (method_exists($productLinkExtension, $setterName)) {
                             call_user_func([$productLinkExtension, $setterName], $value);

app/code/Magento/GroupedProduct/Model/Product/Initialization/Helper/ProductLinks/Plugin/Grouped.php

@@ -8,6 +8,7 @@
 use Magento\Catalog\Api\Data\ProductLinkExtensionFactory;
 use Magento\Catalog\Api\Data\ProductLinkInterfaceFactory;
 use Magento\Catalog\Api\ProductRepositoryInterface;
+use Magento\Framework\Api\SimpleDataObjectConverter;
 use Magento\Framework\Exception\NoSuchEntityException;
 use Magento\GroupedProduct\Model\Product\Type\Grouped as TypeGrouped;
 
@@ -111,7 +112,7 @@ public function beforeInitializeLinks(
                     foreach ($linkRaw['custom_attributes'] as $option) {
                         $name = $option['attribute_code'];
                         $value = $option['value'];
-                        $setterName = 'set' . ucfirst($name);
+                        $setterName = 'set' . SimpleDataObjectConverter::snakeCaseToUpperCamelCase($name);
                         // Check if setter exists
                         if (method_exists($productLinkExtension, $setterName)) {
                             call_user_func([$productLinkExtension, $setterName], $value);