magento-test/app/code/Magento/GroupedProduct/etc/di.xml

<?xml version="1.0"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
    <preference for="Magento\GroupedProduct\Api\Data\GroupedOptionsInterface" type="Magento\GroupedProduct\Model\Quote\Item\GroupedOptions" />

    <type name="Magento\Quote\Model\Quote\Item\RelatedProducts">
        <arguments>
            <argument name="relatedProductTypes" xsi:type="array">
                <item name="grouped" xsi:type="const">Magento\GroupedProduct\Model\Product\Type\Grouped::TYPE_CODE</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\Product\LinkTypeProvider">
        <arguments>
            <argument name="linkTypes" xsi:type="array">
                <item name="associated" xsi:type="const">Magento\GroupedProduct\Model\ResourceModel\Product\Link::LINK_TYPE_GROUPED</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Sales\Model\ResourceModel\Report\Bestsellers">
        <arguments>
            <argument name="ignoredProductTypes" xsi:type="array">
                <item name="grouped" xsi:type="const">Magento\GroupedProduct\Model\Product\Type\Grouped::TYPE_CODE</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\Product\CatalogPrice">
        <arguments>
            <argument name="priceModelPool" xsi:type="array">
                <item name="grouped" xsi:type="string">Magento\GroupedProduct\Model\Product\CatalogPrice</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\Product\Type">
        <plugin name="grouped_output" type="Magento\GroupedProduct\Model\Product\Type\Plugin" />
    </type>
    <type name="Magento\Catalog\Model\Product\CartConfiguration">
        <plugin name="isProductConfigured" type="Magento\GroupedProduct\Model\Product\Cart\Configuration\Plugin\Grouped" />
    </type>
    <type name="Magento\Catalog\Helper\Product\Configuration">
        <plugin name="grouped_options" type="Magento\GroupedProduct\Helper\Product\Configuration\Plugin\Grouped"/>
    </type>
    <virtualType name="Magento\GroupedProduct\Pricing\Price\Pool" type="Magento\Framework\Pricing\Price\Pool">
        <arguments>
            <argument name="prices" xsi:type="array">
                <item name="final_price" xsi:type="string">Magento\GroupedProduct\Pricing\Price\FinalPrice</item>
                <item name="configured_price" xsi:type="string">Magento\GroupedProduct\Pricing\Price\ConfiguredPrice</item>
                <item name="configured_regular_price" xsi:type="string">Magento\GroupedProduct\Pricing\Price\ConfiguredRegularPrice</item>
            </argument>
            <argument name="target" xsi:type="object">Magento\Catalog\Pricing\Price\Pool</argument>
        </arguments>
    </virtualType>
    <virtualType name="Magento\GroupedProduct\Pricing\Price\Collection" type="Magento\Framework\Pricing\Price\Collection">
        <arguments>
            <argument name="pool" xsi:type="object">Magento\GroupedProduct\Pricing\Price\Pool</argument>
        </arguments>
    </virtualType>
    <type name="Magento\Framework\Pricing\PriceInfo\Factory">
        <arguments>
            <argument name="types" xsi:type="array">
                <item name="grouped" xsi:type="array">
                    <item name="infoClass" xsi:type="string">Magento\Framework\Pricing\PriceInfo\Base</item>
                    <item name="prices" xsi:type="string">Magento\GroupedProduct\Pricing\Price\Collection</item>
                </item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\ProductLink\CollectionProvider">
        <arguments>
            <argument name="providers" xsi:type="array">
                <item name="associated" xsi:type="object">Magento\GroupedProduct\Model\Product\Link\CollectionProvider\Grouped</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\Product\Initialization\Helper\ProductLinks">
        <plugin name="GroupedProduct" type="Magento\GroupedProduct\Model\Product\Initialization\Helper\ProductLinks\Plugin\Grouped" />
    </type>
    <type name="Magento\Catalog\Model\ResourceModel\Product\Link">
        <plugin name="groupedProductLinkProcessor" type="Magento\GroupedProduct\Model\ResourceModel\Product\Link\RelationPersister" />
    </type>
    <type name="Magento\Catalog\Model\ProductLink\Converter\ConverterPool">
        <arguments>
            <argument name="converters" xsi:type="array">
                <item name="associated" xsi:type="object">\Magento\GroupedProduct\Model\Product\Link\ProductEntity\Converter</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\ResourceModel\Product\Indexer\Price\BatchSizeCalculator">
        <arguments>
            <argument name="estimators" xsi:type="array">
                <item name="grouped" xsi:type="object">Magento\Catalog\Model\Indexer\Price\CompositeProductBatchSizeManagement</item>
            </argument>
            <argument name="batchSizeAdjusters" xsi:type="array">
                <item name="grouped" xsi:type="object">Magento\Catalog\Model\ResourceModel\Product\Indexer\Price\CompositeProductBatchSizeAdjuster</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Catalog\Model\Product\Configuration\Item\ItemResolverComposite">
        <arguments>
            <argument name="itemResolvers" xsi:type="array">
                <item name="grouped" xsi:type="string">Magento\GroupedProduct\Model\Product\Configuration\Item\ItemProductResolver</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\Quote\Model\Quote\Item\Repository">
        <arguments>
            <argument name="cartItemProcessors" xsi:type="array">
                <item name="grouped" xsi:type="object">Magento\GroupedProduct\Model\Quote\Item\CartItemProcessor\Proxy</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\CatalogInventory\Observer\SaveInventoryDataObserver">
        <arguments>
            <argument name="parentItemProcessorPool" xsi:type="array">
                <item name="grouped" xsi:type="object"> Magento\GroupedProduct\Model\Inventory\ParentItemProcessor</item>
            </argument>
        </arguments>
    </type>
    <type name="Magento\CatalogInventory\Plugin\MassUpdateProductAttribute">
        <arguments>
            <argument name="parentItemProcessorPool" xsi:type="array">
                <item name="grouped" xsi:type="object"> Magento\GroupedProduct\Model\Inventory\ParentItemProcessor</item>
            </argument>
        </arguments>
    </type>
</config>