fix Can't remove samples link product downloadable

app/code/Magento/Downloadable/Model/Sample/UpdateHandler.php

@@ -43,10 +43,8 @@ public function __construct(SampleRepository $sampleRepository)
      */
     public function execute($entity, $arguments = []): ProductInterface
     {
-        $samples = $entity->getExtensionAttributes()->getDownloadableProductSamples();
-
-        if ($samples && $entity->getTypeId() === Type::TYPE_DOWNLOADABLE) {
-            $this->updateSamples($entity, $samples);
+        if ($entity->getTypeId() === Type::TYPE_DOWNLOADABLE) {
+            $this->updateSamples($entity);
         }
 
         return $entity;
@@ -56,20 +54,22 @@ public function execute($entity, $arguments = []): ProductInterface
      * Update product samples
      *
      * @param ProductInterface $entity
-     * @param array $samples
      * @return void
      */
-    private function updateSamples(ProductInterface $entity, array $samples): void
+    private function updateSamples(ProductInterface $entity): void
     {
         $isGlobalScope = (int) $entity->getStoreId() === self::GLOBAL_SCOPE_ID;
+        $samples = $entity->getExtensionAttributes()->getDownloadableProductSamples();
         $oldSamples = $this->sampleRepository->getList($entity->getSku());
 
-        $updatedSamples = [];
-        foreach ($samples as $sample) {
-            if ($sample->getId()) {
-                $updatedSamples[$sample->getId()] = true;
+        if (!empty($samples)) {
+            $updatedSamples = [];
+            foreach ($samples as $sample) {
+                if ($sample->getId()) {
+                    $updatedSamples[$sample->getId()] = true;
+                }
+                $this->sampleRepository->save($entity->getSku(), $sample, $isGlobalScope);
             }
-            $this->sampleRepository->save($entity->getSku(), $sample, $isGlobalScope);
         }
 
         foreach ($oldSamples as $sample) {

app/code/Magento/Downloadable/Test/Mftf/ActionGroup/RemoveSampleActionGroup.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ /**
+  * Copyright © Magento, Inc. All rights reserved.
+  * See COPYING.txt for license details.
+  */
+-->
+
+<actionGroups xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+              xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/actionGroupSchema.xsd">
+    <actionGroup name="RemoveSampleActionGroup">
+        <annotations>
+            <description>Delete Downloadable Product Sample by row id.</description>
+        </annotations>
+        <arguments>
+            <argument name="index" type="string" defaultValue="0"/>
+        </arguments>
+
+        <waitForElementVisible selector="{{AdminProductDownloadableSection.addSampleRemoveRowButton(index)}}" stepKey="waitForSample"/>
+        <click selector="{{AdminProductDownloadableSection.addSampleRemoveRowButton(index)}}" stepKey="deleteSample"/>
+    </actionGroup>
+</actionGroups>

app/code/Magento/Downloadable/Test/Mftf/ActionGroup/VerifySampleAbsentActionGroup.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ /**
+  * Copyright © Magento, Inc. All rights reserved.
+  * See COPYING.txt for license details.
+  */
+-->
+
+<actionGroups xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+              xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/actionGroupSchema.xsd">
+    <actionGroup name="VerifySampleAbsentActionGroup">
+        <annotations>
+            <description>Verify Samples are absent on Downloadable Product page.</description>
+        </annotations>
+        <arguments>
+            <argument name="index" type="string" defaultValue="0"/>
+        </arguments>
+
+        <dontSeeElement selector="{{AdminProductDownloadableSection.addSampleTitleInput(index)}}" stepKey="verifySamplesAbsent"/>
+    </actionGroup>
+</actionGroups>

app/code/Magento/Downloadable/Test/Mftf/ActionGroup/VerifySamplePresentActionGroup.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ /**
+  * Copyright © Magento, Inc. All rights reserved.
+  * See COPYING.txt for license details.
+  */
+-->
+
+<actionGroups xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+              xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/actionGroupSchema.xsd">
+    <actionGroup name="VerifySamplePresentActionGroup">
+        <annotations>
+            <description>Verify Sample is present on Downloadable Product page.</description>
+        </annotations>
+        <arguments>
+            <argument name="index" type="string" defaultValue="0"/>
+        </arguments>
+
+        <seeElement selector="{{AdminProductDownloadableSection.addSampleTitleInput(index)}}" stepKey="verifySampleVisible"/>
+    </actionGroup>
+</actionGroups>

app/code/Magento/Downloadable/Test/Mftf/Section/AdminProductDownloadableSection.xml

@@ -33,14 +33,13 @@
         <element name="addLinkSampleUrlInput" type="input" selector="input[name='downloadable[link][{{var1}}][sample][url]']" parameterized="true" />
         <element name="linkFileNameOrUrl" type="text" parameterized="true" selector="//div[@data-index='container_links']//tr[@data-repeat-index='{{index}}']//fieldset[@data-index='container_file']//div[@class='file-uploader-filename']//a|//input[@name='downloadable[link][{{index}}][link_url]']"/>
         <element name="linkSampleFileNameOrUrl" type="text" parameterized="true" selector="//div[@data-index='container_links']//tr[@data-repeat-index='{{index}}']//fieldset[@data-index='container_sample']//div[@class='file-uploader-filename']//a|//input[@name='downloadable[link][{{index}}][sample][url]']"/>
-
         <element name="samplesTitleInput" type="input" selector="input[name='product[samples_title]']"/>
         <element name="samplesAddLinkButton" type="button" selector="div[data-index='container_samples'] button[data-action='add_new_row']" />
 
         <!-- Parameterized selectors for elements in an individual sample row -->
         <element name="addSampleTitleInput" type="input" selector="input[name='downloadable[sample][{{var1}}][title]']" parameterized="true" />
         <element name="addSampleFileTypeSelector" type="select" selector="select[name='downloadable[sample][{{var1}}][type]']" parameterized="true" />
-        <element name="addSampleRemoveRowButton" type="button" selector="div[data-index='container_links'] tr[data-repeat-index='{{var1}}'] button[data-action='remove_row']" parameterized="true" />
+        <element name="addSampleRemoveRowButton" type="button" selector="div[data-index='container_samples'] tr[data-repeat-index='{{var1}}'] button[data-action='remove_row']" parameterized="true" />
         <element name="addSampleFileUploadFile" type="file" selector="div[data-index='container_samples'] tr[data-repeat-index='{{var1}}'] input[type='file']" parameterized="true" />
         <element name="addSampleFileUrlInput" type="input" selector="input[name='downloadable[sample][{{var1}}][sample_url]']" parameterized="true" />
         <element name="sampleFileNameOrUrl" type="text" parameterized="true" selector="//div[@data-index='sample']//tr[@data-repeat-index='{{index}}']//fieldset[@data-index='container_sample']//div[@class='file-uploader-filename']//a|//input[@name='downloadable[sample][{{index}}][sample_url]']"/>

app/code/Magento/Downloadable/Test/Mftf/Test/AdminDeleteDownloadableProductSampleTest.xml

@@ -0,0 +1,96 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ /**
+  * Copyright © Magento, Inc. All rights reserved.
+  * See COPYING.txt for license details.
+  */
+-->
+
+<tests xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/testSchema.xsd">
+    <test name="AdminDeleteDownloadableProductSampleTest">
+        <annotations>
+            <features value="Catalog"/>
+            <stories value="Delete Downloadable Product"/>
+            <title value="Delete Downloadable Product Samples"/>
+            <description value="Admin should be able to delete downloadable product samples"/>
+            <severity value="MAJOR"/>
+            <group value="Downloadable"/>
+        </annotations>
+        <before>
+            <magentoCLI command="downloadable:domains:add static.magento.com" stepKey="addDownloadableDomain"/>
+            <createData entity="SimpleSubCategory" stepKey="createCategory"/>
+            <actionGroup ref="AdminLoginActionGroup" stepKey="LoginAsAdmin"/>
+        </before>
+        <after>
+            <deleteData createDataKey="createCategory" stepKey="deleteCategory"/>
+            <actionGroup ref="DeleteProductUsingProductGridActionGroup" stepKey="deleteProduct">
+                <argument name="product" value="DownloadableProduct"/>
+            </actionGroup>
+            <actionGroup ref="AdminLogoutActionGroup" stepKey="logout"/>
+            <magentoCLI command="downloadable:domains:remove static.magento.com" stepKey="removeDownloadableDomain"/>
+        </after>
+
+        <!-- Create downloadable product -->
+        <actionGroup ref="AdminOpenProductIndexPageActionGroup" stepKey="amOnProductGridPage"/>
+        <actionGroup ref="GoToSpecifiedCreateProductPageActionGroup" stepKey="createProduct">
+            <argument name="productType" value="downloadable"/>
+        </actionGroup>
+
+        <!-- Fill downloadable product values -->
+        <actionGroup ref="FillMainProductFormNoWeightActionGroup" stepKey="fillDownloadableProductForm">
+            <argument name="product" value="DownloadableProduct"/>
+        </actionGroup>
+
+        <!-- Add downloadable product to category -->
+        <searchAndMultiSelectOption selector="{{AdminProductFormSection.categoriesDropdown}}"
+                                    parameterArray="[$$createCategory.name$$]" stepKey="fillCategory"/>
+
+        <!-- Fill downloadable link information before the creation link -->
+        <actionGroup ref="AdminAddDownloadableLinkInformationActionGroup" stepKey="addDownloadableLinkInformation"/>
+
+        <!-- Links can be purchased separately -->
+        <checkOption selector="{{AdminProductDownloadableSection.isLinksPurchasedSeparately}}"
+                     stepKey="checkOptionPurchaseSeparately"/>
+
+        <!-- Add downloadable link -->
+        <actionGroup ref="AddDownloadableProductLinkWithMaxDownloadsActionGroup" stepKey="addDownloadableProductLink">
+            <argument name="link" value="downloadableLinkWithMaxDownloads"/>
+        </actionGroup>
+
+        <!-- Add Sample File -->
+        <actionGroup ref="AddDownloadableSampleFileActionGroup" stepKey="addDownloadSampleFile">
+            <argument name="sample" value="downloadableSampleFile"/>
+        </actionGroup>
+
+        <!-- Add Sample Url -->
+        <actionGroup ref="AddDownloadableSampleUrlActionGroup" stepKey="addDownloadableSampleUrl">
+            <argument name="sample" value="downloadableSampleUrl"/>
+        </actionGroup>
+
+        <!-- Save product -->
+        <actionGroup ref="SaveProductFormActionGroup" stepKey="saveProduct"/>
+
+        <!-- Check if Samples are present -->
+        <actionGroup ref="VerifySamplePresentActionGroup" stepKey="verifySampleFilePresent">
+            <argument name="index" value="0"/>
+        </actionGroup>
+        <actionGroup ref="VerifySamplePresentActionGroup" stepKey="verifySampleUrlPresent">
+            <argument name="index" value="1"/>
+        </actionGroup>
+
+        <!-- Remove Samples -->
+        <actionGroup ref="RemoveSampleActionGroup" stepKey="removeSampleUrl">
+            <argument name="index" value="1"/>
+        </actionGroup>
+        <actionGroup ref="RemoveSampleActionGroup" stepKey="removeSampleFile">
+            <argument name="index" value="0"/>
+        </actionGroup>
+        <actionGroup ref="SaveProductFormActionGroup" stepKey="saveProductAfterSamplesRemoved"/>
+
+        <!-- Check if Samples are absent -->
+        <actionGroup ref="VerifySampleAbsentActionGroup" stepKey="verifySamplesAbsent">
+            <argument name="index" value="0"/>
+        </actionGroup>
+    </test>
+</tests>

app/code/Magento/Downloadable/Test/Unit/Model/Sample/UpdateHandlerTest.php

@@ -129,9 +129,6 @@ public function testExecuteNonDownloadable(): void
         $this->entityMock->expects($this->once())
             ->method('getTypeId')
             ->willReturn(Type::TYPE_DOWNLOADABLE . 'some');
-        $this->entityMock->expects($this->once())
-            ->method('getExtensionAttributes')
-            ->willReturn($this->productExtensionMock);
         $this->entityMock->expects($this->never())
             ->method('getSku');
         $this->entityMock->expects($this->never())

dev/tests/api-functional/testsuite/Magento/Downloadable/Api/ProductRepositoryTest.php

@@ -326,10 +326,8 @@ public function testUpdateDownloadableProductData(): void
         $response = $this->saveProduct($productData);
 
         $this->assertArrayHasKey(ProductInterface::EXTENSION_ATTRIBUTES_KEY, $response);
-        $this->assertArrayHasKey(self::PRODUCT_SAMPLES, $response[ProductInterface::EXTENSION_ATTRIBUTES_KEY]);
         $this->assertArrayHasKey(self::PRODUCT_LINKS, $response[ProductInterface::EXTENSION_ATTRIBUTES_KEY]);
 
-        $this->assertCount(2, $response[ProductInterface::EXTENSION_ATTRIBUTES_KEY][self::PRODUCT_SAMPLES]);
         $this->assertCount(2, $response[ProductInterface::EXTENSION_ATTRIBUTES_KEY][self::PRODUCT_LINKS]);
     }