MAGETWO-29334: Impossible to save existent Grouped Product with no child items

Author: Maksym Aposov

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

@@ -5,6 +5,8 @@
  */
 namespace Magento\GroupedProduct\Model\Product\Initialization\Helper\ProductLinks\Plugin;
 
+use Magento\GroupedProduct\Model\Product\Type\Grouped as TypeGrouped;
+
 class Grouped
 {
     /**
@@ -22,8 +24,9 @@ public function beforeInitializeLinks(
         \Magento\Catalog\Model\Product $product,
         array $links
     ) {
-        if (isset($links['associated']) && !$product->getGroupedReadonly()) {
-            $product->setGroupedLinkData((array)$links['associated']);
+        if ($product->getTypeId() == TypeGrouped::TYPE_CODE && !$product->getGroupedReadonly()) {
+            $links = isset($links['associated']) ? $links['associated'] : [];
+            $product->setGroupedLinkData($links);
         }
     }
 }

app/code/Magento/GroupedProduct/Test/Unit/Model/Product/Initialization/Helper/ProductLinks/Plugin/GroupedTest.php

@@ -6,6 +6,8 @@
  */
 namespace Magento\GroupedProduct\Test\Unit\Model\Product\Initialization\Helper\ProductLinks\Plugin;
 
+use Magento\GroupedProduct\Model\Product\Type\Grouped;
+use Magento\Catalog\Model\Product\Type;
 
 class GroupedTest extends \PHPUnit_Framework_TestCase
 {
@@ -15,20 +17,20 @@ class GroupedTest extends \PHPUnit_Framework_TestCase
     protected $model;
 
     /**
-     * @var \PHPUnit_Framework_MockObject_MockObject
+     * @var \Magento\Catalog\Model\Product|\PHPUnit_Framework_MockObject_MockObject
      */
     protected $productMock;
 
     /**
-     * @var \PHPUnit_Framework_MockObject_MockObject
+     * @var \Magento\Catalog\Model\Product\Initialization\Helper\ProductLinks|\PHPUnit_Framework_MockObject_MockObject
      */
     protected $subjectMock;
 
     protected function setUp()
     {
         $this->productMock = $this->getMock(
             'Magento\Catalog\Model\Product',
-            ['getGroupedReadonly', 'setGroupedLinkData', '__wakeup'],
+            ['getGroupedReadonly', 'setGroupedLinkData', '__wakeup', 'getTypeId'],
             [],
             '',
             false
@@ -43,22 +45,49 @@ protected function setUp()
         $this->model = new \Magento\GroupedProduct\Model\Product\Initialization\Helper\ProductLinks\Plugin\Grouped();
     }
 
-    public function testBeforeInitializeLinksRequestDoesNotHaveGrouped()
+    /**
+     * @dataProvider productTypeDataProvider
+     */
+    public function testBeforeInitializeLinksRequestDoesNotHaveGrouped($productType)
     {
+        $this->productMock->expects($this->once())->method('getTypeId')->will($this->returnValue($productType));
         $this->productMock->expects($this->never())->method('getGroupedReadonly');
         $this->productMock->expects($this->never())->method('setGroupedLinkData');
         $this->model->beforeInitializeLinks($this->subjectMock, $this->productMock, []);
     }
 
-    public function testBeforeInitializeLinksRequestHasGrouped()
+    public function productTypeDataProvider()
     {
+        return [
+            [Type::TYPE_SIMPLE],
+            [Type::TYPE_BUNDLE],
+            [Type::TYPE_VIRTUAL]
+        ];
+    }
+
+    /**
+     * @dataProvider linksDataProvider
+     */
+    public function testBeforeInitializeLinksRequestHasGrouped($linksData)
+    {
+        $this->productMock->expects($this->once())->method('getTypeId')->will($this->returnValue(Grouped::TYPE_CODE));
         $this->productMock->expects($this->once())->method('getGroupedReadonly')->will($this->returnValue(false));
-        $this->productMock->expects($this->once())->method('setGroupedLinkData')->with(['value']);
-        $this->model->beforeInitializeLinks($this->subjectMock, $this->productMock, ['associated' => 'value']);
+        $this->productMock->expects($this->once())->method('setGroupedLinkData')->with($linksData);
+        $this->model->beforeInitializeLinks($this->subjectMock, $this->productMock, ['associated' => $linksData]);
+    }
+
+    public function linksDataProvider()
+    {
+        return [
+            [['associated' => [5 => ['id' => '2', 'qty' => '100', 'position' => '1']]]],
+            [['associated' => []]],
+            [[]]
+        ];
     }
 
     public function testBeforeInitializeLinksProductIsReadonly()
     {
+        $this->productMock->expects($this->once())->method('getTypeId')->will($this->returnValue(Grouped::TYPE_CODE));
         $this->productMock->expects($this->once())->method('getGroupedReadonly')->will($this->returnValue(true));
         $this->productMock->expects($this->never())->method('setGroupedLinkData');
         $this->model->beforeInitializeLinks($this->subjectMock, $this->productMock, ['associated' => 'value']);