ENGCOM-2987: Add checkout_cart_product_add_before event #17830 #18080

 - Merge Pull Request #18080 from leandro-rosa/magento2:17830
 - Merged commits:
   1. 7b728b1
   2. f9389ad
   3. fef2205
   4. 0de795a

Author: magento-engcom-team

app/code/Magento/Checkout/Model/Cart.php

@@ -380,6 +380,10 @@ public function addProduct($productInfo, $requestInfo = null)
             }
 
             try {
+                $this->_eventManager->dispatch(
+                    'checkout_cart_product_add_before',
+                    ['info' => $requestInfo, 'product' => $product]
+                );
                 $result = $this->getQuote()->addProduct($product, $request);
             } catch (\Magento\Framework\Exception\LocalizedException $e) {
                 $this->_checkoutSession->setUseNotice(false);
@@ -615,6 +619,8 @@ public function truncate()
     }
 
     /**
+     * Get product ids.
+     *
      * @return int[]
      */
     public function getProductIds()

app/code/Magento/Checkout/Test/Unit/Model/CartTest.php

@@ -318,14 +318,20 @@ public function testAddProduct($productInfo, $requestInfo)
         $this->productRepository->expects($this->any())
             ->method('getById')
             ->will($this->returnValue($product));
+
+        $this->eventManagerMock->expects($this->at(0))->method('dispatch')->with(
+            'checkout_cart_product_add_before',
+            ['info' => $requestInfo, 'product' => $product]
+        );
+
         $this->quoteMock->expects($this->once())
         ->method('addProduct')
         ->will($this->returnValue(1));
         $this->checkoutSessionMock->expects($this->once())
             ->method('getQuote')
             ->will($this->returnValue($this->quoteMock));
 
-        $this->eventManagerMock->expects($this->at(0))->method('dispatch')->with(
+        $this->eventManagerMock->expects($this->at(1))->method('dispatch')->with(
             'checkout_cart_product_add_after',
             ['quote_item' => 1, 'product' => $product]
         );
@@ -363,17 +369,19 @@ public function testAddProductException()
         $this->productRepository->expects($this->any())
             ->method('getById')
             ->will($this->returnValue($product));
+
+        $this->eventManagerMock->expects($this->once())->method('dispatch')->with(
+            'checkout_cart_product_add_before',
+            ['info' => 4, 'product' => $product]
+        );
+
         $this->quoteMock->expects($this->once())
             ->method('addProduct')
             ->will($this->returnValue('error'));
         $this->checkoutSessionMock->expects($this->once())
             ->method('getQuote')
             ->will($this->returnValue($this->quoteMock));
 
-        $this->eventManagerMock->expects($this->never())->method('dispatch')->with(
-            'checkout_cart_product_add_after',
-            ['quote_item' => 1, 'product' => $product]
-        );
         $this->expectException(\Magento\Framework\Exception\LocalizedException::class);
         $this->cart->addProduct(4, 4);
     }
@@ -399,6 +407,11 @@ public function testAddProductExceptionBadParams()
             ->method('getById')
             ->will($this->returnValue($product));
 
+        $this->eventManagerMock->expects($this->never())->method('dispatch')->with(
+            'checkout_cart_product_add_before',
+            ['info' => 'bad', 'product' => $product]
+        );
+
         $this->eventManagerMock->expects($this->never())->method('dispatch')->with(
             'checkout_cart_product_add_after',
             ['quote_item' => 1, 'product' => $product]