ACP2E-3647: [CLOUD]: GraphQl error Internal server error placeOrder mutation

Author: soklymeach

app/code/Magento/SalesRuleGraphQl/Model/Resolver/Coupon.php

@@ -33,7 +33,7 @@ public function __construct(
      */
     public function resolve(Field $field, $context, ResolveInfo $info, ?array $value = null, ?array $args = null)
     {
-        if(isset($value['order_model'])) {
+        if (isset($value['order_model'])) {
             return ['code' => $value['order_model']->getCouponCode()];
         }
         if (!isset($value['discount_model'])) {

app/code/Magento/SalesRuleGraphQl/Test/Unit/Model/Resolver/CouponTest.php

@@ -0,0 +1,143 @@
+<?php
+/**
+ * Copyright 2025 Adobe
+ * All Rights Reserved.
+ */
+declare(strict_types=1);
+
+namespace Magento\SalesRuleGraphQl\Test\Unit\Model\Resolver;
+
+use Magento\Framework\Exception\LocalizedException;
+use Magento\Framework\GraphQl\Config\Element\Field;
+use Magento\Framework\GraphQl\Schema\Type\ResolveInfo;
+use Magento\Quote\Api\Data\CartInterface;
+use Magento\SalesRule\Api\Data\CouponInterface;
+use Magento\SalesRule\Api\Data\RuleDiscountInterface;
+use Magento\SalesRule\Model\GetCoupons;
+use Magento\Sales\Api\Data\OrderInterface;
+use Magento\SalesRule\Model\Quote\GetCouponCodes;
+use Magento\SalesRuleGraphQl\Model\Resolver\Coupon;
+use PHPUnit\Framework\TestCase;
+
+class CouponTest extends TestCase
+{
+    /**
+     * @var GetCouponCodes|MockObject
+     */
+    private $getCouponCodesMock;
+
+    /**
+     * @var GetCoupons|MockObject
+     */
+    private $getCouponsMock;
+
+    /**
+     * @var Coupon|MockObject
+     */
+    private $resolver;
+
+    protected function setUp(): void
+    {
+        $this->getCouponCodesMock = $this->createMock(GetCouponCodes::class);
+        $this->getCouponsMock = $this->createMock(GetCoupons::class);
+        $this->resolver = new Coupon(
+            $this->getCouponCodesMock,
+            $this->getCouponsMock
+        );
+    }
+
+    public function testResolveWithOrderModel(): void
+    {
+        $orderModel = $this->createMock(OrderInterface::class);
+        $orderModel->expects($this->once())
+            ->method('getCouponCode')
+            ->willReturn('TEST1234');
+        $result = $this->resolver->resolve(
+            $this->createMock(Field::class),
+            [],
+            $this->createMock(ResolveInfo::class),
+            ['order_model' => $orderModel]
+        );
+
+        $this->assertEquals(['code' => 'TEST1234'], $result);
+    }
+
+    public function testResolveWithoutDiscountModel(): void
+    {
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage('"discount_model" value should be specified');
+        $this->resolver->resolve(
+            $this->createMock(Field::class),
+            [],
+            $this->createMock(ResolveInfo::class),
+            []
+        );
+    }
+
+    public function testResolveWithoutQuoteModel(): void
+    {
+        $this->expectException(LocalizedException::class);
+        $this->expectExceptionMessage('"quote_model" value should be specified');
+        $this->resolver->resolve(
+            $this->createMock(Field::class),
+            [],
+            $this->createMock(ResolveInfo::class),
+            ['discount_model' => $this->createMock(RuleDiscountInterface::class)]
+        );
+    }
+
+    public function testResolveWithoutCoupon(): void
+    {
+        $quoteModel = $this->createMock(CartInterface::class);
+        $discountModel = $this->createMock(RuleDiscountInterface::class);
+        $this->getCouponCodesMock->method('execute')->willReturn([]);
+        $this->getCouponsMock->method('execute')->willReturn([]);
+        $result = $this->resolver->resolve(
+            $this->createMock(Field::class),
+            [],
+            $this->createMock(ResolveInfo::class),
+            ['discount_model' => $discountModel, 'quote_model' => $quoteModel]
+        );
+
+        $this->assertNull($result);
+    }
+
+    public function testResolveWithMatchingRuleId(): void
+    {
+        $quoteModel = $this->createMock(CartInterface::class);
+        $discountModel = $this->createMock(RuleDiscountInterface::class);
+        $discountModel->method('getRuleID')->willReturn(123);
+        $couponMock = $this->createMock(CouponInterface::class);
+        $couponMock->method('getRuleId')->willReturn(123);
+        $couponMock->method('getCode')->willReturn('TEST1234');
+        $this->getCouponCodesMock->method('execute')->willReturn(['test']);
+        $this->getCouponsMock->method('execute')->willReturn([$couponMock]);
+        $result = $this->resolver->resolve(
+            $this->createMock(Field::class),
+            [],
+            $this->createMock(ResolveInfo::class),
+            ['discount_model' => $discountModel, 'quote_model' => $quoteModel]
+        );
+
+        $this->assertEquals(['code' => 'TEST1234'], $result);
+    }
+
+    public function testResolveNoMatchingRuleId(): void
+    {
+        $quoteModel = $this->createMock(CartInterface::class);
+        $discountModel = $this->createMock(RuleDiscountInterface::class);
+        $discountModel->method('getRuleID')->willReturn(123);
+        $couponMock = $this->createMock(CouponInterface::class);
+        $couponMock->method('getRuleId')->willReturn(321);
+        $this->getCouponCodesMock->method('execute')->willReturn(['test']);
+        $this->getCouponsMock->method('execute')->willReturn([$couponMock]);
+        $result = $this->resolver->resolve(
+            $this->createMock(Field::class),
+            [],
+            $this->createMock(ResolveInfo::class),
+            ['discount_model' => $discountModel, 'quote_model' => $quoteModel]
+        );
+
+        $this->assertNull($result);
+    }
+}