Guard against crashes when only an entity's interface is known

src/Rules/Doctrine/ORM/RepositoryMethodCallRule.php

@@ -60,6 +60,10 @@ public function processNode(Node $node, Scope $scope): array
 		}
 		$entityClass = $entityClassType->getClassName();
 
+		if (interface_exists($entityClass)) {
+			return [];
+		}
+
 		$methodNameIdentifier = $node->name;
 		if (!$methodNameIdentifier instanceof Node\Identifier) {
 			return [];

tests/Rules/Doctrine/ORM/EntityImplementingInterfaceTest.php

@@ -0,0 +1,38 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Doctrine\ORM;
+
+use PHPStan\Rules\Rule;
+use PHPStan\Testing\RuleTestCase;
+use PHPStan\Type\Doctrine\ObjectMetadataResolver;
+
+/**
+ * @extends RuleTestCase<RepositoryMethodCallRule>
+ */
+class EntityImplementingInterfaceTest extends RuleTestCase
+{
+
+	protected function getRule(): Rule
+	{
+		return new RepositoryMethodCallRule(new ObjectMetadataResolver($this->createReflectionProvider(), __DIR__ . '/entity-manager.php', null));
+	}
+
+	/**
+	 * @return string[]
+	 */
+	public static function getAdditionalConfigFiles(): array
+	{
+		return [__DIR__ . '/magic-repository.neon'];
+	}
+
+	public function testRule(): void
+	{
+		$this->analyse([__DIR__ . '/data/repository-findBy-interface.php'], [
+			[
+				'Call to method Doctrine\ORM\EntityRepository<PHPStan\Rules\Doctrine\ORM\MyEntityImplementingInterface>::findBy() - entity PHPStan\Rules\Doctrine\ORM\MyEntityImplementingInterface does not have a field named $nonexistent.',
+				22,
+			],
+		]);
+	}
+
+}

tests/Rules/Doctrine/ORM/data/MyEntityImplementingInterface.php

@@ -0,0 +1,31 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Doctrine\ORM;
+
+use Doctrine\ORM\Mapping as ORM;
+
+/**
+ * @ORM\Entity()
+ */
+class MyEntityImplementingInterface implements MyInterface
+{
+	/**
+	 * @ORM\Id()
+	 * @ORM\GeneratedValue()
+	 * @ORM\Column(type="integer")
+	 *
+	 * @var int
+	 */
+	private $id;
+
+	/**
+	 * @ORM\Column()
+	 * @var string
+	 */
+	private $name;
+
+	public function getName(): string
+	{
+		return $this->name;
+	}
+}

tests/Rules/Doctrine/ORM/data/MyInterface.php

@@ -0,0 +1,8 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Doctrine\ORM;
+
+interface MyInterface
+{
+	public function getName(): string;
+}

tests/Rules/Doctrine/ORM/data/repository-findBy-interface.php

@@ -0,0 +1,36 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Rules\Doctrine\ORM;
+
+use Doctrine\ORM\EntityManager;
+
+class RepositoryForInterfaceFindByCalls
+{
+
+	/** @var EntityManager */
+	private $entityManager;
+
+	public function __construct(EntityManager $entityManager)
+	{
+		$this->entityManager = $entityManager;
+	}
+
+	public function doFindByWithConcreteClass(): void
+	{
+		$entityRepository = $this->entityManager->getRepository(MyEntityImplementingInterface::class);
+		$entityRepository->findBy(['id' => 1]);
+		$entityRepository->findBy(['nonexistent' => 'test']);
+	}
+
+	public function doFindByWithInterface(MyInterface $entity): void
+	{
+		$entityRepository = $this->entityManager->getRepository(get_class($entity));
+		// This is likely to work, but cannot be inferred from the interface
+		// alone
+		$repo->findBy(['name' => $entity->getName()]);
+		// This is NOT likely to work, but can't be proven without examining
+		// all implementations of the interface
+		$entityRepository->findBy(['nonexistent' => 'test']);
+	}
+
+}