diff --git a/tests/Doctrine/Tests/ORM/Utility/HierarchyDiscriminatorResolverTest.php b/tests/Doctrine/Tests/ORM/Utility/HierarchyDiscriminatorResolverTest.php
new file mode 100644
index 000000000..cffb8cd3b
--- /dev/null
+++ b/tests/Doctrine/Tests/ORM/Utility/HierarchyDiscriminatorResolverTest.php
@@ -0,0 +1,56 @@
+<?php
+
+namespace Doctrine\Tests\ORM\Utility;
+
+use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\Mapping\ClassMetadata;
+use Doctrine\ORM\Utility\HierarchyDiscriminatorResolver;
+use PHPUnit\Framework\TestCase;
+use Prophecy\Argument;
+
+class HierarchyDiscriminatorResolverTest extends TestCase
+{
+    public function testResolveDiscriminatorsForClass()
+    {
+        $childClassMetadata = new ClassMetadata('ChildEntity');
+        $childClassMetadata->name = 'Some\Class\Child\Name';
+        $childClassMetadata->discriminatorValue = 'child-discriminator';
+        
+        $classMetadata = new ClassMetadata('Entity');
+        $classMetadata->subClasses = [$childClassMetadata->name];
+        $classMetadata->name = 'Some\Class\Name';
+        $classMetadata->discriminatorValue = 'discriminator';
+
+        $em = $this->prophesize(EntityManagerInterface::class);
+        $em->getClassMetadata($classMetadata->name)
+            ->shouldBeCalled()
+            ->willReturn($classMetadata);
+        $em->getClassMetadata($childClassMetadata->name)
+            ->shouldBeCalled()
+            ->willReturn($childClassMetadata);
+
+        $discriminators = HierarchyDiscriminatorResolver::resolveDiscriminatorsForClass($classMetadata, $em->reveal());
+        
+        $this->assertCount(2, $discriminators);
+        $this->assertArrayHasKey($classMetadata->discriminatorValue, $discriminators);
+        $this->assertArrayHasKey($childClassMetadata->discriminatorValue, $discriminators);
+    }
+
+    public function testResolveDiscriminatorsForClassWithNoSubclasses()
+    {
+        $classMetadata = new ClassMetadata('Entity');
+        $classMetadata->subClasses = [];
+        $classMetadata->name = 'Some\Class\Name';
+        $classMetadata->discriminatorValue = 'discriminator';
+
+        $em = $this->prophesize(EntityManagerInterface::class);
+        $em->getClassMetadata($classMetadata->name)
+            ->shouldBeCalled()
+            ->willReturn($classMetadata);
+
+        $discriminators = HierarchyDiscriminatorResolver::resolveDiscriminatorsForClass($classMetadata, $em->reveal());
+        
+        $this->assertCount(1, $discriminators);
+        $this->assertArrayHasKey($classMetadata->discriminatorValue, $discriminators);
+    }
+}