Add runtime validation that the discriminator map contains all entity classes, also abstract ones?

lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php

@@ -268,17 +268,18 @@ protected function validateRuntimeMetadata($class, $parent)
                     throw MappingException::missingDiscriminatorColumn($class->name);
                 }
 
+                if (! in_array($class->name, $class->discriminatorMap, true)) {
+                    throw MappingException::mappedClassNotPartOfDiscriminatorMap($class->name, $class->rootEntityName);
+                }
+
                 foreach ($class->subClasses as $subClass) {
                     if ((new ReflectionClass($subClass))->name !== $subClass) {
                         throw MappingException::invalidClassInDiscriminatorMap($subClass, $class->name);
                     }
                 }
             } else {
                 assert($parent instanceof ClassMetadataInfo); // https://github.com/doctrine/orm/issues/8746
-                if (
-                    ! $class->reflClass->isAbstract()
-                    && ! in_array($class->name, $class->discriminatorMap, true)
-                ) {
+                if (! in_array($class->name, $class->discriminatorMap, true)) {
                     throw MappingException::mappedClassNotPartOfDiscriminatorMap($class->name, $class->rootEntityName);
                 }
             }

lib/Doctrine/ORM/Mapping/MappingException.php

@@ -762,8 +762,8 @@ public static function mappedClassNotPartOfDiscriminatorMap($className, $rootCla
     {
         return new self(
             "Entity '" . $className . "' has to be part of the discriminator map of '" . $rootClassName . "' " .
-            "to be properly mapped in the inheritance hierarchy. Alternatively you can make '" . $className . "' an abstract class " .
-            'to avoid this exception from occurring.'
+            'to be properly mapped in the inheritance hierarchy. The discriminator map needs to contain all ' .
+            'entity classes from the hierarchy, including abstract ones.'
         );
     }
 

tests/Doctrine/Tests/ORM/Mapping/BasicInheritanceMappingTest.php

@@ -131,19 +131,48 @@ public function testUnmappedSuperclassInHierarchy(): void
     }
 
     /** @group DDC-1204 */
-    public function testUnmappedEntityInHierarchy(): void
+    public function testNonAbstractEntityNotInDiscriminatorMap(): void
     {
+        // HierarchyE is in the DM, but the (non-abstract) parent class HierarchyBEntity is not
         $this->expectException(MappingException::class);
         $this->expectExceptionMessage(
             'Entity \'Doctrine\Tests\ORM\Mapping\HierarchyBEntity\' has to be part of the discriminator map'
             . ' of \'Doctrine\Tests\ORM\Mapping\HierarchyBase\' to be properly mapped in the inheritance hierarchy.'
-            . ' Alternatively you can make \'Doctrine\Tests\ORM\Mapping\HierarchyBEntity\' an abstract class to'
-            . ' avoid this exception from occurring.'
+            . ' The discriminator map needs to contain all entity classes from the hierarchy, including abstract ones.'
         );
 
         $this->cmf->getMetadataFor(HierarchyE::class);
     }
 
+    public function testAbstractEntityNotInDiscriminatorMap(): void
+    {
+        // Like testNonAbstractEntityNotInDiscriminatorMap(), but this time the parent class
+        // HierarchyF is abstract (and not in the DM as well)
+        $this->expectException(MappingException::class);
+        $this->expectExceptionMessage(
+            'Entity \'Doctrine\Tests\ORM\Mapping\HierarchyF\' has to be part of the discriminator map'
+            . ' of \'Doctrine\Tests\ORM\Mapping\HierarchyBase\' to be properly mapped in the inheritance hierarchy.'
+            . ' The discriminator map needs to contain all entity classes from the hierarchy, including abstract ones.'
+        );
+
+        $this->cmf->getMetadataFor(HierarchyG::class);
+    }
+
+    public function testAbstractRootEntityNotInDiscriminatorMap(): void
+    {
+        // Inheritance root entities go through a different path during runtime validation, so
+        // we need to check root classes separately. Even when the root class is abstract, it may
+        // not be omitted from the DM.
+        $this->expectException(MappingException::class);
+        $this->expectExceptionMessage(
+            'Entity \'Doctrine\Tests\ORM\Mapping\AbstractRootClass\' has to be part of the discriminator map'
+            . ' of \'Doctrine\Tests\ORM\Mapping\AbstractRootClass\' to be properly mapped in the inheritance hierarchy.'
+            . ' The discriminator map needs to contain all entity classes from the hierarchy, including abstract ones.'
+        );
+
+        $this->cmf->getMetadataFor(AbstractRootClass::class);
+    }
+
     /**
      * @group DDC-1204
      * @group DDC-1203
@@ -339,9 +368,11 @@ class EntityIndexSubClass extends MappedSuperclassBaseIndex
  * @InheritanceType("SINGLE_TABLE")
  * @DiscriminatorColumn(name="type", type="string", length=20)
  * @DiscriminatorMap({
+ *     "base"   = "HierarchyBase",
  *     "c"   = "HierarchyC",
  *     "d"   = "HierarchyD",
- *     "e"   = "HierarchyE"
+ *     "e"   = "HierarchyE",
+ *     "g"   = "HierarchyG"
  * })
  */
 abstract class HierarchyBase
@@ -406,6 +437,51 @@ class HierarchyE extends HierarchyBEntity
     public $e;
 }
 
+/** @Entity */
+abstract class HierarchyF extends HierarchyBase
+{
+    /**
+     * @var string
+     * @Column(type="string", length=255)
+     */
+    public $f;
+}
+
+/** @Entity */
+class HierarchyG extends HierarchyF
+{
+    /**
+     * @var string
+     * @Column(type="string", length=255)
+     */
+    public $e;
+}
+
+/**
+ * @Entity
+ * @InheritanceType("SINGLE_TABLE")
+ * @DiscriminatorColumn(name="type", type="string", length=20)
+ * @DiscriminatorMap({
+ *     "child"   = "AbstractRootClassChild"
+ * })
+ */
+abstract class AbstractRootClass
+{
+    /**
+     * @Column(type="integer")
+     * @Id
+     * @GeneratedValue
+     *
+     * @var int
+     */
+    public $id;
+}
+
+/** @Entity */
+class AbstractRootClassChild extends AbstractRootClass
+{
+}
+
 /** @Entity */
 class SuperclassEntity extends SuperclassBase
 {