Allow enum discriminator columns

This commit adds enumType option to DiscriminatorColumn as well as support for custom DBAL types which use PHP enums for PHP values.
Previously, the enumType option was completely missing, but also even using custom types that used PHP enums would end up in exception because ObjectHydrator would try to convert enums to string using (string) explicit conversion.

Author: michnovka

docs/en/reference/attributes-reference.rst

@@ -366,6 +366,7 @@ Optional parameters:
 
 -  **type**: By default this is string.
 -  **length**: By default this is 255.
+-  **enumType**: By default this is `null`. Allows to map discriminatorColumn value to PHP enum
 
 .. _attrref_discriminatormap:
 

doctrine-mapping.xsd

@@ -337,6 +337,7 @@
     <xs:attribute name="field-name" type="xs:NMTOKEN" />
     <xs:attribute name="length" type="xs:NMTOKEN" />
     <xs:attribute name="column-definition" type="xs:string" />
+    <xs:attribute name="enum-type" type="xs:string" />
     <xs:anyAttribute namespace="##other"/>
   </xs:complexType>
 

lib/Doctrine/ORM/Internal/Hydration/AbstractHydrator.php

@@ -617,6 +617,7 @@ protected function hydrateColumnInfo($key)
                     'fieldName'    => $fieldName,
                     'type'         => $type,
                     'dqlAlias'     => $dqlAlias,
+                    'enumType'     => $this->_rsm->enumMappings[$key] ?? null,
                 ];
         }
 

lib/Doctrine/ORM/Internal/Hydration/ObjectHydrator.php

@@ -4,6 +4,7 @@
 
 namespace Doctrine\ORM\Internal\Hydration;
 
+use BackedEnum;
 use Doctrine\Common\Collections\ArrayCollection;
 use Doctrine\ORM\Mapping\ClassMetadata;
 use Doctrine\ORM\PersistentCollection;
@@ -246,7 +247,12 @@ private function getEntity(array $data, string $dqlAlias)
             }
 
             $discrMap           = $this->_metadataCache[$className]->discriminatorMap;
-            $discriminatorValue = (string) $data[$discrColumn];
+            $discriminatorValue = $data[$discrColumn];
+            if ($discriminatorValue instanceof BackedEnum) {
+                $discriminatorValue = $discriminatorValue->value;
+            }
+
+            $discriminatorValue = (string) $discriminatorValue;
 
             if (! isset($discrMap[$discriminatorValue])) {
                 throw HydrationException::invalidDiscriminatorValue($discriminatorValue, array_keys($discrMap));

lib/Doctrine/ORM/Mapping/ClassMetadataInfo.php

@@ -574,7 +574,7 @@ class ClassMetadataInfo implements ClassMetadata
      * READ-ONLY: The definition of the discriminator column used in JOINED and SINGLE_TABLE
      * inheritance mappings.
      *
-     * @psalm-var array{name: string, fieldName: string, type: string, length?: int, columnDefinition?: string|null}|null
+     * @psalm-var array{name: string, fieldName: string, type: string, length?: int, columnDefinition?: string|null, enumType?: class-string<BackedEnum>|null}|null
      */
     public $discriminatorColumn;
 
@@ -3220,7 +3220,7 @@ public function addEntityListener($eventName, $class, $method)
      * @see getDiscriminatorColumn()
      *
      * @param mixed[]|null $columnDef
-     * @psalm-param array{name: string|null, fieldName?: string, type?: string, length?: int, columnDefinition?: string|null}|null $columnDef
+     * @psalm-param array{name: string|null, fieldName?: string, type?: string, length?: int, columnDefinition?: string|null, enumType?: class-string<BackedEnum>|null}|null $columnDef
      *
      * @return void
      *

lib/Doctrine/ORM/Mapping/DiscriminatorColumn.php

@@ -39,15 +39,24 @@ final class DiscriminatorColumn implements MappingAttribute
      */
     public $columnDefinition;
 
+    /**
+     * @var class-string<\BackedEnum>|null
+     * @readonly
+     */
+    public $enumType = null;
+
+    /** @param class-string<\BackedEnum>|null $enumType */
     public function __construct(
         ?string $name = null,
         ?string $type = null,
         ?int $length = null,
-        ?string $columnDefinition = null
+        ?string $columnDefinition = null,
+        ?string $enumType = null
     ) {
         $this->name             = $name;
         $this->type             = $type;
         $this->length           = $length;
         $this->columnDefinition = $columnDefinition;
+        $this->enumType         = $enumType;
     }
 }

lib/Doctrine/ORM/Mapping/Driver/AnnotationDriver.php

@@ -319,6 +319,7 @@ public function loadMetadataForClass($className, PersistenceClassMetadata $metad
                             'type'             => $discrColumnAnnot->type ?: 'string',
                             'length'           => $discrColumnAnnot->length ?? 255,
                             'columnDefinition' => $discrColumnAnnot->columnDefinition,
+                            'enumType'         => $discrColumnAnnot->enumType,
                         ]
                     );
                 } else {

lib/Doctrine/ORM/Mapping/Driver/AttributeDriver.php

@@ -271,6 +271,7 @@ public function loadMetadataForClass($className, PersistenceClassMetadata $metad
                             'type'             => isset($discrColumnAttribute->type) ? (string) $discrColumnAttribute->type : 'string',
                             'length'           => isset($discrColumnAttribute->length) ? (int) $discrColumnAttribute->length : 255,
                             'columnDefinition' => isset($discrColumnAttribute->columnDefinition) ? (string) $discrColumnAttribute->columnDefinition : null,
+                            'enumType'         => isset($discrColumnAttribute->enumType) ? (string) $discrColumnAttribute->enumType : null,
                         ]
                     );
                 } else {

lib/Doctrine/ORM/Mapping/Driver/XmlDriver.php

@@ -210,6 +210,7 @@ public function loadMetadataForClass($className, PersistenceClassMetadata $metad
                             'type' => isset($discrColumn['type']) ? (string) $discrColumn['type'] : 'string',
                             'length' => isset($discrColumn['length']) ? (int) $discrColumn['length'] : 255,
                             'columnDefinition' => isset($discrColumn['column-definition']) ? (string) $discrColumn['column-definition'] : null,
+                            'enumType' => isset($discrColumn['enum-type']) ? (string) $discrColumn['enum-type'] : null,
                         ]
                     );
                 } else {

lib/Doctrine/ORM/Mapping/Driver/YamlDriver.php

@@ -201,6 +201,7 @@ public function loadMetadataForClass($className, PersistenceClassMetadata $metad
                             'type' => isset($discrColumn['type']) ? (string) $discrColumn['type'] : 'string',
                             'length' => isset($discrColumn['length']) ? (int) $discrColumn['length'] : 255,
                             'columnDefinition' => isset($discrColumn['columnDefinition']) ? (string) $discrColumn['columnDefinition'] : null,
+                            'enumType' => isset($discrColumn['enumType']) ? (string) $discrColumn['enumType'] : null,
                         ]
                     );
                 } else {

lib/Doctrine/ORM/Query/SqlWalker.php

@@ -775,6 +775,9 @@ public function walkSelectClause($selectClause)
 
                 $this->rsm->setDiscriminatorColumn($dqlAlias, $columnAlias);
                 $this->rsm->addMetaResult($dqlAlias, $columnAlias, $discrColumn['fieldName'], false, $discrColumn['type']);
+                if (! empty($discrColumn['enumType'])) {
+                    $this->rsm->addEnumResult($columnAlias, $discrColumn['enumType']);
+                }
             }
 
             // Add foreign key columns to SQL, if necessary

psalm-baseline.xml

@@ -785,7 +785,7 @@
     </UndefinedInterfaceMethod>
   </file>
   <file src="lib/Doctrine/ORM/Mapping/Driver/AttributeDriver.php">
-    <InvalidArgument occurrences="1"/>
+    <InvalidArgument occurrences="2"/>
     <InvalidArrayAccess occurrences="4">
       <code>$value[0]</code>
       <code>$value[0]</code>
@@ -865,7 +865,7 @@
       <code>addNamedNativeQuery</code>
       <code>addNamedQuery</code>
     </DeprecatedMethod>
-    <InvalidArgument occurrences="4">
+    <InvalidArgument occurrences="5">
       <code>$this-&gt;cacheToArray($manyToManyElement-&gt;cache)</code>
       <code>$this-&gt;cacheToArray($manyToOneElement-&gt;cache)</code>
       <code>$this-&gt;cacheToArray($oneToManyElement-&gt;cache)</code>
@@ -931,6 +931,7 @@
       <code>addNamedNativeQuery</code>
       <code>addNamedQuery</code>
     </DeprecatedMethod>
+    <InvalidArgument occurrences="1"/>
     <InvalidDocblock occurrences="1">
       <code>private function cacheToArray(array $cacheMapping): array</code>
     </InvalidDocblock>

tests/Doctrine/Tests/Models/GH10288/GH10288People.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\Tests\Models\GH10288;
+
+enum GH10288People: string
+{
+    case BOSS     = 'boss';
+    case EMPLOYEE = 'employee';
+}