Add support for inherited nullability from PHP

docs/en/reference/advanced-configuration.rst

@@ -184,6 +184,24 @@ For development you should use an array cache like
 ``Symfony\Component\Cache\Adapter\ArrayAdapter``
 which only caches data on a per-request basis.
 
+Nullability detection (***RECOMMENDED***)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. note::
+
+    Since ORM 3.4.0
+
+.. code-block:: php
+
+    <?php
+    $config->setInferPhpNullability(true);
+
+Sets whether Doctrine should infer the nullability of PHP types to the
+database schema. This is useful when using PHP 7.4+ typed properties
+
+You can always override the inferred nullability by specifying the
+``nullable`` option in the Column or JoinColumn definition.
+
 SQL Logger (***Optional***)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/en/reference/attributes-reference.rst

@@ -176,7 +176,8 @@ Optional parameters:
    should be unique across all rows of the underlying entities table.
 
 -  **nullable**: Determines if NULL values allowed for this column.
-    If not specified, default value is ``false``.
+    If not specified, default value is ``false``. 
+    Since ORM 3.4, default can be inferred from PHP type when using ``$config->setInferPhpNullability(true)``.
 
 -  **insertable**: Boolean value to determine if the column should be
    included when inserting a new row into the underlying entities table.
@@ -674,6 +675,7 @@ Optional parameters:
    constraint level. Defaults to false.
 -  **nullable**: Determine whether the related entity is required, or if
    null is an allowed state for the relation. Defaults to true.
+   Since ORM 3.4, default can be inferred from PHP type when using ``$config->setInferPhpNullability(true)``.
 -  **onDelete**: Cascade Action (Database-level)
 -  **columnDefinition**: DDL SQL snippet that starts after the column
    name and specifies the complete (non-portable!) column definition.

docs/en/reference/xml-mapping.rst

@@ -256,7 +256,7 @@ Optional attributes:
 -  unique - Should this field contain a unique value across the
    table? Defaults to false.
 -  nullable - Should this field allow NULL as a value? Defaults to
-   false.
+   false. Since ORM 3.4, default can be inferred from PHP type when using ``$config->setInferPhpNullability(true)``.
 -  insertable - Should this field be inserted? Defaults to true.
 -  updatable - Should this field be updated? Defaults to true.
 -  generated - Enum of the values ALWAYS, INSERT, NEVER that determines if
@@ -717,6 +717,7 @@ Optional attributes:
    This makes sense for Many-To-Many join-columns only to simulate a
    one-to-many unidirectional using a join-table.
 -  nullable - should the join column be nullable, defaults to true.
+   Since ORM 3.4, default can be inferred from PHP type when using ``$config->setInferPhpNullability(true)``.
 -  on-delete - Foreign Key Cascade action to perform when entity is
    deleted, defaults to NO ACTION/RESTRICT but can be set to
    "CASCADE".

phpstan-baseline.neon

@@ -991,7 +991,7 @@ parameters:
 			path: src/Mapping/ClassMetadata.php
 
 		-
-			message: '#^Parameter \#1 \$mapping of method Doctrine\\ORM\\Mapping\\ClassMetadata\<T of object\>\:\:validateAndCompleteTypedAssociationMapping\(\) expects array\{type\: 1\|2\|4\|8, fieldName\: string, targetEntity\?\: class\-string\}, non\-empty\-array\<string, mixed\> given\.$#'
+			message: '#^Parameter \#1 \$mapping of method Doctrine\\ORM\\Mapping\\ClassMetadata\<T of object\>\:\:validateAndCompleteTypedAssociationMapping\(\) expects array\{type\: 1\|2\|4\|8, fieldName\: string, targetEntity\?\: class\-string, joinColumns\: array\<int, array\<string, mixed\>\>\|null\}, non\-empty\-array\<string, mixed\> given\.$#'
 			identifier: argument.type
 			count: 1
 			path: src/Mapping/ClassMetadata.php

src/Configuration.php

@@ -644,4 +644,14 @@ public function getEagerFetchBatchSize(): int
     {
         return $this->attributes['fetchModeSubselectBatchSize'] ?? 100;
     }
+
+    public function setInferPhpNullability(bool $inferPhpNullability): void
+    {
+        $this->attributes['inferPhpNullability'] = $inferPhpNullability;
+    }
+
+    public function isPhpNullabilityInferred(): bool
+    {
+        return $this->attributes['inferPhpNullability'] ?? false;
+    }
 }

src/Mapping/ClassMetadata.php

@@ -22,6 +22,7 @@
 use ReflectionClass;
 use ReflectionNamedType;
 use ReflectionProperty;
+use ReflectionType;
 use Stringable;
 
 use function array_column;
@@ -556,7 +557,7 @@ class ClassMetadata implements PersistenceClassMetadata, Stringable
      * @param string $name The name of the entity class the new instance is used for.
      * @phpstan-param class-string<T> $name
      */
-    public function __construct(public string $name, NamingStrategy|null $namingStrategy = null, TypedFieldMapper|null $typedFieldMapper = null)
+    public function __construct(public string $name, NamingStrategy|null $namingStrategy = null, TypedFieldMapper|null $typedFieldMapper = null, public readonly bool $inferPhpNullability = false)
     {
         $this->rootEntityName   = $name;
         $this->namingStrategy   = $namingStrategy ?? new DefaultNamingStrategy();
@@ -1124,14 +1125,12 @@ private function validateAndCompleteTypedFieldMapping(array $mapping): array
     /**
      * Validates & completes the basic mapping information based on typed property.
      *
-     * @param array{type: self::ONE_TO_ONE|self::MANY_TO_ONE|self::ONE_TO_MANY|self::MANY_TO_MANY, fieldName: string, targetEntity?: class-string} $mapping The mapping.
+     * @param array{type: self::ONE_TO_ONE|self::MANY_TO_ONE|self::ONE_TO_MANY|self::MANY_TO_MANY, fieldName: string, targetEntity?: class-string, joinColumns: array<int, array<string, mixed>>|null} $mapping The mapping.
      *
      * @return mixed[] The updated mapping.
      */
-    private function validateAndCompleteTypedAssociationMapping(array $mapping): array
+    private function validateAndCompleteTypedAssociationMapping(array $mapping, ReflectionType|null $type): array
     {
-        $type = $this->reflClass->getProperty($mapping['fieldName'])->getType();
-
         if ($type === null || ($mapping['type'] & self::TO_ONE) === 0) {
             return $mapping;
         }
@@ -1152,6 +1151,7 @@ private function validateAndCompleteTypedAssociationMapping(array $mapping): arr
      *     id?: bool,
      *     generated?: self::GENERATED_*,
      *     enumType?: class-string,
+     *     nullable?: bool|null,
      * } $mapping The field mapping to validate & complete.
      *
      * @return FieldMapping The updated mapping.
@@ -1165,10 +1165,17 @@ protected function validateAndCompleteFieldMapping(array $mapping): FieldMapping
             throw MappingException::missingFieldName($this->name);
         }
 
+        $type = null;
         if ($this->isTypedProperty($mapping['fieldName'])) {
+            $type    = $this->reflClass->getProperty($mapping['fieldName'])->getType();
             $mapping = $this->validateAndCompleteTypedFieldMapping($mapping);
         }
 
+        // Infer nullable from type or reset null back to true if type is missing
+        if ($this->inferPhpNullability && ! isset($mapping['nullable'])) {
+            $mapping['nullable'] = $type?->allowsNull() ?? false;
+        }
+
         if (! isset($mapping['type'])) {
             // Default to string
             $mapping['type'] = 'string';
@@ -1276,8 +1283,29 @@ protected function _validateAndCompleteAssociationMapping(array $mapping): Assoc
         // the sourceEntity.
         $mapping['sourceEntity'] = $this->name;
 
+        $type = null;
         if ($this->isTypedProperty($mapping['fieldName'])) {
-            $mapping = $this->validateAndCompleteTypedAssociationMapping($mapping);
+            $type    = $this->reflClass->getProperty($mapping['fieldName'])->getType();
+            $mapping = $this->validateAndCompleteTypedAssociationMapping($mapping, $type);
+        }
+
+        // Infer nullable from type or reset null back to true if type is missing
+        if ($this->inferPhpNullability && $mapping['type'] & self::TO_ONE) {
+            if (! empty($mapping['joinColumns'])) {
+                foreach ($mapping['joinColumns'] as $key => $data) {
+                    if (! isset($data['nullable'])) {
+                        $mapping['joinColumns'][$key]['nullable'] = $type?->allowsNull() ?? true;
+                    }
+                }
+            } elseif ($type !== null) {
+                $mapping['joinColumns'] = [
+                    [
+                        'fieldName' => $mapping['fieldName'],
+                        'nullable' => $type->allowsNull(),
+                        'referencedColumnName' => $this->namingStrategy->referenceColumnName(),
+                    ],
+                ];
+            }
         }
 
         if (isset($mapping['targetEntity'])) {

src/Mapping/ClassMetadataFactory.php

@@ -304,6 +304,7 @@ protected function newClassMetadataInstance(string $className): ClassMetadata
             $className,
             $this->em->getConfiguration()->getNamingStrategy(),
             $this->em->getConfiguration()->getTypedFieldMapper(),
+            $this->em->getConfiguration()->isPhpNullabilityInferred(),
         );
     }
 

src/Mapping/Column.php

@@ -10,6 +10,9 @@
 #[Attribute(Attribute::TARGET_PROPERTY)]
 final class Column implements MappingAttribute
 {
+    public readonly bool $nullable;
+    public readonly bool $nullableSet;
+
     /**
      * @param int|null                      $precision The precision for a decimal (exact numeric) column (Applies only for decimal column).
      * @param int|null                      $scale     The scale for a decimal (exact numeric) column (Applies only for decimal column).
@@ -24,13 +27,15 @@ public function __construct(
         public readonly int|null $precision = null,
         public readonly int|null $scale = null,
         public readonly bool $unique = false,
-        public readonly bool $nullable = false,
+        bool|null $nullable = null,
         public readonly bool $insertable = true,
         public readonly bool $updatable = true,
         public readonly string|null $enumType = null,
         public readonly array $options = [],
         public readonly string|null $columnDefinition = null,
         public readonly string|null $generated = null,
     ) {
+        $this->nullable    = $nullable ?? false;
+        $this->nullableSet = $nullable !== null;
     }
 }

src/Mapping/Driver/AttributeDriver.php

@@ -297,7 +297,7 @@ public function loadMetadataForClass(string $className, PersistenceClassMetadata
             $joinColumnAttributes = $this->reader->getPropertyAttributeCollection($property, Mapping\JoinColumn::class);
 
             foreach ($joinColumnAttributes as $joinColumnAttribute) {
-                $joinColumns[] = $this->joinColumnToArray($joinColumnAttribute);
+                $joinColumns[] = $this->joinColumnToArray($joinColumnAttribute, $metadata->inferPhpNullability);
             }
 
             // Field can only be attributed with one of:
@@ -310,7 +310,7 @@ public function loadMetadataForClass(string $className, PersistenceClassMetadata
             $embeddedAttribute   = $this->reader->getPropertyAttribute($property, Mapping\Embedded::class);
 
             if ($columnAttribute !== null) {
-                $mapping = $this->columnToArray($property->name, $columnAttribute);
+                $mapping = $this->columnToArray($property->name, $columnAttribute, $metadata->inferPhpNullability);
 
                 if ($this->reader->getPropertyAttribute($property, Mapping\Id::class)) {
                     $mapping['id'] = true;
@@ -530,7 +530,7 @@ public function loadMetadataForClass(string $className, PersistenceClassMetadata
             $attributeOverridesAnnot = $classAttributes[Mapping\AttributeOverrides::class];
 
             foreach ($attributeOverridesAnnot->overrides as $attributeOverride) {
-                $mapping = $this->columnToArray($attributeOverride->name, $attributeOverride->column);
+                $mapping = $this->columnToArray($attributeOverride->name, $attributeOverride->column, $metadata->inferPhpNullability);
 
                 $metadata->setAttributeOverride($attributeOverride->name, $mapping);
             }
@@ -680,12 +680,12 @@ private function getMethodCallbacks(ReflectionMethod $method): array
      *                   options?: array<string, mixed>
      *               }
      */
-    private function joinColumnToArray(Mapping\JoinColumn|Mapping\InverseJoinColumn $joinColumn): array
+    private function joinColumnToArray(Mapping\JoinColumn|Mapping\InverseJoinColumn $joinColumn, bool $inferPhpNullability = false): array
     {
         $mapping = [
             'name' => $joinColumn->name,
             'unique' => $joinColumn->unique,
-            'nullable' => $joinColumn->nullable,
+            'nullable' => $inferPhpNullability && ! $joinColumn->nullableSet ? null : $joinColumn->nullable,
             'onDelete' => $joinColumn->onDelete,
             'columnDefinition' => $joinColumn->columnDefinition,
             'referencedColumnName' => $joinColumn->referencedColumnName,
@@ -708,23 +708,23 @@ private function joinColumnToArray(Mapping\JoinColumn|Mapping\InverseJoinColumn
      *                   scale: int,
      *                   length: int,
      *                   unique: bool,
-     *                   nullable: bool,
+     *                   nullable: bool|null,
      *                   precision: int,
      *                   enumType?: class-string,
      *                   options?: mixed[],
      *                   columnName?: string,
      *                   columnDefinition?: string
      *               }
      */
-    private function columnToArray(string $fieldName, Mapping\Column $column): array
+    private function columnToArray(string $fieldName, Mapping\Column $column, bool $inferPhpNullability = false): array
     {
         $mapping = [
             'fieldName' => $fieldName,
             'type'      => $column->type,
             'scale'     => $column->scale,
             'length'    => $column->length,
             'unique'    => $column->unique,
-            'nullable'  => $column->nullable,
+            'nullable'  => $inferPhpNullability && ! $column->nullableSet ? null : $column->nullable,
             'precision' => $column->precision,
         ];
 

src/Mapping/JoinColumnProperties.php

@@ -6,16 +6,21 @@
 
 trait JoinColumnProperties
 {
+    public readonly bool $nullable;
+    public readonly bool $nullableSet;
+
     /** @param array<string, mixed> $options */
     public function __construct(
         public readonly string|null $name = null,
         public readonly string|null $referencedColumnName = null,
         public readonly bool $unique = false,
-        public readonly bool $nullable = true,
+        bool|null $nullable = null,
         public readonly mixed $onDelete = null,
         public readonly string|null $columnDefinition = null,
         public readonly string|null $fieldName = null,
         public readonly array $options = [],
     ) {
+        $this->nullable    = $nullable ?? true;
+        $this->nullableSet = $nullable !== null;
     }
 }

src/ORMSetup.php

@@ -34,7 +34,7 @@ public static function createAttributeMetadataConfiguration(
         CacheItemPoolInterface|null $cache = null,
     ): Configuration {
         $config = self::createConfiguration($isDevMode, $proxyDir, $cache);
-        $config->setMetadataDriverImpl(new AttributeDriver($paths));
+        $config->setMetadataDriverImpl(new AttributeDriver($paths, true));
 
         return $config;
     }

tests/Tests/Models/TypedProperties/Contact.php

@@ -5,10 +5,16 @@
 namespace Doctrine\Tests\Models\TypedProperties;
 
 use Doctrine\ORM\Mapping as ORM;
+use Doctrine\ORM\Mapping\ClassMetadata;
 
 #[ORM\Embeddable]
 class Contact
 {
     #[ORM\Column]
     public string|null $email = null;
+
+    public static function loadMetadata(ClassMetadata $metadata): void
+    {
+        $metadata->mapField(['fieldName' => 'email', 'type' => 'string']);
+    }
 }