feature #31486 [Doctrine][PropertyInfo] Detect if the ID is writeable (dunglas)

This PR was merged into the 4.3 branch.

Discussion
----------

[Doctrine][PropertyInfo] Detect if the ID is writeable

| Q             | A
| ------------- | ---
| Branch?       | 4.3
| Bug fix?      | yes
| New feature?  | yes <!-- please update src/**/CHANGELOG.md files -->
| BC breaks?    | no     <!-- see https://symfony.com/bc -->
| Deprecations? | yes/no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tests pass?   | yes    <!-- please add some, will be required by reviewers -->
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

Companion of #31481. Allows to detect that ids with a generated value aren't writable (because the DBMS will generate the ID by itself). It could be considered as a bug fix or as a new feature. I prefer to not merge in in 3.4. However, it becomes necessary for autovalidation to work with such entities, so it should be in 4.3:

```php
/**
 * @Entity
 */
class Foo
{
    /**
     * @Id
     * @GeneratedValue(strategy="AUTO")
     * @Column(type="integer")
     */
    public $id;
}
```

Commits
-------

4598235192 [Doctrine][PropertyInfo] Detect if the ID is writeable

src/Symfony/Bridge/Doctrine/PropertyInfo/DoctrineExtractor.php

@@ -15,8 +15,10 @@ use Doctrine\Common\Persistence\Mapping\ClassMetadataFactory;
 use Doctrine\Common\Persistence\Mapping\MappingException;
 use Doctrine\DBAL\Types\Type as DBALType;
 use Doctrine\ORM\EntityManagerInterface;
+use Doctrine\ORM\Mapping\ClassMetadata;
 use Doctrine\ORM\Mapping\ClassMetadataInfo;
 use Doctrine\ORM\Mapping\MappingException as OrmMappingException;
+use Symfony\Component\PropertyInfo\PropertyAccessExtractorInterface;
 use Symfony\Component\PropertyInfo\PropertyListExtractorInterface;
 use Symfony\Component\PropertyInfo\PropertyTypeExtractorInterface;
 use Symfony\Component\PropertyInfo\Type;
@@ -26,7 +28,7 @@ use Symfony\Component\PropertyInfo\Type;
  *
  * @author Kévin Dunglas <dunglas@gmail.com>
  */
-class DoctrineExtractor implements PropertyListExtractorInterface, PropertyTypeExtractorInterface
+class DoctrineExtractor implements PropertyListExtractorInterface, PropertyTypeExtractorInterface, PropertyAccessExtractorInterface
 {
     private $entityManager;
     private $classMetadataFactory;
@@ -51,12 +53,8 @@ class DoctrineExtractor implements PropertyListExtractorInterface, PropertyTypeE
      */
     public function getProperties($class, array $context = [])
     {
-        try {
-            $metadata = $this->entityManager ? $this->entityManager->getClassMetadata($class) : $this->classMetadataFactory->getMetadataFor($class);
-        } catch (MappingException $exception) {
-            return;
-        } catch (OrmMappingException $exception) {
-            return;
+        if (null === $metadata = $this->getMetadata($class)) {
+            return null;
         }
 
         $properties = array_merge($metadata->getFieldNames(), $metadata->getAssociationNames());
@@ -77,12 +75,8 @@ class DoctrineExtractor implements PropertyListExtractorInterface, PropertyTypeE
      */
     public function getTypes($class, $property, array $context = [])
     {
-        try {
-            $metadata = $this->entityManager ? $this->entityManager->getClassMetadata($class) : $this->classMetadataFactory->getMetadataFor($class);
-        } catch (MappingException $exception) {
-            return;
-        } catch (OrmMappingException $exception) {
-            return;
+        if (null === $metadata = $this->getMetadata($class)) {
+            return null;
         }
 
         if ($metadata->hasAssociation($property)) {
@@ -176,6 +170,39 @@ class DoctrineExtractor implements PropertyListExtractorInterface, PropertyTypeE
         }
     }
 
+    /**
+     * {@inheritdoc}
+     */
+    public function isReadable($class, $property, array $context = [])
+    {
+        return null;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function isWritable($class, $property, array $context = [])
+    {
+        if (
+            null === ($metadata = $this->getMetadata($class))
+            || ClassMetadata::GENERATOR_TYPE_NONE === $metadata->generatorType
+            || !\in_array($property, $metadata->getIdentifierFieldNames(), true)
+        ) {
+            return null;
+        }
+
+        return false;
+    }
+
+    private function getMetadata(string $class): ?ClassMetadata
+    {
+        try {
+            return $this->entityManager ? $this->entityManager->getClassMetadata($class) : $this->classMetadataFactory->getMetadataFor($class);
+        } catch (MappingException | OrmMappingException $exception) {
+            return null;
+        }
+    }
+
     /**
      * Determines whether an association is nullable.
      *

src/Symfony/Bridge/Doctrine/Tests/PropertyInfo/DoctrineExtractorTest.php

@@ -16,6 +16,7 @@ use Doctrine\ORM\EntityManager;
 use Doctrine\ORM\Tools\Setup;
 use PHPUnit\Framework\TestCase;
 use Symfony\Bridge\Doctrine\PropertyInfo\DoctrineExtractor;
+use Symfony\Bridge\Doctrine\Tests\PropertyInfo\Fixtures\DoctrineGeneratedValue;
 use Symfony\Component\PropertyInfo\Type;
 
 /**
@@ -223,4 +224,13 @@ class DoctrineExtractorTest extends TestCase
     {
         $this->assertNull($this->createExtractor($legacy)->getTypes('Not\Exist', 'baz'));
     }
+
+    public function testGeneratedValueNotWritable()
+    {
+        $extractor = $this->createExtractor();
+        $this->assertFalse($extractor->isWritable(DoctrineGeneratedValue::class, 'id'));
+        $this->assertNull($extractor->isReadable(DoctrineGeneratedValue::class, 'id'));
+        $this->assertNull($extractor->isWritable(DoctrineGeneratedValue::class, 'foo'));
+        $this->assertNull($extractor->isReadable(DoctrineGeneratedValue::class, 'foo'));
+    }
 }

src/Symfony/Bridge/Doctrine/Tests/PropertyInfo/Fixtures/DoctrineGeneratedValue.php

@@ -0,0 +1,37 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Bridge\Doctrine\Tests\PropertyInfo\Fixtures;
+
+use Doctrine\ORM\Mapping\Column;
+use Doctrine\ORM\Mapping\Entity;
+use Doctrine\ORM\Mapping\GeneratedValue;
+use Doctrine\ORM\Mapping\Id;
+
+/**
+ * @author Kévin Dunglas <dunglas@gmail.com>
+ *
+ * @Entity
+ */
+class DoctrineGeneratedValue
+{
+    /**
+     * @Id
+     * @GeneratedValue(strategy="AUTO")
+     * @Column(type="integer")
+     */
+    public $id;
+
+    /**
+     * @Column
+     */
+    public $foo;
+}