[LiveComponent] Support for liveProp union type

src/LiveComponent/CHANGELOG.md

@@ -1,5 +1,10 @@
 # CHANGELOG
 
+## 2.32
+
+- Add support for `LiveProp` union types in Live Components.
+  `LiveComponentMetadataFactory` can now create `liveProp` metadata for union types.
+
 ## 2.31
 
 -  Add browser events assertions in `InteractsWithLiveComponents`:

src/LiveComponent/src/Metadata/LiveComponentMetadataFactory.php

@@ -83,12 +83,13 @@ public function createPropMetadatas(\ReflectionClass $class): array
     public function createLivePropMetadata(string $className, string $propertyName, \ReflectionProperty $property, LiveProp $liveProp): LivePropMetadata|LegacyLivePropMetadata
     {
         $reflectionType = $property->getType();
-        if ($reflectionType instanceof \ReflectionUnionType || $reflectionType instanceof \ReflectionIntersectionType) {
-            throw new \LogicException(\sprintf('Union or intersection types are not supported for LiveProps. You may want to change the type of property "%s" in "%s".', $property->getName(), $property->getDeclaringClass()->getName()));
-        }
 
         // BC layer when "symfony/type-info" is not available
         if (!method_exists($this->propertyTypeExtractor, 'getType')) {
+            if ($reflectionType instanceof \ReflectionUnionType || $reflectionType instanceof \ReflectionIntersectionType) {
+                return new LegacyLivePropMetadata($property->getName(), $liveProp, 'mixed', true, $reflectionType->allowsNull(), null);
+            }
+
             $infoTypes = $this->propertyTypeExtractor->getTypes($className, $propertyName) ?? [];
 
             $collectionValueType = null;
@@ -122,6 +123,10 @@ public function createLivePropMetadata(string $className, string $propertyName,
                 $collectionValueType
             );
         } else {
+            if ($reflectionType instanceof \ReflectionUnionType || $reflectionType instanceof \ReflectionIntersectionType) {
+                return new LivePropMetadata($property->getName(), $liveProp, Type::mixed());
+            }
+
             $infoType = $this->propertyTypeExtractor->getType($className, $property->getName());
 
             if ($infoType instanceof CollectionType) {

src/LiveComponent/tests/Fixtures/Component/WithUnionIntersectionType.php

@@ -0,0 +1,30 @@
+<?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\UX\LiveComponent\Tests\Fixtures\Component;
+
+use Symfony\UX\LiveComponent\Attribute\AsLiveComponent;
+use Symfony\UX\LiveComponent\Attribute\LiveProp;
+use Symfony\UX\LiveComponent\DefaultActionTrait;
+use Symfony\UX\LiveComponent\Tests\Fixtures\Enum\IntEnum;
+use Symfony\UX\LiveComponent\Tests\Fixtures\Enum\ZeroIntEnum;
+
+#[AsLiveComponent('with_union_intersection_type')]
+final class WithUnionIntersectionType
+{
+    use DefaultActionTrait;
+
+    #[LiveProp]
+    public int|float|null $unionProp = null;
+
+    #[LiveProp]
+    public IntEnum&ZeroIntEnum $intersectionProp;
+}

src/LiveComponent/tests/Functional/Metadata/LiveComponentMetadataFactoryTest.php

@@ -15,6 +15,7 @@
 use Symfony\UX\LiveComponent\Metadata\LiveComponentMetadataFactory;
 use Symfony\UX\LiveComponent\Metadata\UrlMapping;
 use Symfony\UX\LiveComponent\Tests\Fixtures\Component\ComponentWithUrlBoundProps;
+use Symfony\UX\LiveComponent\Tests\Fixtures\Component\WithUnionIntersectionType;
 
 class LiveComponentMetadataFactoryTest extends KernelTestCase
 {
@@ -42,4 +43,21 @@ public function testQueryStringMapping()
         $this->assertEquals(new UrlMapping(as: 'q'), $propsMetadataByName['boundPropWithAlias']->urlMapping());
         $this->assertNotNull($propsMetadataByName['boundPropWithCustomAlias']);
     }
+
+    public function testLivePropUnionType()
+    {
+        /** @var LiveComponentMetadataFactory $metadataFactory */
+        $metadataFactory = self::getContainer()->get('ux.live_component.metadata_factory');
+
+        $class = new \ReflectionClass(WithUnionIntersectionType::class);
+        $propsMetadata = $metadataFactory->createPropMetadatas($class);
+
+        $propsMetadataByName = [];
+        foreach ($propsMetadata as $propMetadata) {
+            $propsMetadataByName[$propMetadata->getName()] = $propMetadata;
+        }
+
+        $this->assertEquals('mixed', (string) $propsMetadataByName['unionProp']->getType());
+        $this->assertEquals('mixed', (string) $propsMetadataByName['intersectionProp']->getType());
+    }
 }

src/LiveComponent/tests/Integration/LiveComponentHydratorTest.php

@@ -1636,6 +1636,23 @@ public function testInterfaceTypedLivePropCannotBeDehydrated()
         $this->hydrator()->dehydrate($component, $this->createComponentAttributes(), $this->createLiveMetadata($component));
     }
 
+    public function testObjectTypedLivePropCannotBeDehydrated()
+    {
+        $componentClass = new class {
+            #[LiveProp(writable: true)]
+            public object $object;
+        };
+
+        $component = new $componentClass();
+        $component->object = new class {
+        };
+
+        $this->expectException(\LogicException::class);
+        $this->expectExceptionMessageMatches('/The "object" property on component ".*" is missing its property-type. Add the ".*" type so the object can be hydrated later./');
+
+        $this->hydrator()->dehydrate($component, $this->createComponentAttributes(), $this->createLiveMetadata($component));
+    }
+
     /**
      * @dataProvider provideInvalidHydrationTests
      */