Support native union return typing

src/Mappers/Parameters/TypeHandler.php

@@ -27,6 +27,7 @@
 use ReflectionParameter;
 use ReflectionProperty;
 use ReflectionType;
+use ReflectionUnionType;
 use TheCodingMachine\GraphQLite\Annotations\HideParameter;
 use TheCodingMachine\GraphQLite\Annotations\ParameterAnnotations;
 use TheCodingMachine\GraphQLite\Annotations\UseInputType;
@@ -42,6 +43,7 @@
 use TheCodingMachine\GraphQLite\Types\TypeResolver;
 use Webmozart\Assert\Assert;
 
+use function array_map;
 use function array_merge;
 use function array_unique;
 use function assert;
@@ -408,17 +410,36 @@ private function appendTypes(Type $type, ?Type $docBlockType): Type
  */
  private function reflectionTypeToPhpDocType(ReflectionType $type, ReflectionClass $reflectionClass): Type
  {
- assert($type instanceof ReflectionNamedType);
- $phpdocType = $this->phpDocumentorTypeResolver->resolve($type->getName());
- Assert::notNull($phpdocType);
+ assert($type instanceof ReflectionNamedType || $type instanceof ReflectionUnionType);
+ if ($type instanceof ReflectionNamedType) {
+ $phpdocType = $this->phpDocumentorTypeResolver->resolve($type->getName());
+ Assert::notNull($phpdocType);
 
- $phpdocType = $this->resolveSelf($phpdocType, $reflectionClass);
+  $phpdocType = $this->resolveSelf($phpdocType, $reflectionClass);
 
- if ($type->allowsNull()) {
- $phpdocType = new Nullable($phpdocType);
- }
+  if ($type->allowsNull()) {
+  $phpdocType = new Nullable($phpdocType);
+  }
 
- return $phpdocType;
+ return $phpdocType;
+ }
+ return new Compound(
+ array_map(
+ function ($namedType) use ($reflectionClass): Type {
+ \assert($namedType instanceof ReflectionNamedType);
+ $phpdocType = $this->phpDocumentorTypeResolver->resolve($namedType->getName());
+ Assert::notNull($phpdocType);
+
+ $phpdocType = $this->resolveSelf($phpdocType, $reflectionClass);
+
+ if ($namedType->allowsNull()) {
+ $phpdocType = new Nullable($phpdocType);
+ }
+ return $phpdocType;
+ },
+ $type->getTypes()
+ )
+ );
  }
 
  /**

tests/Fixtures80/UnionOutputType.php

@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace TheCodingMachine\GraphQLite\Fixtures80;
+
+use TheCodingMachine\GraphQLite\Fixtures\TestObject;
+use TheCodingMachine\GraphQLite\Fixtures\TestObject2;
+
+class UnionOutputType
+{
+ public function objectUnion(): TestObject|TestObject2 {
+ return new TestObject((''));
+ }
+}

tests/Mappers/Parameters/TypeMapperTest.php

@@ -3,13 +3,16 @@
 namespace TheCodingMachine\GraphQLite\Mappers\Parameters;
 
 use DateTimeImmutable;
+use GraphQL\Type\Definition\NonNull;
 use GraphQL\Type\Definition\ResolveInfo;
+use GraphQL\Type\Definition\UnionType;
 use ReflectionMethod;
 use Symfony\Component\Cache\Adapter\ArrayAdapter;
 use Symfony\Component\Cache\Psr16Cache;
 use Symfony\Component\Cache\Simple\ArrayCache;
 use TheCodingMachine\GraphQLite\AbstractQueryProviderTest;
 use TheCodingMachine\GraphQLite\Annotations\HideParameter;
+use TheCodingMachine\GraphQLite\Fixtures80\UnionOutputType;
 use TheCodingMachine\GraphQLite\Mappers\CannotMapTypeException;
 use TheCodingMachine\GraphQLite\Mappers\Root\BaseTypeMapper;
 use TheCodingMachine\GraphQLite\Mappers\Root\CompositeRootTypeMapper;
@@ -34,6 +37,29 @@ public function testMapScalarUnionException(): void
  $typeMapper->mapReturnType($refMethod, $docBlockObj);
  }
 
+ /**
+ * @requires PHP >= 8.0
+ */
+ public function testMapObjectUnionWorks(): void
+ {
+ $typeMapper = new TypeHandler($this->getArgumentResolver(), $this->getRootTypeMapper(), $this->getTypeResolver());
+
+ $cachedDocBlockFactory = new CachedDocBlockFactory(new Psr16Cache(new ArrayAdapter()));
+
+ $refMethod = new ReflectionMethod(UnionOutputType::class, 'objectUnion');
+ $docBlockObj = $cachedDocBlockFactory->getDocBlock($refMethod);
+
+ $gqType = $typeMapper->mapReturnType($refMethod, $docBlockObj);
+ $this->assertInstanceOf(NonNull::class, $gqType);
+ assert($gqType instanceof NonNull);
+ $memberType = $gqType->getOfType();
+ $this->assertInstanceOf(UnionType::class, $memberType);
+ assert($memberType instanceof UnionType);
+ $unionTypes = $memberType->getTypes();
+ $this->assertEquals('TestObject', $unionTypes[0]->name);
+ $this->assertEquals('TestObject2', $unionTypes[1]->name);
+ }
+
  public function testHideParameter(): void
  {
  $typeMapper = new TypeHandler($this->getArgumentResolver(), $this->getRootTypeMapper(), $this->getTypeResolver());