Fixed null for union types (#500)

* unit test for union type with null

* Nullable union test

* Nullable union bug fix

* Fix test for old php version

Co-authored-by: madness <ss@gmail.com>

Author: l-you

src/Mappers/Root/CompoundTypeMapper.php

@@ -15,6 +15,8 @@
 use phpDocumentor\Reflection\Type;
 use phpDocumentor\Reflection\Types\Compound;
 use phpDocumentor\Reflection\Types\Iterable_;
+use phpDocumentor\Reflection\Types\Null_;
+use phpDocumentor\Reflection\Types\Nullable;
 use ReflectionMethod;
 use ReflectionProperty;
 use RuntimeException;
@@ -76,6 +78,9 @@ public function toGraphQLOutputType(Type $type, ?OutputType $subType, $reflector
                 $mustBeIterable = true;
                 continue;
             }
+            if ($singleDocBlockType instanceof Nullable && $singleDocBlockType->getActualType() instanceof Null_) {
+                continue;
+            }
             $unionTypes[] = $this->topRootTypeMapper->toGraphQLOutputType($singleDocBlockType, null, $reflector, $docBlockObj);
         }
 

tests/Fixtures80/UnionOutputType.php

@@ -12,4 +12,7 @@ class UnionOutputType
     public function objectUnion(): TestObject|TestObject2 {
         return new TestObject((''));
     }
+    public function nullableObjectUnion(): TestObject|TestObject2|null {
+        return new TestObject((''));
+    }
 }

tests/Mappers/Parameters/TypeMapperTest.php

@@ -59,6 +59,29 @@ public function testMapObjectUnionWorks(): void
         $this->assertEquals('TestObject', $unionTypes[0]->name);
         $this->assertEquals('TestObject2', $unionTypes[1]->name);
     }
+    /**
+     * @requires PHP >= 8.0
+     */
+    public function testMapObjectNullableUnionWorks(): void
+    {
+        $typeMapper = new TypeHandler($this->getArgumentResolver(), $this->getRootTypeMapper(), $this->getTypeResolver());
+
+        $cachedDocBlockFactory = new CachedDocBlockFactory(new Psr16Cache(new ArrayAdapter()));
+
+        $refMethod = new ReflectionMethod(UnionOutputType::class, 'nullableObjectUnion');
+        $docBlockObj = $cachedDocBlockFactory->getDocBlock($refMethod);
+
+        $gqType = $typeMapper->mapReturnType($refMethod, $docBlockObj);
+        $this->assertNotInstanceOf(NonNull::class, $gqType);
+        assert(!($gqType instanceof NonNull));
+        $this->assertInstanceOf(UnionType::class, $gqType);
+        assert($gqType instanceof UnionType);
+        $unionTypes = $gqType->getTypes();
+        $this->assertEquals(2, count($unionTypes));
+        $this->assertEquals('TestObject', $unionTypes[0]->name);
+        $this->assertEquals('TestObject2', $unionTypes[1]->name);
+
+    }
 
     public function testHideParameter(): void
     {
@@ -99,21 +122,24 @@ public function testHideParameterException(): void
     /**
      * @return int|string
      */
-    private function dummy() {
+    private function dummy()
+    {
 
     }
 
     /**
      * @HideParameter(for="$foo")
      */
-    private function withDefaultValue($foo = 24) {
+    private function withDefaultValue($foo = 24)
+    {
 
     }
 
     /**
      * @HideParameter(for="$foo")
      */
-    private function withoutDefaultValue($foo) {
+    private function withoutDefaultValue($foo)
+    {
 
     }
 }