From 3e2d9459aaf06b0e837666dda1cef8922f26b944 Mon Sep 17 00:00:00 2001
From: vladar <vladimir.razuvaev@gmail.com>
Date: Tue, 18 Oct 2016 22:23:20 +0700
Subject: [PATCH] resolveType for interface/unions is now allowed to return
 type name vs instance

---
 src/Executor/Executor.php       |  5 ++
 tests/Executor/AbstractTest.php | 81 ++++++++++++++++++++++++++++++++-
 2 files changed, 84 insertions(+), 2 deletions(-)

diff --git a/src/Executor/Executor.php b/src/Executor/Executor.php
index 3a46f5e..91271e1 100644
--- a/src/Executor/Executor.php
+++ b/src/Executor/Executor.php
@@ -734,6 +734,11 @@ class Executor
             call_user_func($resolveType, $result, $exeContext->contextValue, $info) :
             Type::getTypeOf($result, $exeContext->contextValue, $info, $returnType);
 
+        // If resolveType returns a string, we assume it's a ObjectType name.
+        if (is_string($runtimeType)) {
+            $runtimeType = $exeContext->schema->getType($runtimeType);
+        }
+
         if (!($runtimeType instanceof ObjectType)) {
             throw new Error(
                 "Abstract type {$returnType} must resolve to an Object type at runtime " .
diff --git a/tests/Executor/AbstractTest.php b/tests/Executor/AbstractTest.php
index f5f87c2..ea6687c 100644
--- a/tests/Executor/AbstractTest.php
+++ b/tests/Executor/AbstractTest.php
@@ -1,6 +1,8 @@
 <?php
 namespace GraphQL\Tests\Executor;
 
+require_once __DIR__ . '/TestClasses.php';
+
 use GraphQL\Executor\ExecutionResult;
 use GraphQL\Executor\Executor;
 use GraphQL\FormattedError;
@@ -13,8 +15,6 @@ use GraphQL\Type\Definition\ObjectType;
 use GraphQL\Type\Definition\Type;
 use GraphQL\Type\Definition\UnionType;
 
-spl_autoload_call('GraphQL\Tests\Executor\TestClasses');
-
 class AbstractTest extends \PHPUnit_Framework_TestCase
 {
     // Execute: Handles execution of abstract types
@@ -358,4 +358,81 @@ class AbstractTest extends \PHPUnit_Framework_TestCase
         ];
         $this->assertEquals($expected, $result);
     }
+
+    /**
+     * @it resolveType allows resolving with type name
+     */
+    public function testResolveTypeAllowsResolvingWithTypeName()
+    {
+        $PetType = new InterfaceType([
+            'name' => 'Pet',
+            'resolveType' => function($obj) {
+                if ($obj instanceof Dog) return 'Dog';
+                if ($obj instanceof Cat) return 'Cat';
+                return null;
+            },
+            'fields' => [
+                'name' => [ 'type' => Type::string() ]
+            ]
+        ]);
+
+        $DogType = new ObjectType([
+            'name' => 'Dog',
+            'interfaces' => [ $PetType ],
+            'fields' => [
+                'name' => [ 'type' => Type::string() ],
+                'woofs' => [ 'type' => Type::boolean() ],
+            ]
+        ]);
+
+        $CatType = new ObjectType([
+            'name' => 'Cat',
+            'interfaces' => [ $PetType ],
+            'fields' => [
+                'name' => [ 'type' => Type::string() ],
+                'meows' => [ 'type' => Type::boolean() ],
+            ]
+        ]);
+
+        $schema = new Schema([
+            'query' => new ObjectType([
+                'name' => 'Query',
+                'fields' => [
+                    'pets' => [
+                        'type' => Type::listOf($PetType),
+                        'resolve' => function() {
+                            return [
+                                new Dog('Odie', true),
+                                new Cat('Garfield', false)
+                            ];
+                        }
+                    ]
+                ]
+            ]),
+            'types' => [ $CatType, $DogType ]
+        ]);
+
+        $query = '{
+          pets {
+            name
+            ... on Dog {
+              woofs
+            }
+            ... on Cat {
+              meows
+            }
+          }
+        }';
+
+        $result = GraphQL::execute($schema, $query);
+
+        $this->assertEquals([
+            'data' => [
+                'pets' => [
+                    ['name' => 'Odie', 'woofs' => true],
+                    ['name' => 'Garfield', 'meows' => false]
+                ]
+            ]
+        ], $result);
+    }
 }