Merge pull request #486 from mcg-web/fix-coroutine-when-using-promise

Fix coroutine executor when using with promise

src/Experimental/Executor/CoroutineExecutor.php

@@ -293,13 +293,17 @@ class CoroutineExecutor implements Runtime, ExecutorImplementation
                         $strand->stack[$strand->depth++] = $strand->current;
                         $strand->current                 = $value;
                         goto START;
-                    } elseif ($this->promiseAdapter->isThenable($value)) {
+                    } elseif ($this->isPromise($value)) {
                         // !!! increment pending before calling ->then() as it may invoke the callback right away
                         ++$this->pending;
 
+                        if (! $value instanceof Promise) {
+                            $value = $this->promiseAdapter->convertThenable($value);
+                        }
+
                         $this->promiseAdapter
-                            ->convertThenable($value)
                             ->then(
+                                $value,
                                 function ($value) use ($strand) {
                                     $strand->success = true;
                                     $strand->value   = $value;
@@ -478,7 +482,7 @@ class CoroutineExecutor implements Runtime, ExecutorImplementation
     private function completeValueFast(CoroutineContext $ctx, Type $type, $value, array $path, &$returnValue) : bool
     {
         // special handling of Throwable inherited from JS reference implementation, but makes no sense in this PHP
-        if ($this->promiseAdapter->isThenable($value) || $value instanceof Throwable) {
+        if ($this->isPromise($value) || $value instanceof Throwable) {
             return false;
         }
 
@@ -574,7 +578,7 @@ class CoroutineExecutor implements Runtime, ExecutorImplementation
 
         // !!! $value might be promise, yield to resolve
         try {
-            if ($this->promiseAdapter->isThenable($value)) {
+            if ($this->isPromise($value)) {
                 $value = yield $value;
             }
         } catch (Throwable $reason) {
@@ -931,4 +935,14 @@ class CoroutineExecutor implements Runtime, ExecutorImplementation
 
         return $selectedType;
     }
+
+    /**
+     * @param mixed $value
+     *
+     * @return bool
+     */
+    private function isPromise($value)
+    {
+        return $value instanceof Promise || $this->promiseAdapter->isThenable($value);
+    }
 }

tests/GraphQLTest.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace GraphQL\Tests;
+
+use GraphQL\Executor\Promise\Adapter\SyncPromiseAdapter;
+use GraphQL\GraphQL;
+use GraphQL\Type\Definition\ObjectType;
+use GraphQL\Type\Definition\Type;
+use GraphQL\Type\Schema;
+use PHPUnit\Framework\TestCase;
+use function sprintf;
+
+class GraphQLTest extends TestCase
+{
+    public function testPromiseToExecute() : void
+    {
+        $promiseAdapter = new SyncPromiseAdapter();
+        $schema         = new Schema(
+            [
+                'query' => new ObjectType(
+                    [
+                        'name' => 'Query',
+                        'fields' => [
+                            'sayHi' => [
+                                'type' => Type::nonNull(Type::string()),
+                                'args' => [
+                                    'name' => [
+                                        'type' => Type::nonNull(Type::string()),
+                                    ],
+                                ],
+                                'resolve' => static function ($value, $args) use ($promiseAdapter) {
+                                    return $promiseAdapter->createFulfilled(sprintf('Hi %s!', $args['name']));
+                                },
+                            ],
+                        ],
+                    ]
+                ),
+            ]
+        );
+
+        $promise = GraphQL::promiseToExecute($promiseAdapter, $schema, '{ sayHi(name: "John") }');
+        $result  = $promiseAdapter->wait($promise);
+        self::assertSame(['data' => ['sayHi' => 'Hi John!']], $result->toArray());
+    }
+}