From 33f3cf65b26cee786398cb7e12b689f6c4ac70ed Mon Sep 17 00:00:00 2001
From: Ruud Kamphuis <ruudk@users.noreply.github.com>
Date: Thu, 28 Oct 2021 12:49:33 +0200
Subject: [PATCH 1/2] Allow types to be returned using `yield`

Instead of checking for `array` or `callable`, why not check for `iterable` intead.

This makes it possible to use `yield` to provide types.
---
 src/Type/Definition/FieldDefinition.php |  5 +++--
 src/Type/Definition/InputObjectType.php |  5 +++--
 tests/Type/DefinitionTest.php           | 26 +++++++++++++++++++++++++
 3 files changed, 32 insertions(+), 4 deletions(-)

diff --git a/src/Type/Definition/FieldDefinition.php b/src/Type/Definition/FieldDefinition.php
index 0cfd5e18f..a2e824c6c 100644
--- a/src/Type/Definition/FieldDefinition.php
+++ b/src/Type/Definition/FieldDefinition.php
@@ -11,6 +11,7 @@
 
 use function is_array;
 use function is_callable;
+use function is_iterable;
 use function is_string;
 use function sprintf;
 
@@ -86,9 +87,9 @@ public static function defineFieldMap(Type $type, $fields): array
             $fields = $fields();
         }
 
-        if (! is_array($fields)) {
+        if (! is_iterable($fields)) {
             throw new InvariantViolation(
-                "{$type->name} fields must be an array or a callable which returns such an array."
+                "{$type->name} fields must be an iterable or a callable which returns such an iterable."
             );
         }
 
diff --git a/src/Type/Definition/InputObjectType.php b/src/Type/Definition/InputObjectType.php
index f78420b9b..9eee526ec 100644
--- a/src/Type/Definition/InputObjectType.php
+++ b/src/Type/Definition/InputObjectType.php
@@ -13,6 +13,7 @@
 use function count;
 use function is_array;
 use function is_callable;
+use function is_iterable;
 use function is_string;
 use function sprintf;
 
@@ -96,9 +97,9 @@ protected function initializeFields(): void
             $fields = $fields();
         }
 
-        if (! is_array($fields)) {
+        if (! is_iterable($fields)) {
             throw new InvariantViolation(
-                sprintf('%s fields must be an array or a callable which returns such an array.', $this->name)
+                sprintf('%s fields must be an iterable or a callable which returns such an iterable.', $this->name)
             );
         }
 
diff --git a/tests/Type/DefinitionTest.php b/tests/Type/DefinitionTest.php
index 647957671..303740577 100644
--- a/tests/Type/DefinitionTest.php
+++ b/tests/Type/DefinitionTest.php
@@ -5,6 +5,7 @@
 namespace GraphQL\Tests\Type;
 
 use DMS\PHPUnitExtensions\ArraySubset\ArraySubsetAsserts;
+use Generator;
 use GraphQL\Error\InvariantViolation;
 use GraphQL\Tests\Type\TestClasses\MyCustomType;
 use GraphQL\Tests\Type\TestClasses\OtherCustom;
@@ -14,9 +15,11 @@
 use GraphQL\Type\Definition\InputObjectField;
 use GraphQL\Type\Definition\InputObjectType;
 use GraphQL\Type\Definition\InterfaceType;
+use GraphQL\Type\Definition\IntType;
 use GraphQL\Type\Definition\ListOfType;
 use GraphQL\Type\Definition\NonNull;
 use GraphQL\Type\Definition\ObjectType;
+use GraphQL\Type\Definition\StringType;
 use GraphQL\Type\Definition\Type;
 use GraphQL\Type\Definition\UnionType;
 use GraphQL\Type\Schema;
@@ -2040,4 +2043,27 @@ public function testThrowsWhenLazyLoadedFieldHasInvalidArgs(): void
 
         $objType->assertValid();
     }
+
+    public function testReturningFieldsUsingYield()
+    {
+        $type = new ObjectType([
+            'name'   => 'Query',
+            'fields' => static function (): Generator {
+                yield 'url'    => ['type' => Type::string()];
+                yield 'width'  => ['type' => Type::int()];
+            },
+        ]);
+
+        $blogSchema = new Schema(['query' => $type]);
+
+        self::assertSame($blogSchema->getQueryType(), $type);
+
+        $field = $type->getField('url');
+        self::assertSame($field->name, 'url');
+        self::assertInstanceOf(StringType::class, $field->getType());
+
+        $field = $type->getField('width');
+        self::assertSame($field->name, 'width');
+        self::assertInstanceOf(IntType::class, $field->getType());
+    }
 }

From 59d5d66fdfe3e2bf0d674eb59a03b69aa6fb7e41 Mon Sep 17 00:00:00 2001
From: Benedikt Franke <benedikt@franke.tech>
Date: Thu, 28 Oct 2021 16:52:31 +0200
Subject: [PATCH 2/2] Update CHANGELOG.md

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index ff98273f8..4d863d458 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,6 +33,7 @@ You can find and compare releases at the [GitHub release page](https://github.co
 - Expose structured enumeration of directive locations
 - Add `AST::concatAST()` utility
 - Allow lazy input object fields
+- Allow field definitions to be defined as any `iterable`, not just `array`
 
 ### Optimized