From b524b65ec62be1929ec24ab0703a199983031ded Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tom=20Moitie=CC=81?= <tom.moitie@deskpro.com>
Date: Thu, 11 Jun 2026 12:54:29 +0100
Subject: [PATCH] Pass scalar overrides explicitly to keep lazy type loading
 lazy

On webonyx/graphql-php >= 15.31.0, the first lookup of a built-in scalar
triggers scalar-override discovery, which resolves the lazy types callable
and eagerly builds every type in the schema from the AST on every request.

When SchemaConfig::setScalarOverrides is available, determine the overrides
cheaply from the document AST and pass them explicitly so the scan is
skipped and the types callable stays unresolved.

Fixes #2771.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---
 CHANGELOG.md                            |  4 ++
 src/Schema/SchemaBuilder.php            | 18 ++++++++
 tests/Unit/Schema/SchemaBuilderTest.php | 55 +++++++++++++++++++++++++
 3 files changed, 77 insertions(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 65a8992ad8..f8975c0931 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,10 @@ You can find and compare releases at the [GitHub release page](https://github.co
 
 ## Unreleased
 
+### Fixed
+
+- Keep lazy type loading lazy on `webonyx/graphql-php >= 15.31.0` by passing scalar overrides explicitly when `SchemaConfig::setScalarOverrides` is available https://github.com/nuwave/lighthouse/pull/2772
+
 ## v6.67.0
 
 ### Changed
diff --git a/src/Schema/SchemaBuilder.php b/src/Schema/SchemaBuilder.php
index b6df5884f1..d5bdce4395 100644
--- a/src/Schema/SchemaBuilder.php
+++ b/src/Schema/SchemaBuilder.php
@@ -4,6 +4,7 @@
 
 use GraphQL\GraphQL;
 use GraphQL\Type\Definition\ObjectType;
+use GraphQL\Type\Definition\ScalarType;
 use GraphQL\Type\Definition\Type;
 use GraphQL\Type\Schema;
 use GraphQL\Type\SchemaConfig;
@@ -70,6 +71,23 @@ protected function build(DocumentAST $documentAST): Schema
             fn (): array => $this->typeRegistry->possibleTypes(),
         );
 
+        // Passing scalar overrides explicitly prevents the first lookup of a built-in scalar
+        // from discovering them by resolving the lazy types callable, which would eagerly
+        // build every type in the schema, see https://github.com/nuwave/lighthouse/issues/2771.
+        // TODO remove this check when the minimum version of webonyx/graphql-php includes the method
+        if (method_exists($config, 'setScalarOverrides')) {
+            $scalarOverrides = [];
+            foreach (Type::BUILT_IN_SCALAR_NAMES as $name) {
+                if (isset($documentAST->types[$name])) {
+                    $type = $this->typeRegistry->get($name);
+                    assert($type instanceof ScalarType);
+                    $scalarOverrides[] = $type;
+                }
+            }
+
+            $config->setScalarOverrides($scalarOverrides);
+        }
+
         // There is no way to resolve directives lazily, so we convert them eagerly
         $directiveFactory = new DirectiveFactory(
             new ExecutableTypeNodeConverter($this->typeRegistry),
diff --git a/tests/Unit/Schema/SchemaBuilderTest.php b/tests/Unit/Schema/SchemaBuilderTest.php
index a9962c8a56..a7db0da6ca 100644
--- a/tests/Unit/Schema/SchemaBuilderTest.php
+++ b/tests/Unit/Schema/SchemaBuilderTest.php
@@ -8,9 +8,13 @@
 use GraphQL\Type\Definition\InputObjectType;
 use GraphQL\Type\Definition\InterfaceType;
 use GraphQL\Type\Definition\ObjectType;
+use GraphQL\Type\Definition\ScalarType;
+use GraphQL\Type\Definition\Type;
 use Nuwave\Lighthouse\Schema\RootType;
 use Nuwave\Lighthouse\Schema\SchemaBuilder;
+use Nuwave\Lighthouse\Schema\TypeRegistry;
 use Tests\TestCase;
+use Tests\Utils\Scalars\Email;
 
 final class SchemaBuilderTest extends TestCase
 {
@@ -209,6 +213,57 @@ public function testExtendTypes(): void
         $this->assertSame('yo?', $type->getField('bar')->description);
     }
 
+    public function testRegistersExplicitlyEmptyScalarOverrides(): void
+    {
+        $schema = $this->buildSchemaWithPlaceholderQuery('');
+
+        $config = $schema->getConfig();
+        if (! method_exists($config, 'getScalarOverrides')) {
+            $this->markTestSkipped('Requires a version of webonyx/graphql-php that supports SchemaConfig::setScalarOverrides.');
+        }
+
+        $this->assertSame([], $config->getScalarOverrides());
+    }
+
+    public function testRegistersRedefinedBuiltInScalarsAsScalarOverrides(): void
+    {
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        scalar String @scalar(class: "Email")
+        ');
+
+        $config = $schema->getConfig();
+        if (! method_exists($config, 'getScalarOverrides')) {
+            $this->markTestSkipped('Requires a version of webonyx/graphql-php that supports SchemaConfig::setScalarOverrides.');
+        }
+
+        $scalarOverrides = $config->getScalarOverrides();
+        $this->assertNotNull($scalarOverrides);
+        $this->assertCount(1, $scalarOverrides);
+
+        $stringOverride = reset($scalarOverrides);
+        $this->assertInstanceOf(Email::class, $stringOverride);
+        $this->assertSame(Type::STRING, $stringOverride->name);
+    }
+
+    public function testBuiltInScalarLookupDoesNotResolveAllTypes(): void
+    {
+        if (! method_exists(SchemaConfig::class, 'setScalarOverrides')) {
+            $this->markTestSkipped('Requires a version of webonyx/graphql-php that supports SchemaConfig::setScalarOverrides.');
+        }
+
+        $schema = $this->buildSchemaWithPlaceholderQuery(/** @lang GraphQL */ '
+        type Foo {
+            bar: Int
+        }
+        ');
+
+        $booleanType = $schema->getType(Type::BOOLEAN);
+        $this->assertInstanceOf(ScalarType::class, $booleanType);
+
+        $typeRegistry = $this->app->make(TypeRegistry::class);
+        $this->assertArrayNotHasKey('Foo', $typeRegistry->resolvedTypes());
+    }
+
     public function testResolvesEnumDefaultValuesToInternalValues(): void
     {
         $schema = $this->buildSchema(/** @lang GraphQL */ <<<'GRAPHQL'