Resolve anonymous class return type to object

packages/NodeTypeResolver/src/NodeTypeResolver.php

@@ -35,6 +35,7 @@
 use PHPStan\Type\MixedType;
 use PHPStan\Type\NullType;
 use PHPStan\Type\ObjectType;
+use PHPStan\Type\ObjectWithoutClassType;
 use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use PHPStan\Type\UnionType;
@@ -297,6 +298,12 @@ public function getNodeStaticType(Node $node): ?Type
             return null;
         }
 
+        if ($node instanceof New_) {
+            if ($this->isAnonymousClass($node->class)) {
+                return new ObjectWithoutClassType();
+            }
+        }
+
         return $nodeScope->getType($node);
     }
 
@@ -410,8 +417,7 @@ private function resolveFirstTypes(Node $node): array
 
         // skip anonymous classes, ref https://github.com/rectorphp/rector/issues/1574
         if ($node instanceof New_) {
-            $className = $this->nameResolver->resolve($node->class);
-            if ($className === null || Strings::contains($className, 'AnonymousClass')) {
+            if ($this->isAnonymousClass($node->class)) {
                 return [];
             }
         }
@@ -556,4 +562,15 @@ private function getClassNodeProperty(Class_ $class, string $name): ?PropertyPro
 
         return null;
     }
+
+    private function isAnonymousClass(Node $node): bool
+    {
+        if (! $node instanceof Class_) {
+            return false;
+        }
+
+        $className = $this->nameResolver->resolve($node);
+
+        return $className === null || Strings::contains($className, 'AnonymousClass');
+    }
 }

packages/NodeTypeResolver/src/StaticTypeToStringResolver.php

@@ -10,6 +10,7 @@
 use PHPStan\Type\IntegerType;
 use PHPStan\Type\NullType;
 use PHPStan\Type\ObjectType;
+use PHPStan\Type\ObjectWithoutClassType;
 use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
 use PHPStan\Type\UnionType;
@@ -26,6 +27,7 @@ public function __construct(CallableCollectorPopulator $callableCollectorPopulat
     {
         $resolvers = [
             IntegerType::class => ['int'],
+            ObjectWithoutClassType::class => ['object'],
             ClosureType::class => ['callable'],
             CallableType::class => ['callable'],
             FloatType::class => ['float'],

packages/TypeDeclaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/a_new_class.php.inc

@@ -0,0 +1,27 @@
+<?php
+
+namespace Rector\TypeDeclaration\Tests\Rector\ClassMethod\ReturnTypeDeclarationRector\Fixture;
+
+class ANewClass
+{
+    public function getObject()
+    {
+        return new class() {};
+    }
+}
+
+?>
+-----
+<?php
+
+namespace Rector\TypeDeclaration\Tests\Rector\ClassMethod\ReturnTypeDeclarationRector\Fixture;
+
+class ANewClass
+{
+    public function getObject(): object
+    {
+        return new class() {};
+    }
+}
+
+?>

packages/TypeDeclaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/ReturnTypeDeclarationRectorTest.php

@@ -53,6 +53,8 @@ public function test(): void
             __DIR__ . '/Fixture/dunglas/BazTrait.php.inc',
             __DIR__ . '/Fixture/dunglas/Child.php.inc',
             __DIR__ . '/Fixture/dunglas/nullable_types.php.inc',
+            // anonymous class
+            __DIR__ . '/Fixture/a_new_class.php.inc',
         ];
 
         $this->doTestFiles($integrationFiles);