diff --git a/src/Rector/RootResolverSignatureRector.php b/src/Rector/RootResolverSignatureRector.php
index 33e1c2243..5bdf2e339 100644
--- a/src/Rector/RootResolverSignatureRector.php
+++ b/src/Rector/RootResolverSignatureRector.php
@@ -206,11 +206,11 @@ protected function isUselessSingleRootParam(ClassMethod $method): bool
             $type = $type->type;
         }
 
-        if ($type instanceof Identifier && $type->name === 'array') {
-            return false;
+        if (! $type instanceof Identifier) {
+            return true;
         }
 
-        return true;
+        return $type->name !== 'array';
     }
 
     protected function prependRootParam(ClassMethod $method): void
diff --git a/tests/Unit/Rector/RootResolverSignatureRector/bootstrap.php b/tests/Unit/Rector/RootResolverSignatureRector/bootstrap.php
index af171e961..9d10e9116 100644
--- a/tests/Unit/Rector/RootResolverSignatureRector/bootstrap.php
+++ b/tests/Unit/Rector/RootResolverSignatureRector/bootstrap.php
@@ -8,6 +8,33 @@
 
 define('LIGHTHOUSE_RECTOR_BOOTSTRAP_LOADED', true);
 
+$errorHandler = set_error_handler(static fn (mixed ...$args): bool => false);
+restore_error_handler();
+$exceptionHandler = set_exception_handler(static fn (mixed ...$args) => null);
+restore_exception_handler();
+
 require_once __DIR__ . '/../../../../vendor/larastan/larastan/bootstrap.php';
 
+// Undo handlers registered by Laravel's HandleExceptions bootstrapper
+// to avoid PHPUnit risky test warnings about leaked handlers.
+for ($i = 0; $i < 10; ++$i) {
+    if (set_error_handler(static fn (mixed ...$args): bool => false) === $errorHandler) {
+        restore_error_handler();
+        break;
+    }
+
+    restore_error_handler();
+    restore_error_handler();
+}
+
+for ($i = 0; $i < 10; ++$i) {
+    if (set_exception_handler(static fn (mixed ...$args) => null) === $exceptionHandler) {
+        restore_exception_handler();
+        break;
+    }
+
+    restore_exception_handler();
+    restore_exception_handler();
+}
+
 config()->set('lighthouse', require __DIR__ . '/../../../../src/lighthouse.php');