From 2f37c60f956d70792b43061e264424b1f15f2457 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Michael=20Lundb=C3=B8l?= <michael@lundboel.dk>
Date: Thu, 16 Mar 2023 00:48:03 +0100
Subject: [PATCH] Cast enums with optional parameters

---
 .../Routing/ImplicitRouteBinding.php           |  2 +-
 src/Illuminate/Support/Reflector.php           |  8 ++++++--
 tests/Routing/ImplicitRouteBindingTest.php     | 18 ++++++++++++++++++
 tests/Routing/RoutingRouteTest.php             | 14 ++++++++++++++
 4 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/src/Illuminate/Routing/ImplicitRouteBinding.php b/src/Illuminate/Routing/ImplicitRouteBinding.php
index d9978af3193a..d3590de1d707 100644
--- a/src/Illuminate/Routing/ImplicitRouteBinding.php
+++ b/src/Illuminate/Routing/ImplicitRouteBinding.php
@@ -84,7 +84,7 @@ protected static function resolveBackedEnumsForRoute($route, $parameters)
 
             $parameterValue = $parameters[$parameterName];
 
-            $backedEnumClass = (string) $parameter->getType();
+            $backedEnumClass = $parameter->getType()?->getName();
 
             $backedEnum = $backedEnumClass::tryFrom((string) $parameterValue);
 
diff --git a/src/Illuminate/Support/Reflector.php b/src/Illuminate/Support/Reflector.php
index 0282378631d7..72609b90db6e 100644
--- a/src/Illuminate/Support/Reflector.php
+++ b/src/Illuminate/Support/Reflector.php
@@ -148,9 +148,13 @@ public static function isParameterSubclassOf($parameter, $className)
      */
     public static function isParameterBackedEnumWithStringBackingType($parameter)
     {
-        $backedEnumClass = (string) $parameter->getType();
+        $backedEnumClass = $parameter->getType();
 
-        if (enum_exists($backedEnumClass)) {
+        if (null === $backedEnumClass) {
+            return false;
+        }
+
+        if (enum_exists($backedEnumClass->getName())) {
             $reflectionBackedEnum = new ReflectionEnum($backedEnumClass);
 
             return $reflectionBackedEnum->isBacked()
diff --git a/tests/Routing/ImplicitRouteBindingTest.php b/tests/Routing/ImplicitRouteBindingTest.php
index 909af4be3e78..675196a11364 100644
--- a/tests/Routing/ImplicitRouteBindingTest.php
+++ b/tests/Routing/ImplicitRouteBindingTest.php
@@ -31,6 +31,24 @@ public function test_it_can_resolve_the_implicit_backed_enum_route_bindings_for_
         $this->assertSame('fruits', $route->parameter('category')->value);
     }
 
+    public function test_it_can_resolve_the_implicit_backed_enum_route_bindings_for_the_given_route_with_optional_parameter()
+    {
+        $action = ['uses' => function (?CategoryBackedEnum $category = null) {
+            return $category->value;
+        }];
+
+        $route = new Route('GET', '/test', $action);
+        $route->parameters = ['category' => 'fruits'];
+
+        $route->prepareForSerialization();
+
+        $container = Container::getInstance();
+
+        ImplicitRouteBinding::resolveForRoute($container, $route);
+
+        $this->assertSame('fruits', $route->parameter('category')->value);
+    }
+
     public function test_it_does_not_resolve_implicit_non_backed_enum_route_bindings_for_the_given_route()
     {
         $action = ['uses' => function (CategoryEnum $category) {
diff --git a/tests/Routing/RoutingRouteTest.php b/tests/Routing/RoutingRouteTest.php
index 5a1a675d5cf5..eeceb390169d 100644
--- a/tests/Routing/RoutingRouteTest.php
+++ b/tests/Routing/RoutingRouteTest.php
@@ -1893,6 +1893,20 @@ public function testImplicitBindingsWithOptionalParameterWithNoKeyInUri()
         $router->dispatch(Request::create('foo', 'GET'))->getContent();
     }
 
+    public function testImplicitBindingsWithOptionalParameterUsingEnumIsAlwaysCastedToEnum()
+    {
+        include 'enums.php';
+
+        $router = $this->getRouter();
+        $router->get('foo/{bar?}', [
+            'middleware' => SubstituteBindings::class,
+            'uses' => function (?\Illuminate\Tests\Routing\CategoryBackedEnum $bar = null) {
+                $this->assertInstanceOf(CategoryBackedEnum::class, $bar);
+            },
+        ]);
+        $router->dispatch(Request::create('foo/people', 'GET'))->getContent();
+    }
+
     public function testImplicitBindingsWithOptionalParameterWithNonExistingKeyInUri()
     {
         $this->expectException(ModelNotFoundException::class);