[8.x] Create getter for the middleware priority (#37271)

* Create getter for the middleware priority

This getter will help to create tests to ensure that middlewares are
registered in the right priority.

My use case for this is a middleware that I want to ensure gets
registered after the `StartSession` but right before the
`AuthenticatesRequests` one. With this getter I can use their indexes to
write a test for it.

* Update Kernel.php

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Illuminate/Foundation/Http/Kernel.php

@@ -383,6 +383,16 @@ protected function syncMiddlewareToRouter()
         }
     }
 
+    /**
+     * Get the priority-sorted list of middleware.
+     *
+     * @return array
+     */
+    public function getMiddlewarePriority()
+    {
+        return $this->middlewarePriority;
+    }
+
     /**
      * Get the bootstrap classes for the application.
      *

tests/Foundation/Http/KernelTest.php

@@ -24,6 +24,22 @@ public function testGetRouteMiddleware()
         $this->assertEquals([], $kernel->getRouteMiddleware());
     }
 
+    public function testGetMiddlewarePriority()
+    {
+        $kernel = new Kernel($this->getApplication(), $this->getRouter());
+
+        $this->assertEquals([
+            \Illuminate\Cookie\Middleware\EncryptCookies::class,
+            \Illuminate\Session\Middleware\StartSession::class,
+            \Illuminate\View\Middleware\ShareErrorsFromSession::class,
+            \Illuminate\Contracts\Auth\Middleware\AuthenticatesRequests::class,
+            \Illuminate\Routing\Middleware\ThrottleRequests::class,
+            \Illuminate\Session\Middleware\AuthenticateSession::class,
+            \Illuminate\Routing\Middleware\SubstituteBindings::class,
+            \Illuminate\Auth\Middleware\Authorize::class,
+        ], $kernel->getMiddlewarePriority());
+    }
+
     /**
      * @return \Illuminate\Contracts\Foundation\Application
      */