[11.x] Add option to disable merging of base configuration

src/Illuminate/Contracts/Foundation/Application.php

@@ -237,6 +237,11 @@ public function setLocale($locale);
      */
     public function shouldSkipMiddleware();
 
+    /**
+     * @return bool
+     */
+    public function shouldMergeBaseConfiguration();
+
     /**
      * Register a terminating callback with the application.
      *

src/Illuminate/Foundation/Application.php

@@ -201,6 +201,11 @@ class Application extends Container implements ApplicationContract, CachesConfig
      */
     protected $absoluteCachePathPrefixes = ['/', '\\'];
 
+    /**
+     * @var bool
+     */
+    protected $mergeBaseConfiguration = true;
+
     /**
      * Create a new Illuminate application instance.
      *
@@ -1209,6 +1214,24 @@ public function shouldSkipMiddleware()
                $this->make('middleware.disable') === true;
     }
 
+    /**
+     * @return $this
+     */
+    public function dontMergeBaseConfiguration()
+    {
+        $this->mergeBaseConfiguration = false;
+
+        return $this;
+    }
+
+    /**
+     * @return bool
+     */
+    public function shouldMergeBaseConfiguration()
+    {
+        return $this->mergeBaseConfiguration;
+    }
+
     /**
      * Get the path to the cached services.php file.
      *

src/Illuminate/Foundation/Bootstrap/LoadConfiguration.php

@@ -66,7 +66,9 @@ protected function loadConfigurationFiles(Application $app, RepositoryContract $
         //     throw new Exception('Unable to load the "app" configuration file.');
         // }
 
-        $base = $this->getBaseConfiguration();
+        $base = $app->shouldMergeBaseConfiguration()
+            ? $this->getBaseConfiguration()
+            : [];
 
         foreach ($files as $name => $path) {
             $base = $this->loadConfigurationFile($repository, $name, $path, $base);

tests/Foundation/Bootstrap/LoadConfigurationTest.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace Illuminate\Tests\Foundation\Bootstrap;
+
+use Illuminate\Foundation\Application;
+use Illuminate\Foundation\Bootstrap\LoadConfiguration;
+use PHPUnit\Framework\TestCase;
+
+class LoadConfigurationTest extends TestCase
+{
+    public function testLoadsBaseConfiguration()
+    {
+        $app = new Application();
+
+        (new LoadConfiguration())->bootstrap($app);
+
+        $this->assertSame('Laravel', $app['config']['app.name']);
+    }
+
+    public function testDontLoadBaseConfiguration()
+    {
+        $app = new Application();
+        $app->dontMergeBaseConfiguration();
+
+        (new LoadConfiguration())->bootstrap($app);
+
+        $this->assertNull($app['config']['app.name']);
+    }
+}