diff --git a/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php b/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php
index a78234470fc7..059aa48b6d57 100644
--- a/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php
+++ b/src/Illuminate/Foundation/Testing/Concerns/MakesHttpRequests.php
@@ -12,93 +12,93 @@
 trait MakesHttpRequests
 {
     /**
-     * Additional server variables for the request.
+     * Additional headers for the request.
      *
      * @var array
      */
-    protected $serverVariables = [];
+    protected $defaultHeaders = [];
 
     /**
-     * Additional headers for the request.
+     * Additional server variables for the request.
      *
      * @var array
      */
-    protected $defaultHeaders = [];
+    protected $serverVariables = [];
 
     /**
-     * Define a set of server variables to be sent with the requests.
+     * Define additional headers to be sent with the request.
      *
-     * @param  array  $server
+     * @param  array $headers
      * @return $this
      */
-    public function withServerVariables(array $server)
+    public function withHeaders(array $headers)
     {
-        $this->serverVariables = $server;
+        $this->defaultHeaders = array_merge($this->defaultHeaders, $headers);
 
         return $this;
     }
 
     /**
-     * Disable middleware for the test.
+     * Add a header to be sent with the request.
      *
-     * @param  string|array  $middleware
+     * @param  string $name
+     * @param  string $value
      * @return $this
      */
-    public function withoutMiddleware($middleware = null)
+    public function withHeader(string $name, string $value)
     {
-        if (is_null($middleware)) {
-            $this->app->instance('middleware.disable', true);
-
-            return $this;
-        }
-
-        foreach ((array) $middleware as $abstract) {
-            $this->app->instance($abstract, new class {
-                public function handle($request, $next)
-                {
-                    return $next($request);
-                }
-            });
-        }
+        $this->defaultHeaders[$name] = $value;
 
         return $this;
     }
 
     /**
-     * Define a set of headers to be sent with the requests.
+     * Flush all the configured headers.
      *
-     * @param array $headers
      * @return $this
      */
-    public function withHeaders(array $headers)
+    public function flushHeaders()
     {
-        $this->defaultHeaders = $headers;
+        $this->defaultHeaders = [];
 
         return $this;
     }
 
     /**
-     * Adds a header to be sent with the requests.
+     * Define a set of server variables to be sent with the requests.
      *
-     * @param  string $name
-     * @param  string $value
+     * @param  array  $server
      * @return $this
      */
-    public function withHeader(string $name, string $value)
+    public function withServerVariables(array $server)
     {
-        $this->defaultHeaders[$name] = $value;
+        $this->serverVariables = $server;
 
         return $this;
     }
 
     /**
-     * Removes all the predefined headers to be sent with the requests.
+     * Disable middleware for the test.
      *
+     * @param  string|array  $middleware
      * @return $this
      */
-    public function cleanHeaders()
+    public function withoutMiddleware($middleware = null)
     {
-        $this->defaultHeaders = [];
+        if (is_null($middleware)) {
+            $this->app->instance('middleware.disable', true);
+
+            return $this;
+        }
+
+        foreach ((array) $middleware as $abstract) {
+            $this->app->instance($abstract, new class {
+                public function handle($request, $next)
+                {
+                    return $next($request);
+                }
+            });
+        }
 
         return $this;
     }
@@ -326,24 +326,13 @@ protected function prepareUrlForRequest($uri)
      */
     protected function transformHeadersToServerVars(array $headers)
     {
-        return collect($this->mergeDefaultHeaders($headers))->mapWithKeys(function ($value, $name) {
+        return collect(array_merge($this->defaultHeaders, $headers))->mapWithKeys(function ($value, $name) {
             $name = strtr(strtoupper($name), '-', '_');
 
             return [$this->formatServerHeaderKey($name) => $value];
         })->all();
     }
 
-    /**
-     * Merges the given headers and the default request headers.
-     *
-     * @param  array  $headers
-     * @return array
-     */
-    protected function mergeDefaultHeaders(array $headers)
-    {
-        return array_merge($headers, $this->defaultHeaders);
-    }
-
     /**
      * Format the header name for the server array.
      *