Browser constructor now accepts an existing Client instance

src/Browser.php

@@ -46,17 +46,19 @@ class Browser extends SearchContext
     /**
      * Class constructor.
      *
-     * @param RequestHandler       $handler  A handler to serve the requests.
-     * @param MessageListener|null $listener An optional message listener to use.
+     * @param Client $httpClient   The HTTP client.
+     * @param bool   $setUserAgent Whether to set the User-Agent header. Defaults to true.
      */
-    public function __construct(RequestHandler $handler, MessageListener $listener = null)
+    public function __construct(Client $httpClient, bool $setUserAgent = true)
     {
-        $this->httpClient = new Client($handler, null, $listener);
-        $this->httpClient->setHeaders([
-            'User-Agent' => 'Brick/Browser'
-        ]);
-
+        $this->httpClient = $httpClient;
         $this->history = new History();
+
+        if ($setUserAgent) {
+            $httpClient->addHeaders([
+                'User-Agent' => 'Brick/Browser v0.2'
+            ]);
+        }
     }
 
     /**

src/Client/Client.php

@@ -232,6 +232,8 @@ public function getLastResponse() : Response
     /**
      * Sets the headers to send with each request.
      *
+     * All existing headers will be replaced.
+     *
      * @param array $headers An associative array of headers.
      *
      * @return static This Client instance.
@@ -243,6 +245,22 @@ public function setHeaders(array $headers) : Client
         return $this;
     }
 
+    /**
+     * Adds headers to send with each request.
+     *
+     * Existing headers with the same name will be overwritten.
+     *
+     * @param array $headers An associative array of headers.
+     *
+     * @return static This Client instance.
+     */
+    public function addHeaders(array $headers) : Client
+    {
+        $this->headers = $headers + $this->headers;
+
+        return $this;
+    }
+
     /**
      * Sets whether to automatically follow redirects.
      *

tests/BrowserTest.php

@@ -4,6 +4,7 @@
 
 use Brick\Browser\Browser;
 use Brick\Browser\By;
+use Brick\Browser\Client\Client;
 use Brick\Browser\Tests\Mock\ApplicationMock;
 
 use PHPUnit\Framework\TestCase;
@@ -49,7 +50,7 @@ private function assertUrl(string $url, Browser $browser) : void
     public function testBrowser() : void
     {
         $application = new ApplicationMock();
-        $browser = new Browser($application);
+        $browser = new Browser(new Client($application));
 
         $browser->open('http://example.com/');