'first page', 'Page.md' => 'another page', 'somefile.css' => 'body {}', '22.png' => '', ]; $root = vfsStream::setup('root', null, $structure); $config = ConfigBuilder::withMode(Daux::LIVE_MODE) ->withDocumentationDirectory($root->url()) ->build(); $daux = new Daux($config, new NullOutput()); $daux->generateTree(); $page = new RawPage($daux->tree['somefile.css']->getPath()); $server = new Server($daux); $response = $server->createResponse($page)->prepare(Request::createFromGlobals()); $this->assertEquals('text/css', $response->headers->get('Content-Type')); } }