Reset the cookie file so that it refers to the specified user.
$uid User id to set as the active session.:
function sessionReset($uid = 0) {
// Close the internal browser.
$this
->curlClose();
$this->loggedInUser = FALSE;
// Change cookie file for user.
$this->cookieFile = file_stream_wrapper_get_instance_by_scheme('temporary')
->getDirectoryPath() . '/cookie.' . $uid . '.txt';
$this->additionalCurlOptions[CURLOPT_COOKIEFILE] = $this->cookieFile;
$this->additionalCurlOptions[CURLOPT_COOKIESESSION] = TRUE;
$this
->drupalGet('session-test/get');
$this
->assertResponse(200, 'Session test module is correctly enabled.', 'Session');
}