public function testAccessTokenSetExpiresDirect()
 {
     $token = new AccessToken('testToken', 'bearer', ['expires' => 500]);
     $this->assertTrue($token->isExpired());
     $token = new AccessToken('testToken', 'bearer', ['expires' => time() + 500]);
     $this->assertFalse($token->isExpired());
 }
 /**
  * Get the access token.
  *
  * @return AccessToken|null Oauth2 access token
  */
 public function getAccessToken()
 {
     if (!$this->accessToken instanceof AccessToken || $this->accessToken->isExpired()) {
         $this->acquireAccessToken();
     }
     return $this->accessToken;
 }