问使用Firebase Auth进行身份验证时注销Facebook用户

EN

func authenticateWithFacebook() {
    FBSDKLoginManager().logIn(withReadPermissions: ["public_profile"], from: self) { (user, error) in // Signs up user with Facebook
        if let error = error {
            print(error.localizedDescription)
        } else if (user!.isCancelled) { // User cancels sign up
            print("User Cancelled")
        } else {
            self.authenticateFacebookUserWithFirebase(credential: FacebookAuthProvider.credential(withAccessToken: FBSDKAccessToken.current().tokenString))
        }
    }
}

func authenticateFacebookUserWithFirebase(credential: AuthCredential) {
    Auth.auth().signInAndRetrieveData(with: credential) { (user, error) in
        if let error = error {
            print(error.localizedDescription)
        } else {
            print("Success")
        }
    }
}