how to stub a callback's callback function.

[Zhang Wenlai]

passport.use(new BearerStrategy({ passReqToCallback: true },

function(req, accessToken, done) {
  accessTokens.validate(req, accessToken, function(err, token) {
    if (err) {
      req.log.error(err);
      return done(null, false);
    }
    if (!token) { return done(null, false); }
    
    users.getById(req, token.userId, function(err, user) {
      if (err) {
        req.log.error(err);
        return done(null, false);
      }
      if (!user) { return done(null, false); }

      // default to * for now
      var info = { scope: '*' };
      req.authenticationStrategy = 'OAUTH2';
      req.authToken = accessToken;
      done(null, user, info);
    });
  });

When I stub users.getById function, it excutes original function rather than stub function.

Below is my test:

it('test-error: users getbyId error null for bearer strategy', function(done) { //need to
    var passport = index.__get__("passport");
    var strategy = _.find(passport._strategies, function (value) {
        return value.name === 'bearer'
    })._verify;
    var stub=sinon.stub(users,'getById');
    stub.callsArgWith(2,null,null);
    var accessToken = theToken;
    strategy(context,accessToken,function(err,user){
        assert.isNull(err,"err should be null");
        assert.isFalse(user,"user should be False");
        done();
    });
    users.getById.restore();

});

[Zhang Wenlai]

I've got the solution: I need to stub the top level callback first.

sinon.stub(accessTokens,"validate").callsArgWith(2,null,true);

sinon.stub(users,"getById").callsArgWith(2,null,null);