Unable to fail the test by timeout using the mocha with protractor

I found on mocha web site then we can set the timeout fot it blocks, but looks like it doesn't work for me.

describe('something', function () {
    this.timeout(500);
    it('should take less than 500', function (done) {
        setTimeout(done, 500);
        browser.get('#/dashboard');
    });
})

Run result:

something
  √ should take less than 500 <9849>

Is it posible to get the actual test timeout and compare it? Or I should use expect() to fail the test?

Thank you for any ideas in advance.