Selenium-webdriver.wait(): what gets returned?

Question

Running a Mocha test, using Selenium-Webdriver, I have

driver.get(destinationPage);
driver.wait(function() {
  return driver.isElementPresent(By.xpath(xpathLocation));
}, 3000);
driver.findElement(By.xpath(xpathLocation))
      .sendkeys('87654321');
done();

But, I am getting the error TypeError: Object [object Object] has no method 'sendkeys'

Why would that be? What (if anything) is returned by wait()?

Thank you!