How to make Selenium tests reliable, scalable, and maintainable(lucidchart.com)

  > getWithRetry takes a function with a return value
  > 
  >   def numberOfChildren(implicit user: LucidUser): Int = {
  >    getWithRetry() {
  >      user.driver.getCssElement(visibleCss).children.size
  >    }
  >   }
  > 
  > predicateWithRetry takes function that returns a boolean and will retry on any false values
  > 
  >   def onPage(implicit user: LucidUser): Boolean = {
  >    predicateWithRetry() {
  >      user.driver.getCurrentUrl.contains(pageUrl)
  >    }
  >   }

  def miniguide_is_up():
      return match("miniguide.png")

  press(Key.INFO)
  assert wait_until(miniguide_is_up)
  # or:
  if wait_until(miniguide_is_up): ...

  > doWithRetry takes a function with no return type
  >
  >   def clickFillColorWell(implicit user: LucidUser) {
  >    doWithRetry() {
  >      user.clickElementByCss("#fill-colorwell-color-well-wrapper")
  >    }

  do_until(
      lambda: press(Key.INFO),
      miniguide_is_up)

  # Could get into an infinite loop if the system-under-test fails
  while not miniguide_is_up():
      press(Key.INFO)

  # This is very verbose, and it uses an obscure Python feature: `for...else`[2]
  for _ in range(10):
      press(Key.INFO)
      if miniguide_is_up():
          break
  else:
      assert False, "Miniguide didn't appear after pressing INFO 10 times"