Set an implicit wait for selenium.

[Florian Apolloner]

Selenium often tries to access elements before the page is loaded; it offers an implicitly_wait method which we could utilize and it might fix a few of our timing issues; I'd suggest a relatively high timeout of 10 seconds to cover our bases. See ​https://github.com/SeleniumHQ/selenium/blob/master/py/selenium/webdriver/remote/webdriver.py#L626 for this method.

[bsilverberg]

I have opened pull request ​https://github.com/django/django/pull/2543 for this. This is my first django pull request so any advice/feedback would be appreciated.

[Jeremy Bowman]

I'd advise a little caution on this approach. I've worked on projects which have assertions that just want to verify that an element is not on the page. If every such assertion takes 10 seconds of redundantly verifying that the element is still not on the page, that can make the tests take a lot longer to run. It's a pain to correctly do it consistently, but I've had better results fixing tests with implicit timing dependencies to wait explicitly when appropriate.

[bsilverberg]

Thanks jmbowman. That certainly can be an issue. I ran the current test suite and it doesn't seem to suffer from this issue. In the suites that we use at work we do have a default implicit wait set up, and then we use helper methods when we want to check that an element is not present which switch off the implicit wait.

I think the approach used here is appropriate for the current test suite, but it is something to be careful about in the future, if this approach is adopted.

[Tim Graham]

I left an idea for improvement on the pull request.

@apollo13, any thoughts on the comments in the thread? Was the idea to commit this and see if it helps with the random failures on Jenkins?

[Florian Apolloner]

We currently don't have any random failures (or at least not really often), so I think we can close this for now.