Add simple test for GH 28448
- [x] closes #28448
- [x] tests added / passed
- [x] passes `black pandas`
- [x] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

Won't have a chance to look at this anytime soon, so don't wait for me.

On Wed, Oct 30, 2019 at 12:12 PM William Ayd <notifications@github.com>
wrote:

> *@WillAyd* approved this pull request.
>
> lgtm @TomAugspurger <https://github.com/TomAugspurger> or @jbrockmendel
> <https://github.com/jbrockmendel> feel free to merge if it looks good to
> you as well
>
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 small comment, not a blocker.  lgtm thanks @MarcoGorelli 