@tacaswell
Thomas... are we looking for an image test for this one?
Also, from the other pie based bug I wrote tests for (#2923), you commented that we might only need a png test and can ignore the svg and pdf files.

How do I ignore the svg/pdf files? Can I just leave them out from the commit? Wouldn't that lead to failed tests?

Yes, we are looking for an image test here.

You can specify which extensions to test by passing the extensions kwarg to the decorator:

@image_comparison(..., extensions=['png'])
def test_blah(..)
     pass

See the function in testing.decorators for all of the parameters.

@tacaswell
I started creating the tests but then I thought I made an error, where I branched the fix off the master. I believed that I should have branched it off 1.4.0 or 1.4.x. Then I noticed that there is no 1.4.0 or 1.4.x branch. Should I branch off the master?

Yes, work off of master. We have not cut 1.4 yet.