Knife solo upload not respecting chefignore

I’m using knife-solo (Chef 11.8.0), and when I try to upload a cookbook,
chefignore does not seem to be respected.

I’m uploading the cookbook to my server with:
knife cookbook upload mycookbook

In the top level of my repository, I have an entry in my chefignore file that
says
*~

But, when I run the upload, some temporary files like default.rb~ are being
uploaded to the server.

I also tried putting .~ the chefignore file, but neither seems to work.