Yanked release support

[shirblc]

Hi,

I'm using CFFI in my project, and over the past few days I've had repeated PRs from pyup to update it to the so-called latest version (1.14.3). Since pip couldn't find it I dug into pypi (where CFFI 1.14.2 is marked as the latest) and found that this release was apparently yanked (see here). And yet, for some reason, pyup continues to suggest that version as the latest.

I'm only using pyup.io, but in case it's needed anyway, the project runs on macOS 10.15.6, using python 3.8. Not sure if this is a bug report or feature request, but since the authors or CFFI pulled that release, I'm not sure what value there is in constantly suggesting it (or any other yanked release, unless specifically asked for).

Thank you!

[Harmon758]

I'm also encountering this with setuptools 51.1.0.post20201221 (pypa/setuptools#2500).