Yarn cache not cleaned up after recent fixes

[andykant]

I've started tracking master until there's another release as suggested, but I noticed an additional issue with the #439/#459 fixes: If Heroku had the previous .cache directory cached, those files will continue to exist and throw errors until manually cleaned up. Aside from that, I can verify that #459 fixed my issues.

I worked around this by temporarily pushing rimraf .cache as part of my build to clean things up on the Heroku side, which fixed it.

[jmorrell]

Hi @andykant! I've released the buildpack changes, so you should be able to point back to the canonical buildpack.

If Heroku had the previous .cache directory cached

I was trying to puzzle out how this might have worked. Are you saying that you specifically added the cached directory in your package.json? We don't cache these directories by default. If not, I'm not sure how it ended up in your Heroku cache.

We also invalidate the cache anytime you use a new version of anything, so bumping your version of node or npm would be an easier solution than adding a special command.

[andykant]

This was specifically occurring in Heroku CI (if that happens to cache things a bit differently). I don't have reproduction steps though and I've been able to fix it in my Heroku CI, so I'll close the issue.

Thanks for your time and for the prior fix!