Homebrew: Error: update-report should not be called directly

brew upgrade will upgrade all installed packages. If you need to maintain a specific version of any binary, consider using @thanh-hải's answer: https://stackoverflow.com/a/38464247/868724

I just got this error. I ran brew upgrade and then brew update again and the problem seemed to resolve itself.

Alternatively, try just running brew update again as suggested by @ashley-willis.

Edit : run cd "$(brew --repository)" && git fetch && git reset --hard origin/master will solve!

Refer to https://github.com/Homebrew/brew/issues/557

Running brew update again after getting this error works, as I saw suggested on https://discuss.circleci.com/t/brew-update-command-fails/5211 and worked for me as well, without doing any upgrades nor git-fu