Welllll this happened:
Error:
homebrew-core is a shallow clone.
To `brew update`, first run:
git -C /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core fetch --unshallow
This command may take a few minutes to run due to the large size of the repository.
This restriction has been made on GitHub's request because updating shallow
clones is an extremely expensive operation due to the tree layout and traffic of
Homebrew/homebrew-core and Homebrew/homebrew-cask. We don't do this for you
automatically to avoid repeatedly performing an expensive unshallow operation in
CI systems (which should instead be fixed to not use shallow clones). Sorry for
the inconvenience!
Failed during: /usr/local/bin/brew update --force --quiet
==> Downloading
https://formulae.brew.sh/api/formula.jws.json
################################################## ####################### 100.0%
==> Downloading
https://formulae.brew.sh/api/cask.jws.json
################################################## ####################### 100.0%
Warning: p7zip 17.05 is already installed and up-to-date.
To reinstall 17.05, run:
brew reinstall p7zip
Warning: unar 1.10.8_4 is already installed and up-to-date.
To reinstall 1.10.8_4, run:
brew reinstall unar
It looks to me as if P7 and unar whatever the heck they may be are already installed???