Problem with brew updates

[kevdogg]

Getting following error with mac update script:

brew update; brew upgrade;  brew upgrade --cask; brew cleanup;

Error: homebrew-cask is a shallow clone. To `brew update` first run:
  git -C "/usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask" fetch --unshallow
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-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!

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.