Reset Homebrew Formula

You can reset all formulas with: brew update-reset

The update-reset version of this command resets all formulae to be identical to the contents of their remote repositories, deleting any local changes. It is only used as a last-resort effort to fix a problem (it’s like unplugging Homebrew and plugging it back in).

Homebrew recipes are managed via Git, so you can just git checkout freetds.rb to wipe out your local changes.

You need to reset your Cellar git repo.

cd `brew --cellar`
git reset --hard HEAD
brew upgrade <formula>

That should do it!