brew update failure while executing git checkout

Question

After an interrupted brew update because of a network issue, Homebrew appears to be broken:

$ brew update
error: pathspec \'master\' did not match a         


        

Answer 1

Fixed with the following commands:

$ cd `brew --prefix`
$ git remote add origin https://github.com/Homebrew/homebrew.git
$ git fetch origin
$ git reset --hard origin/master
$ brew update
Already up-to-date.