Mercurial already has this as well: hg annotate --help ... -w --ignore-all-space ignore white space when comparing lines -b --ignore-space-change ig

Mercurial already has this as well: hg annotate --help ... -w --ignore-all-space ignore white space when comparing lines -b --ignore-space-change ignore changes in the amount of white space -B --ignore-blank-lines ignore changes whose lines are all blank