brew-tap's install action, doesn't actually update taps

[frdmn]

Just noticed that bork do ok brew-tap <tap> doesn't actually update the (indeed outdated) tap:

❯ bork do ok brew-tap frdmn/formulas
ok: brew-tap frdmn/formulas

According to the Homebrew docs, the brew update command is used to update them.

Can someone double check and maybe confirm this bug?

[mattly]

I think this is actually the intended behavior, as the ok brew-tap some/tap statement represents "have you added the tap or not, and is it pinned or not?", and it doesn't seem homebrew offers a way to keep taps updated individually outside of the all-at-once update of brew update. It does seem a bit counterintuitive, so I will add some info to the docs about that.