a4bada575a
The `cask` attribute doesn't make as much sense on Linux but can be ignored there. The advantage of this change is that (like #4086) it allows figuring out the relevant cask for a formulae requirement on a Linux machine.
Library
This directory contains all the code run by the official brew and brew cask commands in Homebrew and all formulae (package descriptions) in taps (repositories containing formulae) in Taps subdirectories.