brew update is overzealous about linking tapped formula

[phinze]

After e613cbe the definition for where a Formula should be stored in a Tap was restricted to (1) root dir, (2) Formula dir, or (3) HomebrewFormula dir.

This works nicely, and in my project we exploit it to distribute a single formula in a Tap that also contains our Casks.

However, we've been fighting an issue (Homebrew/homebrew-cask#47) for awhile now where people are getting stray symlinks after running brew update. I think I may have found the culprit. The update Report is not being consistent about the policy I outlined above.

Have a look:

  def tapped_formula_for key
    fetch(key, []).map do |path|
      case path when %r{^Library/Taps/(\w+-\w+/.*)}
        Pathname.new($1)
      end
    end.compact
  end

https://github.com/mxcl/homebrew/blob/59c0b3f916c9a2bd141bc4a79199fa720c88f04f/Library/Homebrew/cmd/update.rb#L155-L161

That there is going to match any file in the directory that gets add it, and pass it up to:

https://github.com/mxcl/homebrew/blob/59c0b3f916c9a2bd141bc4a79199fa720c88f04f/Library/Homebrew/cmd/update.rb#L53

Which will happily link it.

Does it make sense to you folks that this should be scoped down to match the policy in the tap command? If so I can try for a PR.

Thanks for all the work you do! Homebrew is 🆒 😎 🍔 :)

[mistydemeo]

Report#tapped_formula_for should definitely be using the Pathname methods rather than reinventing the logic.

[phinze]

This landed last night, so we should be good to go. Thanks you guys are the best.