RWTH USGerman Keyboard Layout via Homebrew

install.sh

brew create "https://hci.rwth-aachen.de/get-attachment/2764?fallback=/files/migrated/files/USGerman-Keyboard-Layout-0.98-Retina.zip&filename=USGerman%20Keyboard%20Layout%200.98%20Retina.zip" --set-name usgerman-keyboard-layout
brew uninstall usgerman-keyboard-layout
brew install --build-from-source /opt/homebrew/Library/Taps/homebrew/homebrew-core/Formula/u/usgerman-keyboard-layout.rb

usgerman-keyboard-layout.rb

# Documentation: https://docs.brew.sh/Formula-Cookbook
#                https://rubydoc.brew.sh/Formula
# PLEASE REMOVE ALL GENERATED COMMENTS BEFORE SUBMITTING YOUR PULL REQUEST!
class UsgermanKeyboardLayout < Formula
  desc "USGerman Keyboard Layout for macOS"
  homepage "https://hci.rwth-aachen.de/usgermankeyboard"
  url "https://hci.rwth-aachen.de/get-attachment/2764?fallback=/files/migrated/files/USGerman-Keyboard-Layout-0.98-Retina.zip&filename=USGerman%20Keyboard%20Layout%200.98%20Retina.zip"
  sha256 "3d6f420185a7b104da45411c0a380d342606d3b20281984b30cac59fbae8fb39"
  version "0.98"

  def install
    # TISInputSourceID and TISIntendedLanguage are required for macOS 14.2 and later
    system "/usr/libexec/PlistBuddy", "-c", "Add :TISInputSourceID string com.apple.keyboardlayout.roman.roman", "Roman.bundle/Contents/Info.plist"
    system "/usr/libexec/PlistBuddy", "-c", "Add :TISIntendedLanguage string en-US", "Roman.bundle/Contents/Info.plist"

    prefix.install "Roman.bundle"
    
    (prefix/"postinstall.sh").write <<~EOS
      #!/bin/bash
      sudo cp -R #{prefix}/Roman.bundle /Library/Keyboard\\ Layouts/
    EOS

    chmod 0755, prefix/"postinstall.sh"

    ohai "You NEED to run '#{prefix}/postinstall.sh' to install the keyboard system-wide."
  end

  def caveats
    <<~EOS
      The USGerman Keyboard Layout has been installed.
      You may need to log out and back in again or restart your system to activate the new layout.
      Then go to System Settings > Keyboard > Text Input > Input Sources > + > Others > U.S. With Umlauts via Option Key to add the new layout.
    EOS
  end
  
  test do
    assert_predicate "/Library/Keyboard Layouts/Roman.bundle", :exist?
  end
end