brew install ./zsh-autosuggestions.rb --HEAD

zsh-autosuggestions.rb

require 'formula'

class ZshAutosuggestions < Formula
  homepage 'https://github.com/tarruda/zsh-autosuggestions'

  head 'https://github.com/tarruda/zsh-autosuggestions.git'

  def install
    (share/'zsh-autosuggestions').install Dir['*']
  end

  def caveats
    <<-EOS.undent

    Add the following at the end of your .zshrc:

      # Setup zsh-autosuggestions
      source #{HOMEBREW_PREFIX}/share/zsh-autosuggestions/autosuggestions.zsh

      # Enable autosuggestions automatically
      zle-line-init() {
              zle autosuggest-start
      }
      zle -N zle-line-init

    You will also need to force reload of your .zshrc:

      source ~/.zshrc

    EOS
  end
end