rust_nightly.rb

class RustNightly < Formula

  url "https://static.rust-lang.org/dist/rust-nightly-x86_64-apple-darwin.pkg", using: :nounzip
  homepage "http://www.rust-lang.org"
  sha1 ""

  version Date.today.to_s

  def install
    system "pkgutil --expand rust-nightly-x86_64-apple-darwin.pkg rn"
    mkdir "output"
    
    Dir.chdir "rn/rustc.pkg/Scripts/rustc" do
      lib_path_update("bin/rustc")
      lib_path_update("bin/rustdoc")
      lib_path_update("bin/rust-lldb")
    end
    cp_r Dir["rn/rustc.pkg/Scripts/rustc/*"], "output/"
    Dir.chdir "rn/cargo.pkg/Scripts/cargo" do
      lib_path_update("bin/cargo")
      rm "manifest.in"
    end
    cp_r Dir["rn/cargo.pkg/Scripts/cargo/*"], "output/"
    Dir.chdir "rn/rust-docs.pkg/Scripts/rust-docs" do
      rm "manifest.in"
    end
    cp_r Dir["rn/rust-docs.pkg/Scripts/rust-docs/*"], "output/"
    prefix.install Dir["output/*"]
  end

  private

  def otool(path)
    lines = %x[otool -L #{path}].split /\n/
    lines[1..-1].map do |line|
      line.
        strip.
        gsub(/ \(compatibility version.*$/, '')
    end
  end

  def install_name_tool(path, old)
    pattern = 'x86_64-apple-darwin/stage1/lib/rustlib/x86_64-apple-darwin'
    if path.match(pattern)
      new = old.gsub(pattern, prefix)
      system("install_name_tool -change '#{old}' '#{new}' '#{path}'")
    end
  end

  def lib_path_update(binary)
    otool(binary).each do |current_lib_path|
      install_name_tool(binary, current_lib_path)
    end
  end

end