Gradle 4 for homebrew

gradle4.rb

# cat > /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core/Formula/gradle4.rb
# brew install --build-from-source gradle4
class Gradle4 < Formula
  desc "Open-source build automation tool based on the Groovy and Kotlin DSL"
  homepage "https://www.gradle.org/"
  url "https://services.gradle.org/distributions/gradle-4.10.3-all.zip"
  sha256 "336b6898b491f6334502d8074a6b8c2d73ed83b92123106bd4bf837f04111043"

  # not needed in newer gradle releases
  # bottle :unneeded

  def install
  rm_f Dir["bin/*.bat"]
    libexec.install %w[bin docs lib media samples src]
    (bin/"gradle").write_env_script libexec/"bin/gradle", Language::Java.overridable_java_home_env
  end

  def caveats
    <<~EOS
      This formula requires Java 8 to be installed, such as:
        brew install --cask adoptopenjdk8
    EOS
  end

  test do
    assert_match version.to_s, shell_output("#{bin}/gradle --version")
  end
end