A slight tweak to sra's xplot formula for homebrew

xplot.rb

# Based on https://git.hactrn.net/sra/Homebrew-Tap/raw/master/xplot.rb
# Updated by dre for macOS 11.5.3
#   - prepended `autoconf` and `autoupdate`, which are really living up
#     to their names. The *newest* part of xplot is from 1996.

# Documentation: https://docs.brew.sh/Formula-Cookbook
#                http://www.rubydoc.info/github/Homebrew/brew/master/Formula
class Xplot < Formula
  desc "xplot"
  homepage "http://www.xplot.org"
  url "http://www.xplot.org/xplot/xplot-0.90.7.1.tar.gz"
  sha256 "01ceac45540f2d01e6ffe368cc0e950f4bb7fe1d235efde5349a09199e662240"
  depends_on "cmake" => :build
  depends_on "autoconf" => :build

  def install
    system "autoconf ; autoupdate"
    system "./configure", "--disable-debug",
                          "--disable-silent-rules",
                          "--x-includes=/opt/X11/include",
                          "--x-libraries=/opt/X11/lib",
                          "--prefix=#{prefix}"
    system "make", "install" # if this fails, try separate make/make install steps
  end
end