libedit: import homebrew/dupes into core.

Formula/libedit.rb

@@ -0,0 +1,37 @@
+class Libedit < Formula
+  desc "BSD-style licensed readline alternative"
+  homepage "http://thrysoee.dk/editline/"
+  url "http://thrysoee.dk/editline/libedit-20160903-3.1.tar.gz"
+  version "20160903-3.1"
+  sha256 "0ccbd2e7d46097f136fcb1aaa0d5bc24e23bb73f57d25bee5a852a683eaa7567"
+
+  bottle do
+    cellar :any
+    sha256 "aa5bebaa567a011aec09ae73ebac1a41c10b1281bcbda8db6b34856c0ad72fa5" => :sierra
+    sha256 "c59f6ef3c9fa7a3936dbd26c8d46c2d99120b320f59716cfa89c8dbd9bf7db66" => :el_capitan
+    sha256 "5fb64cf9e71fe11c38bb6f1c69c3254a93bfa78300601904193e8f746809cbfb" => :yosemite
+  end
+
+  keg_only :provided_by_osx
+
+  def install
+    system "./configure", "--disable-dependency-tracking",
+                          "--disable-silent-rules",
+                          "--enable-widec",
+                          "--prefix=#{prefix}"
+    system "make", "install"
+  end
+
+  test do
+    (testpath/"test.c").write <<-EOS.undent
+      #include <stdio.h>
+      #include <histedit.h>
+      int main(int argc, char *argv[]) {
+        EditLine *el = el_init(argv[0], stdin, stdout, stderr);
+        return (el == NULL);
+      }
+    EOS
+    system ENV.cc, "test.c", "-o", "test", "-L#{lib}", "-ledit", "-I#{include}"
+    system "./test"
+  end
+end