coq 8.6

use opam to install ocamlfind temporarily

Closes #7874.

Signed-off-by: ilovezfs <ilovezfs@icloud.com>

Formula/coq.rb

@@ -13,10 +13,8 @@ end
 class Coq < Formula
   desc "Proof assistant for higher-order logic"
   homepage "https://coq.inria.fr/"
-  url "https://coq.inria.fr/distrib/8.5pl3/files/coq-8.5pl3.tar.gz"
-  version "8.5pl3"
-  sha256 "305b92e05d406d4d0c64f43d4fadb6b89419120a1d4ae4115ed1c5eb8812d33b"
-  revision 1
+  url "https://coq.inria.fr/distrib/V8.6/files/coq-8.6.tar.gz"
+  sha256 "6e3c3cf5c8e2b0b760dc52738e2e849f3a8c630869659ecc0cf41413fcee81df"
   head "git://scm.gforge.inria.fr/coq/coq.git", :branch => "trunk"
 
   bottle do
@@ -25,13 +23,21 @@ class Coq < Formula
     sha256 "17f5b15170776cebc527478b1b6247036682888fe2a270ab614febbd0f1b4326" => :yosemite
   end
 
+  depends_on "opam" => :build
   depends_on Camlp5TransitionalModeRequirement
   depends_on "camlp5"
   depends_on "ocaml"
 
   def install
+    ENV["OPAMYES"] = "1"
+    ENV["OPAMROOT"] = Pathname.pwd/"opamroot"
+    (Pathname.pwd/"opamroot").mkpath
+    system "opam", "init", "--no-setup"
+    system "opam", "install", "ocamlfind"
+
     camlp5_lib = Formula["camlp5"].opt_lib/"ocaml/camlp5"
-    system "./configure", "-prefix", prefix,
+    system "opam", "config", "exec", "--",
+           "./configure", "-prefix", prefix,
                           "-mandir", man,
                           "-camlp5dir", camlp5_lib,
                           "-emacslib", elisp,