ocamlPackages.rope: refactor

- remove legacy version 0.5 (broken)
 - disable for OCaml ≥ 5.0

pkgs/development/ocaml-modules/rope/default.nix

@@ -1,45 +1,24 @@
-{ stdenv, lib, fetchurl, ocaml, findlib, ocamlbuild, dune_2, benchmark }:
+{ lib, fetchurl, ocaml, buildDunePackage, benchmark }:
 
-let param =
-  if lib.versionAtLeast ocaml.version "4.03"
-  then rec {
-    version = "0.6.2";
-    url = "https://github.com/Chris00/ocaml-rope/releases/download/${version}/rope-${version}.tbz";
-    sha256 = "15cvfa0s1vjx7gjd07d3fkznilishqf4z4h2q5f20wm9ysjh2h2i";
-    nativeBuildInputs = [ dune_2 ];
-    extra = {
-      buildPhase = "dune build -p rope";
-      installPhase = ''
-        dune install --prefix $out --libdir $OCAMLFIND_DESTDIR rope
-      '';
-    };
-  } else {
-    version = "0.5";
-    url = "https://forge.ocamlcore.org/frs/download.php/1156/rope-0.5.tar.gz";
-    sha256 = "05fr2f5ch2rqhyaj06rv5218sbg99p1m9pq5sklk04hpslxig21f";
-    nativeBuildInputs = [ ocamlbuild ];
-    extra = { createFindlibDestdir = true; };
-  };
-in
+lib.throwIf (lib.versionAtLeast ocaml.version "5.0")
+  "rope is not available for OCaml ${ocaml.version}"
 
-stdenv.mkDerivation ({
-  pname = "ocaml${ocaml.version}-rope";
-  inherit (param) version;
+buildDunePackage rec {
+  pname = "rope";
+  version = "0.6.2";
+  minimalOCamlVersion = "4.03";
 
   src = fetchurl {
-    inherit (param) url sha256;
+    url = "https://github.com/Chris00/ocaml-rope/releases/download/${version}/rope-${version}.tbz";
+    sha256 = "15cvfa0s1vjx7gjd07d3fkznilishqf4z4h2q5f20wm9ysjh2h2i";
   };
 
-  nativeBuildInputs = [ ocaml findlib ] ++ param.nativeBuildInputs;
   buildInputs = [ benchmark ] ;
 
-  strictDeps = true;
-
   meta = {
-    homepage = "http://rope.forge.ocamlcore.org/";
-    inherit (ocaml.meta) platforms;
-    description = ''Ropes ("heavyweight strings") in OCaml'';
+    homepage = "https://github.com/Chris00/ocaml-rope";
+    description = "Ropes (“heavyweight strings”) in OCaml";
     license = lib.licenses.lgpl21;
     maintainers = with lib.maintainers; [ ];
   };
-} // param.extra)
+}