ocamlPackages.menhir: support --suggest-menhirLib (#358146)

{ buildDunePackage

{ buildDunePackage, substituteAll, ocaml

, menhirLib, menhirSdk

}:

  buildInputs = [ menhirLib menhirSdk ];

  patches = [

    (substituteAll {

      src = ./menhir-suggest-menhirLib.patch;

      libdir = "${menhirLib}/lib/ocaml/${ocaml.version}/site-lib/menhirLib";

    })

  ];

  meta = menhirSdk.meta // {

    description = "LR(1) parser generator for OCaml";

    mainProgram = "menhir";

diff --git a/src/installation.ml b/src/installation.ml

index 3c64e395..be7d6e7b 100644

--- a/src/installation.ml

+++ b/src/installation.ml

@@ -39,13 +39,4 @@ let rec normalize fn =

    and hope that it is of the form [.../bin/menhir]. We change this to

    [.../lib/menhirLib], and hope that this is where MenhirLib is installed. *)

-let libdir () =

-  let root =

-    Sys.executable_name

-    |> normalize

-    |> Filename.dirname (* remove [menhir] *)

-    |> Filename.dirname (* remove [bin] *)

-  in

-  Filename.concat

-    root

-    (Filename.concat "lib" "menhirLib")

+let libdir () = ignore normalize; "@libdir@"