Using Syntax.Verison.t to decide how to generate sub system files

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>

src/install_rules.ml

@@ -39,9 +39,11 @@ module Gen(P : Install_params) = struct
   let gen_lib_dune_file lib =
     SC.add_rule sctx
       (Build.arr (fun () ->
-         let lang = Option.value_exn (Lib.defined_using_lang lib) in
-         Format.asprintf "%a@." (Sexp.pp lang)
-           (Lib.Sub_system.dump_config lib |> Installed_dune_file.gen ~lang))
+         let dune_version = Option.value_exn (Lib.dune_version lib) in
+         Format.asprintf "%a@."
+           (Sexp.pp (Stanza.File_kind.of_syntax dune_version))
+           (Lib.Sub_system.dump_config lib
+            |> Installed_dune_file.gen ~dune_version))
        >>> Build.write_file_dyn
              (lib_dune_file ~dir:(Lib.src_dir lib) ~name:(Lib.name lib)))
 

src/installed_dune_file.ml

@@ -66,7 +66,7 @@ let load fname =
       (Univ_map.singleton (Syntax.key Stanza.syntax) syntax)
       (Io.Sexp.load ~lexer ~mode:Single fname))
 
-let gen ~(lang : File_tree.Dune_file.Kind.t) confs =
+let gen ~(dune_version : Syntax.Version.t) confs =
   let sexps =
     Sub_system_name.Map.to_list confs
     |> List.map ~f:(fun (name, (ver, conf)) ->
@@ -79,8 +79,11 @@ let gen ~(lang : File_tree.Dune_file.Kind.t) confs =
   Sexp.List
     [ Sexp.unsafe_atom_of_string "dune"
     ; Sexp.unsafe_atom_of_string
-        (match lang with
-         | Jbuild -> "1"
-         | Dune -> "2")
+        (match dune_version with
+         | (0, 0) -> "1"
+         | (1, 0) -> "2"
+         | _ ->
+           Exn.code_error "Cannot generate dune with unknown version"
+             ["dune_version", Syntax.Version.sexp_of_t dune_version])
     ; List sexps
     ]

src/installed_dune_file.mli

@@ -4,6 +4,6 @@ open Stdune
 
 val load : Path.t -> Jbuild.Sub_system_info.t Sub_system_name.Map.t
 val gen
-  : lang:File_tree.Dune_file.Kind.t
+  : dune_version:Syntax.Version.t
   -> (Syntax.Version.t * Sexp.t) Sub_system_name.Map.t
   -> Sexp.t

src/lib.ml

@@ -63,7 +63,7 @@ module Info = struct
     ; pps              : (Loc.t * Jbuild.Pp.t) list
     ; optional         : bool
     ; virtual_deps     : (Loc.t * string) list
-    ; defined_using_lang : File_tree.Dune_file.Kind.t option
+    ; dune_version : Syntax.Version.t option
     ; sub_systems      : Jbuild.Sub_system_info.t Sub_system_name.Map.t
     }
 
@@ -115,11 +115,7 @@ module Info = struct
     ; ppx_runtime_deps = conf.ppx_runtime_libraries
     ; pps = Jbuild.Preprocess_map.pps conf.buildable.preprocess
     ; sub_systems = conf.sub_systems
-    ; defined_using_lang =
-        Some
-          (match conf.project.kind with
-           | Dune -> Dune
-           | Jbuilder -> Jbuild)
+    ; dune_version = Some conf.dune_version
     }
 
   let of_findlib_package pkg =
@@ -149,7 +145,7 @@ module Info = struct
     ; (* We don't know how these are named for external libraries *)
       foreign_archives = Mode.Dict.make_both []
     ; sub_systems      = sub_systems
-    ; defined_using_lang = None
+    ; dune_version = None
     }
 end
 
@@ -244,7 +240,7 @@ type t =
   ; resolved_selects  : Resolved_select.t list
   ; optional          : bool
   ; user_written_deps : Jbuild.Lib_deps.t
-  ; defined_using_lang : File_tree.Dune_file.Kind.t option
+  ; dune_version : Syntax.Version.t option
   ; (* This is mutable to avoid this error:
 
        {[
@@ -351,7 +347,7 @@ let plugins      t = t.plugins
 let jsoo_runtime t = t.jsoo_runtime
 let unique_id    t = t.unique_id
 
-let defined_using_lang t = t.defined_using_lang
+let dune_version t = t.dune_version
 
 let src_dir t = t.src_dir
 let obj_dir t = t.obj_dir
@@ -672,7 +668,7 @@ let rec instantiate db name (info : Info.t) ~stack ~hidden =
     ; optional          = info.optional
     ; user_written_deps = Info.user_written_deps info
     ; sub_systems       = Sub_system_name.Map.empty
-    ; defined_using_lang = info.defined_using_lang
+    ; dune_version = info.dune_version
     }
   in
   t.sub_systems <-

src/lib.mli

@@ -26,7 +26,7 @@ val archives     : t -> Path.t list Mode.Dict.t
 val plugins      : t -> Path.t list Mode.Dict.t
 val jsoo_runtime : t -> Path.t list
 
-val defined_using_lang : t -> File_tree.Dune_file.Kind.t option
+val dune_version : t -> Syntax.Version.t option
 
 (** A unique integer identifier. It is only unique for the duration of
     the process *)
@@ -105,7 +105,7 @@ module Info : sig
     ; pps              : (Loc.t * Jbuild.Pp.t) list
     ; optional         : bool
     ; virtual_deps     : (Loc.t * string) list
-    ; defined_using_lang : File_tree.Dune_file.Kind.t option
+    ; dune_version : Syntax.Version.t option
     ; sub_systems      : Jbuild.Sub_system_info.t Sub_system_name.Map.t
     }
 

src/stanza.ml

@@ -13,7 +13,11 @@ let syntax =
     ]
 
 module File_kind = struct
-  type t = Jbuild | Dune
+  type t = Sexp.syntax = Jbuild | Dune
+
+  let of_syntax = function
+    | (0, 0) -> Jbuild
+    | (_, _) -> Dune
 end
 
 let file_kind () =

src/stanza.mli

@@ -18,7 +18,9 @@ end
 val syntax : Syntax.t
 
 module File_kind : sig
-  type t = Jbuild | Dune
+  type t = Sexp.syntax = Jbuild | Dune
+
+  val of_syntax : Syntax.Version.t -> t
 end
 
 (** Whether we are parsing a [jbuild] or [dune] file. *)