From 67edb7f89e0fd6d108649b32a2a3c8d2d186d97c Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 15:19:54 +0700
Subject: [PATCH 01/19] Move make_loc to Loc module and rename it to of_lexbuf

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/usexp/loc.ml   |  5 +++++
 src/usexp/loc.mli  |  2 ++
 src/usexp/usexp.ml | 19 +++++++------------
 3 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/src/usexp/loc.ml b/src/usexp/loc.ml
index d7ac4844..54c9aeac 100644
--- a/src/usexp/loc.ml
+++ b/src/usexp/loc.ml
@@ -16,3 +16,8 @@ let in_file fn =
   }
 
 let none = in_file "<none>"
+
+let of_lexbuf lexbuf : t =
+  { start = Lexing.lexeme_start_p lexbuf
+  ; stop  = Lexing.lexeme_end_p   lexbuf
+  }
diff --git a/src/usexp/loc.mli b/src/usexp/loc.mli
index 514f3a68..2526948e 100644
--- a/src/usexp/loc.mli
+++ b/src/usexp/loc.mli
@@ -6,3 +6,5 @@ type t =
 val in_file : string -> t
 
 val none : t
+
+val of_lexbuf : Lexing.lexbuf -> t
diff --git a/src/usexp/usexp.ml b/src/usexp/usexp.ml
index 3681098a..b687686e 100644
--- a/src/usexp/usexp.ml
+++ b/src/usexp/usexp.ml
@@ -166,11 +166,6 @@ module Parser = struct
              ; message
              })
 
-  let make_loc lexbuf : Loc.t =
-    { start = Lexing.lexeme_start_p lexbuf
-    ; stop  = Lexing.lexeme_end_p   lexbuf
-    }
-
   module Mode = struct
     type 'a t =
       | Single      : Ast.t t
@@ -183,7 +178,7 @@ module Parser = struct
         | Single -> begin
           match sexps with
           | [sexp] -> sexp
-          | [] -> error (make_loc lexbuf) "no s-expression found in input"
+          | [] -> error (Loc.of_lexbuf lexbuf) "no s-expression found in input"
           | _ :: sexp :: _ ->
             error (Ast.loc sexp) "too many s-expressions found in input"
         end
@@ -200,13 +195,13 @@ module Parser = struct
   let rec loop depth lexer lexbuf acc =
     match (lexer lexbuf : Lexer.Token.t) with
     | Atom a ->
-      let loc = make_loc lexbuf in
+      let loc = Loc.of_lexbuf lexbuf in
       loop depth lexer lexbuf (Ast.Atom (loc, a) :: acc)
     | Quoted_string s ->
-      let loc = make_loc lexbuf in
+      let loc = Loc.of_lexbuf lexbuf in
       loop depth lexer lexbuf (Quoted_string (loc, s) :: acc)
     | Template t ->
-      let loc = make_loc lexbuf in
+      let loc = Loc.of_lexbuf lexbuf in
       loop depth lexer lexbuf (Template { t with loc } :: acc)
     | Lparen ->
       let start = Lexing.lexeme_start_p lexbuf in
@@ -215,12 +210,12 @@ module Parser = struct
       loop depth lexer lexbuf (List ({ start; stop }, sexps) :: acc)
     | Rparen ->
       if depth = 0 then
-        error (make_loc lexbuf)
+        error (Loc.of_lexbuf lexbuf)
           "right parenthesis without matching left parenthesis";
       List.rev acc
     | Sexp_comment ->
       let sexps =
-        let loc = make_loc lexbuf in
+        let loc = Loc.of_lexbuf lexbuf in
         match loop depth lexer lexbuf [] with
         | _ :: sexps -> sexps
         | [] -> error loc "s-expression missing after #;"
@@ -228,7 +223,7 @@ module Parser = struct
       List.rev_append acc sexps
     | Eof ->
       if depth > 0 then
-        error (make_loc lexbuf)
+        error (Loc.of_lexbuf lexbuf)
           "unclosed parenthesis at end of input";
       List.rev acc
 

From 179d23ee3872b792e1db6af4a13612622909be35 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 15:20:12 +0700
Subject: [PATCH 02/19] Expose the type of tokens and lexers

This will be necessary for some manual parsing

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/usexp/usexp.mli | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/src/usexp/usexp.mli b/src/usexp/usexp.mli
index f6c55388..bc0ad768 100644
--- a/src/usexp/usexp.mli
+++ b/src/usexp/usexp.mli
@@ -28,6 +28,8 @@ module Loc : sig
   val in_file : string -> t
 
   val none : t
+
+  val of_lexbuf : Lexing.lexbuf -> t
 end
 
 module Template : sig
@@ -112,7 +114,18 @@ end
 exception Parse_error of Parse_error.t
 
 module Lexer : sig
-  type t
+  module Token : sig
+    type t =
+      | Atom          of Atom.t
+      | Quoted_string of string
+      | Lparen
+      | Rparen
+      | Sexp_comment
+      | Eof
+      | Template of Template.t
+  end
+
+  type t = Lexing.lexbuf -> Token.t
 
   val token : t
   val jbuild_token : t

From c906801c69654a247d690d5aee0c6ed9177666ee Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 15:20:40 +0700
Subject: [PATCH 03/19] Parse dune files in a versioned way.

We read the first 3 tokens of a dune file and use it recognize if the file was
generated using jbuilder or dune

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index ab7535cc..3fc1d3c2 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -45,7 +45,36 @@ let of_sexp =
     ]
 
 let load fname =
-  Sexp.Of_sexp.parse of_sexp Univ_map.empty (Io.Sexp.load ~mode:Single fname)
+  Io.with_lexbuf_from_file fname ~f:(fun lexbuf ->
+    let (version_loc, version) =
+      let bad_dune_file = "Unable to read (dune x.y ..) line file" in
+      let rec loop = function
+        | [_; _; _] as a -> List.rev a
+        | acc ->
+          begin match (Sexp.Lexer.token lexbuf : Sexp.Lexer.Token.t) with
+          | Eof ->
+            Loc.fail (Loc.in_file (Path.to_string fname)) "%s" bad_dune_file
+          | t -> loop (t :: acc)
+          end
+      in
+      match loop [] with
+      | [Lparen; Atom (A "dune"); Atom s] ->
+        (Sexp.Loc.of_lexbuf lexbuf, Sexp.Atom.to_string s)
+      | _ ->
+        Loc.fail
+          { start = Lexing.lexeme_start_p lexbuf
+          ; stop = Lexing.lexeme_end_p lexbuf
+          } "%s" bad_dune_file
+    in
+    match version with
+    | "1" ->
+      Sexp.Of_sexp.parse of_sexp Univ_map.empty
+        (Io.Sexp.load ~lexer:Sexp.Lexer.jbuild_token ~mode:Single fname)
+    | "2" ->
+      Sexp.Of_sexp.parse of_sexp Univ_map.empty
+        (Io.Sexp.load ~lexer:Sexp.Lexer.token ~mode:Single fname)
+    | _ ->
+      Loc.fail version_loc "unknown version %S" version)
 
 let gen confs =
   let sexps =

From a4bc2602410c1dfa8516b89ab9a6975d2b6c3575 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 16:56:19 +0700
Subject: [PATCH 04/19] Loc.of_lexbuf

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 3fc1d3c2..1940b5ed 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -61,10 +61,7 @@ let load fname =
       | [Lparen; Atom (A "dune"); Atom s] ->
         (Sexp.Loc.of_lexbuf lexbuf, Sexp.Atom.to_string s)
       | _ ->
-        Loc.fail
-          { start = Lexing.lexeme_start_p lexbuf
-          ; stop = Lexing.lexeme_end_p lexbuf
-          } "%s" bad_dune_file
+        Loc.fail (Sexp.Loc.of_lexbuf lexbuf) "%s" bad_dune_file
     in
     match version with
     | "1" ->

From 8390af90e4018bd479ccc5228689d109499daf96 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 17:00:02 +0700
Subject: [PATCH 05/19] Simplify versioning matching

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 1940b5ed..8c9b98e7 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -63,15 +63,13 @@ let load fname =
       | _ ->
         Loc.fail (Sexp.Loc.of_lexbuf lexbuf) "%s" bad_dune_file
     in
-    match version with
-    | "1" ->
-      Sexp.Of_sexp.parse of_sexp Univ_map.empty
-        (Io.Sexp.load ~lexer:Sexp.Lexer.jbuild_token ~mode:Single fname)
-    | "2" ->
-      Sexp.Of_sexp.parse of_sexp Univ_map.empty
-        (Io.Sexp.load ~lexer:Sexp.Lexer.token ~mode:Single fname)
-    | _ ->
-      Loc.fail version_loc "unknown version %S" version)
+    let lexer =
+      match version with
+      | "1" -> Sexp.Lexer.jbuild_token
+      | "2" -> Sexp.Lexer.token
+      | _   -> Loc.fail version_loc "unknown version %S" version
+    in
+    Sexp.Of_sexp.parse of_sexp Univ_map.empty lexer ~mode:Single fname
 
 let gen confs =
   let sexps =

From bedad1f6898da158054d687ca84b3ef8fa608fa8 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 17:08:15 +0700
Subject: [PATCH 06/19] Set version when parsing dune files

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 8c9b98e7..a1afb4a6 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -63,13 +63,15 @@ let load fname =
       | _ ->
         Loc.fail (Sexp.Loc.of_lexbuf lexbuf) "%s" bad_dune_file
     in
-    let lexer =
+    let (lexer, syntax) =
       match version with
-      | "1" -> Sexp.Lexer.jbuild_token
-      | "2" -> Sexp.Lexer.token
+      | "1" -> (Sexp.Lexer.jbuild_token, (0, 0))
+      | "2" -> (Sexp.Lexer.token, (1, 0))
       | _   -> Loc.fail version_loc "unknown version %S" version
     in
-    Sexp.Of_sexp.parse of_sexp Univ_map.empty lexer ~mode:Single fname
+    Sexp.Of_sexp.parse of_sexp
+      (Univ_map.singleton (Syntax.key Stanza.syntax) syntax)
+      (Io.Sexp.load ~lexer ~mode:Single fname))
 
 let gen confs =
   let sexps =

From 7b12e12571f344a93e731c236a826a6d65a7e0ca Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 17:09:27 +0700
Subject: [PATCH 07/19] Share loc variable

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index a1afb4a6..803a4918 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -57,11 +57,10 @@ let load fname =
           | t -> loop (t :: acc)
           end
       in
+      let loc = Sexp.Loc.of_lexbuf lexbuf in
       match loop [] with
-      | [Lparen; Atom (A "dune"); Atom s] ->
-        (Sexp.Loc.of_lexbuf lexbuf, Sexp.Atom.to_string s)
-      | _ ->
-        Loc.fail (Sexp.Loc.of_lexbuf lexbuf) "%s" bad_dune_file
+      | [Lparen; Atom (A "dune"); Atom s] -> (loc, Sexp.Atom.to_string s)
+      | _ -> Loc.fail loc "%s" bad_dune_file
     in
     let (lexer, syntax) =
       match version with

From ba9335badf0f43f9c788571221d798ad69c5e443 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 17:32:05 +0700
Subject: [PATCH 08/19] Simplify dump_config with Option.map

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/lib.ml | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/lib.ml b/src/lib.ml
index 71f584d6..5a2a3920 100644
--- a/src/lib.ml
+++ b/src/lib.ml
@@ -508,9 +508,7 @@ module Sub_system = struct
   let dump_config lib =
     Sub_system_name.Map.filter_map lib.sub_systems ~f:(fun (lazy inst) ->
       let (Sub_system0.Instance.T ((module M), t)) = inst in
-      match M.to_sexp with
-      | None -> None
-      | Some f -> Some (f t))
+      Option.map ~f:(fun f -> f t) M.to_sexp)
 end
 
 (* +-----------------------------------------------------------------+

From 9c0daa24defa2e488b60d84530b42f420b6182f0 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 23:00:17 +0700
Subject: [PATCH 09/19] Don't hard code parsing_context for sub systems

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 803a4918..422f20fc 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -1,6 +1,6 @@
 open Import
 
-let parse_sub_systems sexps =
+let parse_sub_systems ~parsing_context sexps =
   List.filter_map sexps ~f:(fun sexp ->
     let name, ver, data =
       Sexp.Of_sexp.(parse (triple string (located Syntax.Version.t) raw)
@@ -21,11 +21,6 @@ let parse_sub_systems sexps =
   |> Sub_system_name.Map.mapi ~f:(fun name (_, version, data) ->
     let (module M) = Jbuild.Sub_system_info.get name in
     Syntax.check_supported M.syntax version;
-    let parsing_context =
-      Univ_map.singleton (Syntax.key M.syntax)
-        (* This is wrong, see #909 *)
-        (0, 0)
-    in
     M.T (Sexp.Of_sexp.parse M.parse parsing_context data))
 
 let of_sexp =
@@ -40,8 +35,9 @@ let of_sexp =
   sum
     [ "dune",
       (version >>= fun () ->
-       list raw >>| fun l ->
-       parse_sub_systems l)
+       get_all >>= fun parsing_context ->
+       list raw >>|
+       parse_sub_systems ~parsing_context)
     ]
 
 let load fname =

From f6fe5d20bbe4d6c9c008433ffb2c8065e4917279 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Sun, 1 Jul 2018 23:18:36 +0700
Subject: [PATCH 10/19] Generate dune file version correctly

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/install_rules.ml                              |  3 ++-
 src/installed_dune_file.ml                        | 13 ++++++++-----
 src/installed_dune_file.mli                       |  5 ++++-
 src/lib.ml                                        | 11 +++++++++++
 src/lib.mli                                       |  3 +++
 test/blackbox-tests/test-cases/inline_tests/run.t |  2 +-
 6 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/src/install_rules.ml b/src/install_rules.ml
index 3c679e40..6b8b763d 100644
--- a/src/install_rules.ml
+++ b/src/install_rules.ml
@@ -39,8 +39,9 @@ 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 Dune)
-           (Lib.Sub_system.dump_config lib |> Installed_dune_file.gen))
+           (Lib.Sub_system.dump_config lib |> Installed_dune_file.gen ~lang))
        >>> Build.write_file_dyn
              (lib_dune_file ~dir:(Lib.src_dir lib) ~name:(Lib.name lib)))
 
diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 422f20fc..b3abe8d6 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -27,10 +27,10 @@ let of_sexp =
   let open Sexp.Of_sexp in
   let version =
     plain_string (fun ~loc -> function
-      | "1" -> ()
-      | _ ->
+      | "1" | "2" -> ()
+      | v ->
         of_sexp_errorf loc
-          "Unsupported version, only version 1 is supported")
+          "Unsupported version %S, only version 1 is supported" v)
   in
   sum
     [ "dune",
@@ -68,7 +68,7 @@ let load fname =
       (Univ_map.singleton (Syntax.key Stanza.syntax) syntax)
       (Io.Sexp.load ~lexer ~mode:Single fname))
 
-let gen confs =
+let gen ~(lang : File_tree.Dune_file.Kind.t) confs =
   let sexps =
     Sub_system_name.Map.to_list confs
     |> List.map ~f:(fun (name, (ver, conf)) ->
@@ -80,6 +80,9 @@ let gen confs =
   in
   Sexp.List
     [ Sexp.unsafe_atom_of_string "dune"
-    ; Sexp.unsafe_atom_of_string "1"
+    ; Sexp.unsafe_atom_of_string
+        (match lang with
+         | Jbuild -> "1"
+         | Dune -> "2")
     ; List sexps
     ]
diff --git a/src/installed_dune_file.mli b/src/installed_dune_file.mli
index d498cb00..019e5c88 100644
--- a/src/installed_dune_file.mli
+++ b/src/installed_dune_file.mli
@@ -3,4 +3,7 @@
 open Stdune
 
 val load : Path.t -> Jbuild.Sub_system_info.t Sub_system_name.Map.t
-val gen : (Syntax.Version.t * Sexp.t) Sub_system_name.Map.t -> Sexp.t
+val gen
+  : lang:File_tree.Dune_file.Kind.t
+  -> (Syntax.Version.t * Sexp.t) Sub_system_name.Map.t
+  -> Sexp.t
diff --git a/src/lib.ml b/src/lib.ml
index 5a2a3920..4635a120 100644
--- a/src/lib.ml
+++ b/src/lib.ml
@@ -63,6 +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
     ; sub_systems      : Jbuild.Sub_system_info.t Sub_system_name.Map.t
     }
 
@@ -114,6 +115,11 @@ 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)
     }
 
   let of_findlib_package pkg =
@@ -143,6 +149,7 @@ 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
     }
 end
 
@@ -237,6 +244,7 @@ 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
   ; (* This is mutable to avoid this error:
 
        {[
@@ -343,6 +351,8 @@ 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 src_dir t = t.src_dir
 let obj_dir t = t.obj_dir
 
@@ -662,6 +672,7 @@ 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
     }
   in
   t.sub_systems <-
diff --git a/src/lib.mli b/src/lib.mli
index d70ef8c9..795727fb 100644
--- a/src/lib.mli
+++ b/src/lib.mli
@@ -26,6 +26,8 @@ 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
+
 (** A unique integer identifier. It is only unique for the duration of
     the process *)
 val unique_id : t -> int
@@ -103,6 +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
     ; sub_systems      : Jbuild.Sub_system_info.t Sub_system_name.Map.t
     }
 
diff --git a/test/blackbox-tests/test-cases/inline_tests/run.t b/test/blackbox-tests/test-cases/inline_tests/run.t
index 3646e4ae..d46693c7 100644
--- a/test/blackbox-tests/test-cases/inline_tests/run.t
+++ b/test/blackbox-tests/test-cases/inline_tests/run.t
@@ -22,7 +22,7 @@
 
   $ dune runtest dune-file
   (dune
-   1
+   2
    ((inline_tests.backend
      1.0
      ((runner_libraries (str))

From 01163776ad3b5e2c20e9a6c9c5963b90d38dd121 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 13:09:10 +0700
Subject: [PATCH 11/19] s/Dune/lang/

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/install_rules.ml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/install_rules.ml b/src/install_rules.ml
index 6b8b763d..fb87fb98 100644
--- a/src/install_rules.ml
+++ b/src/install_rules.ml
@@ -40,7 +40,7 @@ module Gen(P : Install_params) = struct
     SC.add_rule sctx
       (Build.arr (fun () ->
          let lang = Option.value_exn (Lib.defined_using_lang lib) in
-         Format.asprintf "%a@." (Sexp.pp Dune)
+         Format.asprintf "%a@." (Sexp.pp lang)
            (Lib.Sub_system.dump_config lib |> Installed_dune_file.gen ~lang))
        >>> Build.write_file_dyn
              (lib_dune_file ~dir:(Lib.src_dir lib) ~name:(Lib.name lib)))

From 9005ca899862b2c91ea627426772dedaa83d7f74 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 13:34:14 +0700
Subject: [PATCH 12/19] Simplify error handling

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index b3abe8d6..45ace65f 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -43,20 +43,18 @@ let of_sexp =
 let load fname =
   Io.with_lexbuf_from_file fname ~f:(fun lexbuf ->
     let (version_loc, version) =
-      let bad_dune_file = "Unable to read (dune x.y ..) line file" in
       let rec loop = function
         | [_; _; _] as a -> List.rev a
         | acc ->
           begin match (Sexp.Lexer.token lexbuf : Sexp.Lexer.Token.t) with
-          | Eof ->
-            Loc.fail (Loc.in_file (Path.to_string fname)) "%s" bad_dune_file
+          | Eof -> List.rev acc
           | t -> loop (t :: acc)
           end
       in
       let loc = Sexp.Loc.of_lexbuf lexbuf in
       match loop [] with
       | [Lparen; Atom (A "dune"); Atom s] -> (loc, Sexp.Atom.to_string s)
-      | _ -> Loc.fail loc "%s" bad_dune_file
+      | _ -> Loc.fail loc "Unable to read (dune x.y ..) line file"
     in
     let (lexer, syntax) =
       match version with

From 22cf958b0c74edb9694730f827e5dfe0a9cb373e Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 14:08:28 +0700
Subject: [PATCH 13/19] Add dune_version field for libraries

This field is necessary to know how to generate .dune files for a particular
library.

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/jbuild.ml  | 3 +++
 src/jbuild.mli | 1 +
 2 files changed, 4 insertions(+)

diff --git a/src/jbuild.ml b/src/jbuild.ml
index 7b460de3..d6d8ef63 100644
--- a/src/jbuild.ml
+++ b/src/jbuild.ml
@@ -732,6 +732,7 @@ module Library = struct
     ; project                  : Dune_project.t
     ; sub_systems              : Sub_system_info.t Sub_system_name.Map.t
     ; no_keep_locs             : bool
+    ; dune_version             : Syntax.Version.t
     }
 
   let t =
@@ -763,6 +764,7 @@ module Library = struct
        field_b "no_keep_locs" >>= fun no_keep_locs ->
        Sub_system_info.record_parser () >>= fun sub_systems ->
        Dune_project.get_exn () >>= fun project ->
+       Syntax.get_exn Stanza.syntax >>= fun dune_version ->
        return
          { name
          ; public
@@ -786,6 +788,7 @@ module Library = struct
          ; project
          ; sub_systems
          ; no_keep_locs
+         ; dune_version
          })
 
   let has_stubs t =
diff --git a/src/jbuild.mli b/src/jbuild.mli
index e9048140..82174b7a 100644
--- a/src/jbuild.mli
+++ b/src/jbuild.mli
@@ -206,6 +206,7 @@ module Library : sig
     ; project                  : Dune_project.t
     ; sub_systems              : Sub_system_info.t Sub_system_name.Map.t
     ; no_keep_locs             : bool
+    ; dune_version             : Syntax.Version.t
     }
 
   val has_stubs : t -> bool

From 4af1f189f036d2650ce07363169a3dc5e0d439fe Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 14:23:13 +0700
Subject: [PATCH 14/19] 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        |  8 +++++---
 src/installed_dune_file.ml  | 11 +++++++----
 src/installed_dune_file.mli |  2 +-
 src/lib.ml                  | 16 ++++++----------
 src/lib.mli                 |  4 ++--
 src/stanza.ml               |  6 +++++-
 src/stanza.mli              |  4 +++-
 7 files changed, 29 insertions(+), 22 deletions(-)

diff --git a/src/install_rules.ml b/src/install_rules.ml
index fb87fb98..75729b6c 100644
--- a/src/install_rules.ml
+++ b/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)))
 
diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 45ace65f..8e5ee1c9 100644
--- a/src/installed_dune_file.ml
+++ b/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
     ]
diff --git a/src/installed_dune_file.mli b/src/installed_dune_file.mli
index 019e5c88..a82abb8e 100644
--- a/src/installed_dune_file.mli
+++ b/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
diff --git a/src/lib.ml b/src/lib.ml
index 4635a120..d11f8f67 100644
--- a/src/lib.ml
+++ b/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 <-
diff --git a/src/lib.mli b/src/lib.mli
index 795727fb..b50a4a7c 100644
--- a/src/lib.mli
+++ b/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
     }
 
diff --git a/src/stanza.ml b/src/stanza.ml
index b6166c8f..898257f2 100644
--- a/src/stanza.ml
+++ b/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 () =
diff --git a/src/stanza.mli b/src/stanza.mli
index 5377360b..1934f06b 100644
--- a/src/stanza.mli
+++ b/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. *)

From 0051aeca291e028a2e9dceefcc6a766719c7297c Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 14:42:43 +0700
Subject: [PATCH 15/19] Do not read .dune files twice

Reuse the same lexer by pushing back some tokens manually

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 8e5ee1c9..089b108e 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -42,7 +42,7 @@ let of_sexp =
 
 let load fname =
   Io.with_lexbuf_from_file fname ~f:(fun lexbuf ->
-    let (version_loc, version) =
+    let (tokens, version_loc, version) =
       let rec loop = function
         | [_; _; _] as a -> List.rev a
         | acc ->
@@ -53,7 +53,8 @@ let load fname =
       in
       let loc = Sexp.Loc.of_lexbuf lexbuf in
       match loop [] with
-      | [Lparen; Atom (A "dune"); Atom s] -> (loc, Sexp.Atom.to_string s)
+      | [Lparen; Atom (A "dune"); Atom s] as tokens ->
+        (tokens, loc, Sexp.Atom.to_string s)
       | _ -> Loc.fail loc "Unable to read (dune x.y ..) line file"
     in
     let (lexer, syntax) =
@@ -62,9 +63,17 @@ let load fname =
       | "2" -> (Sexp.Lexer.token, (1, 0))
       | _   -> Loc.fail version_loc "unknown version %S" version
     in
+    (* push back the tokens that we already read *)
+    let lexer =
+      let pending_tokens = ref tokens in
+      fun lb ->
+        match !pending_tokens with
+        | [] -> lexer lb
+        | x :: xs -> pending_tokens := xs; x
+    in
     Sexp.Of_sexp.parse of_sexp
       (Univ_map.singleton (Syntax.key Stanza.syntax) syntax)
-      (Io.Sexp.load ~lexer ~mode:Single fname))
+      (Sexp.Parser.parse ~lexer ~mode:Single lexbuf))
 
 let gen ~(dune_version : Syntax.Version.t) confs =
   let sexps =

From 044c78281d850bd7f654923da8ca10f7244cb276 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 15:05:15 +0700
Subject: [PATCH 16/19] Use parsing context when parsing name, version, raw
 triple of sub systems

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 089b108e..ad7fbf9a 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -4,7 +4,7 @@ let parse_sub_systems ~parsing_context sexps =
   List.filter_map sexps ~f:(fun sexp ->
     let name, ver, data =
       Sexp.Of_sexp.(parse (triple string (located Syntax.Version.t) raw)
-                      Univ_map.empty) sexp
+                      parsing_context) sexp
     in
     match Sub_system_name.get name with
     | None ->

From 04ee6b0b2d683a202fc79fa1d3b2dddcf5d389d4 Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Mon, 2 Jul 2018 16:33:12 +0700
Subject: [PATCH 17/19] Set M.syntax when reading subsystems generated by dune

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index ad7fbf9a..5e1c0476 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -21,6 +21,17 @@ let parse_sub_systems ~parsing_context sexps =
   |> Sub_system_name.Map.mapi ~f:(fun name (_, version, data) ->
     let (module M) = Jbuild.Sub_system_info.get name in
     Syntax.check_supported M.syntax version;
+    let parsing_context =
+      (* We set the syntax to the version used when generating this subsystem.
+         We cannot do this for jbuild defined subsystems however since those use
+         1.0 as the version. Which would correspond to the dune syntax (because
+         subsystems share the syntax of the dune lang) *)
+      match Univ_map.find_exn parsing_context (Syntax.key Stanza.syntax) with
+      | (0, 0) ->
+        parsing_context
+      | (_, _) ->
+        Univ_map.add parsing_context (Syntax.key M.syntax) (snd version)
+    in
     M.T (Sexp.Of_sexp.parse M.parse parsing_context data))
 
 let of_sexp =

From 6589464f216af43bb64f844ee76a944e93d92fcd Mon Sep 17 00:00:00 2001
From: Jeremie Dimino <jeremie@dimino.org>
Date: Tue, 3 Jul 2018 09:22:57 +0100
Subject: [PATCH 18/19] Rewrite lexing of installed dune files

Signed-off-by: Jeremie Dimino <jeremie@dimino.org>
---
 src/installed_dune_file.ml | 68 ++++++++++++++++++--------------------
 1 file changed, 33 insertions(+), 35 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 5e1c0476..0102555e 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -38,52 +38,50 @@ let of_sexp =
   let open Sexp.Of_sexp in
   let version =
     plain_string (fun ~loc -> function
-      | "1" | "2" -> ()
+      | "1" -> (0, 0)
+      | "2" -> (1, 0)
       | v ->
         of_sexp_errorf loc
           "Unsupported version %S, only version 1 is supported" v)
   in
   sum
     [ "dune",
-      (version >>= fun () ->
-       get_all >>= fun parsing_context ->
-       list raw >>|
-       parse_sub_systems ~parsing_context)
+      (version >>= fun version ->
+       set (Syntax.key Stanza.syntax) version
+         (get_all >>= fun parsing_context ->
+          list raw >>|
+          parse_sub_systems ~parsing_context))
     ]
 
 let load fname =
   Io.with_lexbuf_from_file fname ~f:(fun lexbuf ->
-    let (tokens, version_loc, version) =
-      let rec loop = function
-        | [_; _; _] as a -> List.rev a
-        | acc ->
-          begin match (Sexp.Lexer.token lexbuf : Sexp.Lexer.Token.t) with
-          | Eof -> List.rev acc
-          | t -> loop (t :: acc)
-          end
-      in
-      let loc = Sexp.Loc.of_lexbuf lexbuf in
-      match loop [] with
-      | [Lparen; Atom (A "dune"); Atom s] as tokens ->
-        (tokens, loc, Sexp.Atom.to_string s)
-      | _ -> Loc.fail loc "Unable to read (dune x.y ..) line file"
+    (* Installed dune files are versioned but they don't use the
+       [(lang ...)] line which was introduced after. Installed dune
+       files in version 1 are using the jbuild syntax and version 2
+       are using the dune syntax, so we start by lexing the first
+       tokens with the dune lexer until we reach the file version, at
+       which point we can decide what lexer to use for the reset of
+       the file. *)
+    let state = ref 0 in
+    let lexer = ref Sexp.Lexer.token in
+    let lexer lb =
+      let token : Sexp.Lexer.Token.t = !lexer lb in
+      (match !state, token with
+       | 0, Lparen -> state := 1
+       | 1, Atom (A "dune") -> state := 2
+       | 2, Atom (A "1") -> state := 3; lexer := Sexp.Lexer.jbuild_token
+       | 2, Atom (A "2") -> state := 3; lexer := Sexp.Lexer.token
+       | 2, Atom (A version) ->
+         Loc.fail (Sexp.Loc.of_lexbuf lexbuf) "Unsupported version %S" version
+       | 3, _ -> ()
+       | _ ->
+         Loc.fail (Sexp.Loc.of_lexbuf lexbuf)
+           "This <lib>.dune file looks invalid, it should \
+            contain a S-expression of the form (dune x.y ..)"
+      );
+      token
     in
-    let (lexer, syntax) =
-      match version with
-      | "1" -> (Sexp.Lexer.jbuild_token, (0, 0))
-      | "2" -> (Sexp.Lexer.token, (1, 0))
-      | _   -> Loc.fail version_loc "unknown version %S" version
-    in
-    (* push back the tokens that we already read *)
-    let lexer =
-      let pending_tokens = ref tokens in
-      fun lb ->
-        match !pending_tokens with
-        | [] -> lexer lb
-        | x :: xs -> pending_tokens := xs; x
-    in
-    Sexp.Of_sexp.parse of_sexp
-      (Univ_map.singleton (Syntax.key Stanza.syntax) syntax)
+    Sexp.Of_sexp.parse of_sexp Univ_map.empty
       (Sexp.Parser.parse ~lexer ~mode:Single lexbuf))
 
 let gen ~(dune_version : Syntax.Version.t) confs =

From e09695e116c35770c50917a7bc92f9c183e4ecea Mon Sep 17 00:00:00 2001
From: Rudi Grinberg <rudi.grinberg@gmail.com>
Date: Tue, 3 Jul 2018 16:36:11 +0700
Subject: [PATCH 19/19] Relax versions for subsystems

Signed-off-by: Rudi Grinberg <rudi.grinberg@gmail.com>
---
 src/installed_dune_file.ml | 4 ++--
 src/stanza.ml              | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/installed_dune_file.ml b/src/installed_dune_file.ml
index 0102555e..c8bfae70 100644
--- a/src/installed_dune_file.ml
+++ b/src/installed_dune_file.ml
@@ -99,8 +99,8 @@ let gen ~(dune_version : Syntax.Version.t) confs =
     ; Sexp.unsafe_atom_of_string
         (match dune_version with
          | (0, 0) -> "1"
-         | (1, 0) -> "2"
-         | _ ->
+         | (x, _) when x >= 1 -> "2"
+         | (_, _) ->
            Exn.code_error "Cannot generate dune with unknown version"
              ["dune_version", Syntax.Version.sexp_of_t dune_version])
     ; List sexps
diff --git a/src/stanza.ml b/src/stanza.ml
index 898257f2..c7744586 100644
--- a/src/stanza.ml
+++ b/src/stanza.ml
@@ -16,7 +16,7 @@ module File_kind = struct
   type t = Sexp.syntax = Jbuild | Dune
 
   let of_syntax = function
-    | (0, 0) -> Jbuild
+    | (0, _) -> Jbuild
     | (_, _) -> Dune
 end