Extensions versioning (#3270)

Improve and check extensions versioning.

Signed-off-by: Ulysse Gérard <thevoodoos@gmail.com>

Co-authored-by: Jeremie Dimino <jeremie@dimino.org>

CHANGES.md

@@ -16,6 +16,11 @@ Unreleased
 
 - [coq] Support for theory dependencies and compositional builds using
   new field `(theories ...)` (#2053, @ejgallego, @rgrinberg)
+
+- From now on, each version of a syntax extension must be explicitely tied to a
+  minimum version of the dune language. Inconsistent versions in a
+  `dune-project` will trigger a warning for version <=2.4 and an error for
+  versions >2.4 of the dune language. (#3270, fixes #2957, @voodoos)
 
 2.4.0 (06/03/2020)
 ------------------

doc/dune-files.rst

@@ -12,7 +12,7 @@ like:
 
 .. code:: scheme
 
-          (lang dune 2.4)
+          (lang dune 2.5)
 
 Additionally, they can contains the following stanzas.
 
@@ -1696,7 +1696,7 @@ a typical ``dune-workspace`` file looks like:
 
 .. code:: scheme
 
-    (lang dune 2.4)
+    (lang dune 2.5)
     (context (opam (switch 4.02.3)))
     (context (opam (switch 4.03.0)))
     (context (opam (switch 4.04.0)))
@@ -1708,7 +1708,7 @@ containing exactly:
 
 .. code:: scheme
 
-    (lang dune 2.4)
+    (lang dune 2.5)
     (context default)
 
 This allows you to use an empty ``dune-workspace`` file to mark the root of your

doc/opam.rst

@@ -94,7 +94,7 @@ configuration will tell ``dune`` to generate two opam files: ``cohttp.opam`` and
 
 .. code:: scheme
 
-   (lang dune 2.4)
+   (lang dune 2.5)
    (name cohttp)
 
    (generate_opam_files true)

src/dune/action_plugin.ml

@@ -1,3 +1,3 @@
 let syntax =
   Dune_lang.Syntax.create ~name:"action-plugin" ~desc:"action plugin extension"
-    [ (0, 1) ]
+    [ ((0, 1), `Since (2, 0)) ]

src/dune/cinaps.ml

@@ -16,7 +16,8 @@ let name = "cinaps"
 type Stanza.t += T of t
 
 let syntax =
-  Dune_lang.Syntax.create ~name ~desc:"the cinaps extension" [ (1, 0) ]
+  Dune_lang.Syntax.create ~name ~desc:"the cinaps extension"
+    [ ((1, 0), `Since (1, 11)) ]
 
 let alias = Alias.make (Alias.Name.of_string name)
 

src/dune/dune_file.ml

@@ -22,7 +22,8 @@ let relative_file =
 let library_variants =
   let syntax =
     Dune_lang.Syntax.create ~name:"library_variants"
-      ~desc:"the experimental library variants feature." [ (0, 2) ]
+      ~desc:"the experimental library variants feature."
+      [ ((0, 1), `Since (1, 9)); ((0, 2), `Since (1, 11)) ]
   in
   Dune_project.Extension.register_simple ~experimental:true syntax
     (Dune_lang.Decoder.return []);
@@ -1538,7 +1539,8 @@ module Executables = struct
   let bootstrap_info_extension =
     let syntax =
       Dune_lang.Syntax.create ~name:"dune-bootstrap-info"
-        ~desc:"private extension to handle Dune bootstrap" [ (0, 1) ]
+        ~desc:"private extension to handle Dune bootstrap"
+        [ ((0, 1), `Since (2, 0)) ]
     in
     Dune_project.Extension.register syntax (return ((), [])) Dyn.Encoder.unit
 
@@ -1992,7 +1994,7 @@ module Coq = struct
 
   let syntax =
     Dune_lang.Syntax.create ~name:"coq" ~desc:"the coq extension (experimental)"
-      [ (0, 1) ]
+      [ ((0, 1), `Since (1, 9)) ]
 
   let coq_public_decode =
     map_validate

src/dune/dune_project.ml

@@ -247,7 +247,9 @@ include Dune_lang.Versioned_file.Make (struct
 end)
 
 let default_dune_language_version =
-  ref (Dune_lang.Syntax.greatest_supported_version Stanza.syntax)
+  ref
+    (Option.value_exn
+       (Dune_lang.Syntax.greatest_supported_version Stanza.syntax))
 
 let get_dune_lang () =
   { (Lang.get_exn "dune") with version = !default_dune_language_version }
@@ -370,58 +372,64 @@ module Extension = struct
     let (_ : unit t) = register ?experimental syntax unit_stanzas Unit.to_dyn in
     ()
 
-  let instantiate ~loc ~parse_args (name_loc, name) (ver_loc, ver) =
+  let instantiate ~dune_lang_ver ~loc ~parse_args (name_loc, name) (ver_loc, ver)
+      =
     match Table.find extensions name with
     | None ->
       User_error.raise ~loc:name_loc
         [ Pp.textf "Unknown extension %S." name ]
         ~hints:
           (User_message.did_you_mean name ~candidates:(Table.keys extensions))
     | Some t ->
-      Dune_lang.Syntax.check_supported (syntax t) (ver_loc, ver);
+      Dune_lang.Syntax.check_supported ~dune_lang_ver (syntax t) (ver_loc, ver);
       { extension = t; version = ver; loc; parse_args }
 
   (* Extensions that are not selected in the dune-project file are automatically
      available at their latest version. When used, dune will automatically edit
      the dune-project file. *)
-  let automatic ~project_file ~f =
+  let automatic ~lang ~project_file ~f =
     Table.foldi extensions ~init:[] ~f:(fun name extension acc ->
         if f name then
           let version =
             if is_experimental extension then
-              (0, 0)
+              Some (0, 0)
             else
-              Dune_lang.Syntax.greatest_supported_version (syntax extension)
+              let dune_lang_ver = lang.Lang.Instance.version in
+              Dune_lang.Syntax.greatest_supported_version ~dune_lang_ver
+                (syntax extension)
           in
-          let parse_args p =
-            let open Dune_lang.Decoder in
-            let dune_project_edited = ref false in
-            let arg, stanzas =
-              parse (enter p) Univ_map.empty (List (Loc.of_pos __POS__, []))
+          match version with
+          | Some version ->
+            let parse_args p =
+              let open Dune_lang.Decoder in
+              let dune_project_edited = ref false in
+              let arg, stanzas =
+                parse (enter p) Univ_map.empty (List (Loc.of_pos __POS__, []))
+              in
+              let result_stanzas =
+                List.map stanzas ~f:(fun (name, p) ->
+                    ( name
+                    , let* () = return () in
+                      if not !dune_project_edited then (
+                        dune_project_edited := true;
+                        ignore
+                          ( Project_file_edit.append project_file
+                              (Dune_lang.to_string
+                                 (List
+                                    [ Dune_lang.atom "using"
+                                    ; Dune_lang.atom name
+                                    ; Dune_lang.atom
+                                        (Dune_lang.Syntax.Version.to_string
+                                           version)
+                                    ]))
+                            : created_or_already_exist )
+                      );
+                      p ))
+              in
+              (arg, result_stanzas)
             in
-            let result_stanzas =
-              List.map stanzas ~f:(fun (name, p) ->
-                  ( name
-                  , let* () = return () in
-                    if not !dune_project_edited then (
-                      dune_project_edited := true;
-                      ignore
-                        ( Project_file_edit.append project_file
-                            (Dune_lang.to_string
-                               (List
-                                  [ Dune_lang.atom "using"
-                                  ; Dune_lang.atom name
-                                  ; Dune_lang.atom
-                                      (Dune_lang.Syntax.Version.to_string
-                                         version)
-                                  ]))
-                          : created_or_already_exist )
-                    );
-                    p ))
-            in
-            (arg, result_stanzas)
-          in
-          { extension; version; loc = Loc.none; parse_args } :: acc
+            { extension; version; loc = Loc.none; parse_args } :: acc
+          | None -> acc
         else
           acc)
 end
@@ -438,7 +446,7 @@ let interpret_lang_and_extensions ~(lang : Lang.Instance.t) ~explicit_extensions
       [ Pp.textf "Extension %S specified for the second time." name ]
   | Ok map ->
     let implicit_extensions =
-      Extension.automatic ~project_file ~f:(fun name ->
+      Extension.automatic ~lang ~project_file ~f:(fun name ->
           not (String.Map.mem map name))
     in
     let extensions =
@@ -583,7 +591,8 @@ let parse ~dir ~lang ~opam_packages ~file =
           and+ parse_args = capture in
           (* We don't parse the arguments quite yet as we want to set the
              version of extensions before parsing them. *)
-          Extension.instantiate ~loc ~parse_args name ver)
+          Extension.instantiate ~dune_lang_ver:lang.Lang.Instance.version ~loc
+            ~parse_args name ver)
      and+ implicit_transitive_deps =
        field_o_b "implicit_transitive_deps"
          ~check:(Dune_lang.Syntax.since Stanza.syntax (1, 7))

src/dune/format_config.ml

@@ -4,7 +4,11 @@ open Dune_lang.Decoder
 
 let syntax =
   Dune_lang.Syntax.create ~name:"fmt"
-    ~desc:"integration with automatic formatters" [ (1, 2) ]
+    ~desc:"integration with automatic formatters"
+    [ ((1, 0), `Since (1, 4))
+    ; ((1, 1), `Since (1, 7))
+    ; ((1, 2), `Since (1, 11))
+    ]
 
 module Language = struct
   type t =

src/dune/install_rules.ml

@@ -295,7 +295,7 @@ let gen_dune_package sctx pkg =
   let meta_template = Package_paths.meta_template ctx pkg in
   let name = pkg.name in
   let dune_version =
-    Dune_lang.Syntax.greatest_supported_version Stanza.syntax
+    Option.value_exn (Dune_lang.Syntax.greatest_supported_version Stanza.syntax)
   in
   let lib_entries = Super_context.lib_entries_of_package sctx pkg.name in
   let deprecated_dune_packages =

src/dune/mdx.ml

@@ -128,7 +128,7 @@ type Stanza.t += T of t
 let syntax =
   let name = "mdx" in
   let desc = "mdx extension to verify code blocks in .md files" in
-  Dune_lang.Syntax.create ~name ~desc [ (0, 1) ]
+  Dune_lang.Syntax.create ~name ~desc [ ((0, 1), `Since (2, 4)) ]
 
 let default_files =
   let has_extention ext s = String.equal ext (Filename.extension s) in

src/dune/menhir_stanza.ml

@@ -1,3 +1,7 @@
 let syntax =
   Dune_lang.Syntax.create ~name:"menhir" ~desc:"the menhir extension"
-    [ (1, 1); (2, 1) ]
+    [ ((1, 0), `Since (1, 0))
+    ; ((1, 1), `Since (1, 4))
+    ; ((2, 0), `Since (1, 4))
+    ; ((2, 1), `Since (2, 2))
+    ]

src/dune/ocaml_stdlib.ml

@@ -9,7 +9,7 @@ let syntax =
     Dune_lang.Syntax.create
       ~name:"experimental_building_ocaml_compiler_with_dune"
       ~desc:"experimental feature for building the compiler with dune"
-      [ (0, 1) ]
+      [ ((0, 1), `Since (1, 3)) ]
   in
   Dune_project.Extension.register_simple ~experimental:true syntax
     (Dune_lang.Decoder.return []);

src/dune/stanza.ml

@@ -6,8 +6,13 @@ module Parser = struct
   type nonrec t = string * t list Dune_lang.Decoder.t
 end
 
-let latest_version = (2, 4)
+let latest_version = (2, 5)
+
+let since v = (v, `Since v)
+
+let all_minors (major, minor) =
+  List.init (minor + 1) ~f:(fun i -> since (major, i))
 
 let syntax =
   Dune_lang.Syntax.create ~name:"dune" ~desc:"the dune language"
-    [ (1, 12); latest_version ]
+    (all_minors (1, 12) @ all_minors latest_version)