Merge pull request #1091 from ocaml/compiler-version-predicates

Extract predicates for compiler versions

src/context.ml

@@ -50,7 +50,7 @@ type t =
   ; natdynlink_supported    : bool
   ; ocaml_config            : Ocaml_config.t
   ; version_string          : string
-  ; version                 : int * int * int
+  ; version                 : Ocaml_version.t
   ; stdlib_dir              : Path.t
   ; ccomp_type              : string
   ; c_compiler              : string
@@ -274,16 +274,16 @@ let create ~(kind : Kind.t) ~path ~env ~env_nodes ~name ~merlin ~targets
          ocaml_config_ok_exn
            (Ocaml_config.Vars.of_lines lines >>= Ocaml_config.make))
     >>= fun (findlib_path, ocfg) ->
-    let version = Ocaml_config.version ocfg in
+    let version = Ocaml_version.of_ocaml_config ocfg in
     let env =
-      (* See comment in ansi_color.ml for setup_env_for_colors. For
-         OCaml < 4.05, OCAML_COLOR is not supported so we use
-         OCAMLPARAM. OCaml 4.02 doesn't support 'color' in OCAMLPARAM,
-         so we just don't force colors with 4.02. *)
+      (* See comment in ansi_color.ml for setup_env_for_colors.
+         For versions where OCAML_COLOR is not supported, but 'color' is in
+         OCAMLPARAM, use the latter.
+         If 'color' is not supported, we just don't force colors with 4.02. *)
       if !Clflags.capture_outputs
       && Lazy.force Colors.stderr_supports_colors
-      && version >= (4, 03, 0)
-      && version <  (4, 05, 0) then
+      && Ocaml_version.supports_color_in_ocamlparam version
+      && not (Ocaml_version.supports_ocaml_color version) then
         let value =
           match Env.get env "OCAMLPARAM" with
           | None -> "color=always,_"
@@ -332,8 +332,8 @@ let create ~(kind : Kind.t) ~path ~env ~env_nodes ~name ~merlin ~targets
     in
     let stdlib_dir = Path.of_string (Ocaml_config.standard_library ocfg) in
     let natdynlink_supported = Ocaml_config.natdynlink_supported ocfg in
-    let version        = Ocaml_config.version ocfg        in
     let version_string = Ocaml_config.version_string ocfg in
+    let version        = Ocaml_version.of_ocaml_config ocfg in
     let arch_sixtyfour = Ocaml_config.word_size ocfg = 64 in
     Fiber.return
       { name

src/context.mli

@@ -90,7 +90,7 @@ type t =
 
   ; ocaml_config            : Ocaml_config.t
   ; version_string          : string
-  ; version                 : int * int * int
+  ; version                 : Ocaml_version.t
   ; stdlib_dir              : Path.t
   ; ccomp_type              : string
   ; c_compiler              : string

src/gen_rules.ml

@@ -17,7 +17,8 @@ module Gen(P : Install_rules.Params) = struct
   let sctx = P.sctx
   let ctx = SC.context sctx
 
-  let opaque = ctx.profile = "dev" && ctx.version >= (4, 03, 0)
+  let opaque =
+    ctx.profile = "dev" && Ocaml_version.supports_opaque_for_mli ctx.version
 
   (* +-----------------------------------------------------------------+
      | Library stuff                                                   |
@@ -143,10 +144,11 @@ module Gen(P : Install_rules.Params) = struct
           ]));
     dst
 
-  (* In 4.02, the compiler reads the cmi for module alias even with
-     [-w -49 -no-alias-deps], so we must sandbox the build of the
+  (* If the compiler reads the cmi for module alias even with
+     [-w -49 -no-alias-deps], we must sandbox the build of the
      alias module since the modules it references are built after. *)
-  let alias_module_build_sandbox = ctx.version < (4, 03, 0)
+  let alias_module_build_sandbox =
+    Ocaml_version.always_reads_alias_cmi ctx.version
 
   let library_rules (lib : Library.t) ~dir_contents ~dir ~scope
         ~compile_info ~dir_kind =

src/module_compilation.ml

@@ -95,10 +95,10 @@ let build_cm cctx ?sandbox ?(dynlink=true) ~dep_graphs ~cm_kind (m : Module.t) =
       in
       let dir, no_keep_locs =
         if CC.no_keep_locs cctx && cm_kind = Cmi then begin
-          if ctx.version < (4, 03, 0) then
-            (obj_dir, Arg_spec.As [])
+          if Ocaml_version.supports_no_keep_locs ctx.version then
+            (ctx.build_dir, Arg_spec.As ["-no-keep-locs"])
           else
-            (ctx.build_dir, As ["-no-keep-locs"])
+            (obj_dir, As [])
         end else
           (ctx.build_dir, As [])
       in

src/ocaml_version.ml

@@ -0,0 +1,19 @@
+type t = int * int * int
+
+let of_ocaml_config ocfg =
+  Ocaml_config.version ocfg
+
+let supports_no_keep_locs version =
+  version >= (4, 03, 0)
+
+let supports_opaque_for_mli version =
+  version >= (4, 03, 0)
+
+let always_reads_alias_cmi version =
+  version < (4, 03, 0)
+
+let supports_color_in_ocamlparam version =
+  version >= (4, 03, 0)
+
+let supports_ocaml_color version =
+  version >= (4, 05, 0)

src/ocaml_version.mli

@@ -0,0 +1,20 @@
+(** Version numbers for ocamlc and ocamlopt *)
+type t
+
+val of_ocaml_config : Ocaml_config.t -> t
+
+(** Does this support [-no-keep-locs]? *)
+val supports_no_keep_locs : t -> bool
+
+(** Does this support [-opaque] for [.mli] files? *)
+val supports_opaque_for_mli : t -> bool
+
+(** Does it read the [.cmi] file of module alias
+    even when [-no-alias-deps] is passed? *)
+val always_reads_alias_cmi : t -> bool
+
+(** Does this support ['color'] in [OCAMLPARAM]? *)
+val supports_color_in_ocamlparam : t -> bool
+
+(** Does this support [OCAML_COLOR]? *)
+val supports_ocaml_color : t -> bool