Introduce a bindings variable for actions

We need to know the bindings statically whenever they overwrite existing vars

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

src/gen_rules.ml

@@ -194,6 +194,7 @@ module Gen(P : Install_rules.Params) = struct
          (snd rule.action)
          ~loc:(fst rule.action)
          ~dir
+         ~bindings:(Pform.Map.of_bindings rule.deps)
          ~dep_kind:Required
          ~targets
          ~scope)
@@ -950,6 +951,7 @@ module Gen(P : Install_rules.Params) = struct
            ~loc
            ~dir
            ~dep_kind:Required
+           ~bindings:(Pform.Map.of_bindings alias_conf.deps)
            ~targets:Alias
            ~scope)
 

src/inline_tests.ml

@@ -220,6 +220,7 @@ include Sub_system.Register_end_point(
           (List.filter_map backends ~f:(fun (backend : Backend.t) ->
              Option.map backend.info.generate_runner ~f:(fun (loc, action) ->
                SC.Action.run sctx action ~loc
+                 ~bindings:Pform.Map.empty
                  ~extra_vars ~dir ~dep_kind:Required ~targets:Alias ~scope)))
         >>^ (fun actions ->
           Action.with_stdout_to target

src/jbuild.ml

@@ -239,6 +239,8 @@ module Bindings = struct
 
   type 'a t = 'a one list
 
+  let fold t ~f ~init = List.fold_left ~f:(fun acc x -> f x acc) ~init t
+
   let to_list =
     List.concat_map ~f:(function
       | Unnamed x -> [x]

src/jbuild.mli

@@ -90,6 +90,8 @@ module Bindings : sig
 
   val find : 'a t -> string -> 'a list option
 
+  val fold : 'a t -> f:('a one -> 'acc -> 'acc) -> init:'acc -> 'acc
+
   val empty : 'a t
 
   val to_list : 'a t -> 'a list

src/pform.ml

@@ -7,6 +7,7 @@ module Var = struct
     | First_dep
     | Deps
     | Targets
+    | Named_local
 
   let to_value_no_deps_or_targets t ~scope =
     match t with
@@ -14,6 +15,7 @@ module Var = struct
     | Project_root -> Some [Value.Dir (Scope.root scope)]
     | First_dep
     | Deps
+    | Named_local
     | Targets -> None
 end
 
@@ -141,6 +143,8 @@ module Map = struct
 
   let static_vars = String.Map.of_list_exn static_vars
 
+  let superpose = String.Map.superpose
+
   let rec expand t ~syntax_version ~var =
     let name = String_with_vars.Var.name var in
     Option.bind (String.Map.find t name) ~f:(fun v ->
@@ -176,4 +180,13 @@ module Map = struct
         else
           Syntax.Error.deleted_in (String_with_vars.Var.loc var)
             Stanza.syntax syntax_version ~what:(what var) ?repl)
+
+  let empty = String.Map.empty
+
+  let of_bindings =
+    Jbuild.Bindings.fold ~f:(fun x acc ->
+      match x with
+      | Unnamed _ -> acc
+      | Named (s, _) -> String.Map.add acc s (No_info Var.Named_local)
+    ) ~init:empty
 end

src/pform.mli

@@ -5,6 +5,7 @@ module Var : sig
     | First_dep
     | Deps
     | Targets
+    | Named_local
 
   val to_value_no_deps_or_targets : t -> scope:Scope.t -> Value.t list option
 end
@@ -41,9 +42,15 @@ module Map : sig
 
   val static_vars : Var.t t
 
+  val superpose : 'a t -> 'a t -> 'a t
+
+  val of_bindings : 'a Jbuild.Bindings.t -> Var.t t
+
   val expand
     :  'a t
     -> syntax_version:Syntax.Version.t
     -> var:String_with_vars.Var.t
     -> 'a option
+
+  val empty : 'a t
 end with type 'a var := 'a t

src/preprocessing.ml

@@ -462,6 +462,7 @@ let lint_module sctx ~dir ~dep_kind ~lint ~lib_name ~scope ~dir_kind =
                         ~loc
                         ~dir
                         ~dep_kind
+                        ~bindings:Pform.Map.empty
                         ~targets:(Static [])
                         ~scope)))
         | Pps { loc; pps; flags } ->
@@ -542,6 +543,7 @@ let make sctx ~dir ~dep_kind ~lint ~preprocess
                   ~loc
                   ~dir
                   ~dep_kind
+                  ~bindings:Pform.Map.empty
                   ~targets:(Static [dst])
                   ~scope))
            |> setup_reason_rules sctx ~dir in

src/super_context.ml

@@ -807,9 +807,10 @@ module Action = struct
           end
         end)
 
-  let run sctx ~loc ?(extra_vars=String.Map.empty)
+  let run sctx ~loc ?(extra_vars=String.Map.empty) ~bindings
         t ~dir ~dep_kind ~targets:targets_written_by_user ~scope
     : (Path.t Bindings.t, Action.t) Build.t =
+    ignore bindings;
     let map_exe = map_exe sctx in
     if targets_written_by_user = Alias then begin
       match Action.Infer.unexpanded_targets t with

src/super_context.mli

@@ -240,6 +240,7 @@ module Action : sig
     :  t
     -> loc:Loc.t
     -> ?extra_vars:Value.t list String.Map.t
+    -> bindings:Pform.Var.t Pform.Map.t
     -> Action.Unexpanded.t
     -> dir:Path.t
     -> dep_kind:Build.lib_dep_kind