refactor: get rid of dummy ocamlobjinfo targets (#12533)

Now they're invisible to the user.

Signed-off-by: Rudi Grinberg <[email protected]>

Author: rgrinberg

src/dune_rules/command.ml

@@ -137,13 +137,13 @@ let run ~dir ?sandbox ?stdout_to prog args =
   run_dyn_prog ~dir ?sandbox ?stdout_to (Action_builder.return prog) args
 ;;
 
-let run' ~dir prog args =
+let run' ?sandbox ~dir prog args =
   let open Action_builder.O in
   let+ () = dep_prog prog
   and+ args = expand_no_targets ~dir (S args) in
   Action.Run (prog, Appendable_list.to_immutable_array args)
   |> Action.chdir dir
-  |> Action.Full.make
+  |> Action.Full.make ?sandbox
 ;;
 
 let quote_args =

src/dune_rules/command.mli

@@ -90,7 +90,8 @@ val run
 
 (** Same as [run], but for actions that don't produce targets *)
 val run'
-  :  dir:Path.t
+  :  ?sandbox:Sandbox_config.t
+  -> dir:Path.t
   -> Action.Prog.t
   -> Args.without_targets Args.t list
   -> Action.Full.t Action_builder.t

src/dune_rules/dep_rules.ml

@@ -20,7 +20,7 @@ let ooi_deps
       (sourced_module : Modules.Sourced_module.t)
   =
   let m = Modules.Sourced_module.to_module sourced_module in
-  let* write, read =
+  let* read =
     let unit =
       let cm_kind =
         match ml_kind with
@@ -50,8 +50,7 @@ let ooi_deps
          then None
          else Module_name.Unique.Map.find vlib_obj_map dep))
   in
-  let+ () = add_rule write
-  and+ () =
+  let+ () =
     add_rule
       (let target =
          Obj_dir.Module.dep obj_dir (Transitive (m, ml_kind)) |> Option.value_exn

src/dune_rules/ocamlobjinfo.mli

@@ -11,7 +11,7 @@ val rules
   -> dir:Path.Build.t
   -> sandbox:Sandbox_config.t option
   -> unit:Path.t
-  -> Action.Full.t Action_builder.With_targets.t * t Action_builder.t
+  -> t Action_builder.t
 
 (** For testing only *)
 val parse : string -> t

src/dune_rules/ocamlobjinfo.mll

@@ -39,10 +39,6 @@ and impls acc = parse
 let parse s = ocamlobjinfo empty (Lexing.from_string s)
 
 let rules (ocaml : Ocaml_toolchain.t) ~dir ~sandbox ~unit =
-  let output =
-    Path.Build.relative dir (Path.basename unit)
-    |> Path.Build.extend_basename ~suffix:".ooi-deps"
-  in
   let no_approx =
     if Ocaml.Version.ooi_supports_no_approx ocaml.version then
       [Command.Args.A "-no-approx"]
@@ -55,14 +51,26 @@ let rules (ocaml : Ocaml_toolchain.t) ~dir ~sandbox ~unit =
     else
       []
   in
-  ( Command.run ?sandbox
+  let observing_facts =
+    Dep.Facts.singleton (Dep.file unit) (Dep.Fact.nothing)
+  in
+  let open Action_builder.O in
+  let* action =
+    Command.run' ?sandbox
       ~dir:(Path.build dir) ocaml.ocamlobjinfo
       (List.concat
          [ no_approx
          ; no_code
          ; [ Dep unit ]
          ])
-      ~stdout_to:output
-  , Action_builder.map ~f:parse (Action_builder.contents (Path.build output))
-  )
+  in
+  (Dune_engine.Build_system.execute_action_stdout
+    ~observing_facts
+    { Rule.Anonymous_action.action
+    ; loc = Loc.none
+    ; dir
+    ; alias = None
+    }
+  |> Action_builder.of_memo)
+  >>| parse
 }