Exclude unreadable directories from File_tree.t

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

src/file_tree.ml

@@ -87,7 +87,7 @@ module Dir = struct
   type t =
     { path     : Path.t
     ; ignored  : bool
-    ; contents : (contents, string) Result.t Lazy.t
+    ; contents : contents Lazy.t
     ; project  : Dune_project.t
     }
 
@@ -109,20 +109,9 @@ module Dir = struct
   let path t = t.path
   let ignored t = t.ignored
 
-  let files     t =
-    match contents t with
-    | Ok t -> t.files
-    | Error _ -> String.Set.empty
-
-  let sub_dirs  t =
-    match contents t with
-    | Ok t -> t.sub_dirs
-    | Error _ -> String.Map.empty
-
-  let dune_file t =
-    match contents t with
-    | Ok t -> t.dune_file
-    | Error _ -> None
+  let files     t = (contents t).files
+  let sub_dirs  t = (contents t).sub_dirs
+  let dune_file t = (contents t).dune_file
 
   let project t = t.project
 
@@ -159,11 +148,7 @@ module Dir = struct
     Record
       [ "path", Path.to_dyn path
       ; "ignored", Bool ignored
-      ; "contents",
-        Result.to_dyn
-          dyn_of_contents
-          (fun e -> String e)
-          contents
+      ; "contents", dyn_of_contents contents
       ]
 
   let to_sexp t = Dyn.to_sexp (to_dyn t)
@@ -227,24 +212,17 @@ let readdir path =
 
 let load ?(warn_when_seeing_jbuild_file=true) path =
   let open Result.O in
-  let rec walk path ~dirs_visited ~project:parent_project ~data_only =
-    let dir_listing = lazy (readdir path) in
+  let rec walk path ~dirs_visited ~project:parent_project ~data_only : (_, _) Result.t =
+    let+ { dirs; files } = readdir path in
     let project =
       if data_only then
         Lazy.force parent_project
       else
-        let dir_listing = Lazy.force dir_listing in
-        match dir_listing with
-        | Error _ -> Lazy.force parent_project
-        | Ok dir_listing ->
-          let files = dir_listing.files in
-          match Dune_project.load ~dir:path ~files with
-          | Some p -> p
-          | None -> Lazy.force parent_project
+        match Dune_project.load ~dir:path ~files with
+        | Some p -> p
+        | None -> Lazy.force parent_project
     in
     let contents = lazy (
-      let+ dir_listing = Lazy.force dir_listing in
-      let files = dir_listing.files in
       let dune_file, sub_dirs =
         if data_only then
           (None, Sub_dirs.default)
@@ -285,9 +263,9 @@ let load ?(warn_when_seeing_jbuild_file=true) path =
       in
       let sub_dirs =
         Sub_dirs.eval sub_dirs
-          ~dirs:(List.map ~f:(fun (a, _, _) -> a) dir_listing.dirs) in
+          ~dirs:(List.map ~f:(fun (a, _, _) -> a) dirs) in
       let sub_dirs =
-        dir_listing.dirs
+        dirs
         |> List.fold_left ~init:String.Map.empty ~f:(fun acc (fn, path, file) ->
           let status =
             if Bootstrap.data_only_path path then
@@ -311,17 +289,26 @@ let load ?(warn_when_seeing_jbuild_file=true) path =
                     (Path.to_string_maybe_quoted first_path)
                     (Path.to_string_maybe_quoted path)
             in
-            walk path ~dirs_visited ~project:(lazy project) ~data_only
-            |> String.Map.add acc fn)
+            match
+              walk path ~dirs_visited ~project:(lazy project) ~data_only
+            with
+            | Ok dir -> String.Map.add acc fn dir
+            | Error _ -> acc)
       in
       { Dir. files; sub_dirs; dune_file })
     in
     Dir.create ~path ~contents ~ignored:data_only ~project
   in
-  walk path
+  match
+    walk path
     ~dirs_visited:(File.Map.singleton (File.of_path path) path)
     ~data_only:false
     ~project:Dune_project.anonymous
+  with
+  | Ok dir -> dir
+  | Error m ->
+    die "Unable to load source %[email protected]:%s@."
+      (Path.to_string_maybe_quoted path) m
 
 let fold = Dir.fold