target hint: suffix directory targets with /

Signed-off-by: Etienne Millon <[email protected]>

bin/target.ml

@@ -23,36 +23,37 @@ let target_hint (_setup : Dune_rules.Main.build_system) path =
   assert (Path.is_managed path);
   let open Memo.O in
   let sub_dir = Option.value ~default:path (Path.parent path) in
-  (* CR-someday amokhov:
-
-     We currently provide the same hint for all targets. It would be nice to
-     indicate whether a hint corresponds to a file or to a directory target. *)
   let root =
     match sub_dir with
     | External _ -> (* checked above *) assert false
     | In_source_tree d -> d
     | In_build_dir d -> Path.Build.drop_build_context_exn d
   in
-  let+ candidates =
-    Load_rules.all_direct_targets (Some root) >>| Path.Build.Map.keys
-  in
-  let candidates =
-    if Path.is_in_build_dir path then List.map ~f:Path.build candidates
-    else
-      List.map candidates ~f:(fun path ->
-          match Path.Build.extract_build_context path with
-          | None -> Path.build path
-          | Some (_, path) -> Path.source path)
-  in
+  let+ candidates = Load_rules.all_direct_targets (Some root) in
+  let in_build = Path.is_in_build_dir path in
   let candidates =
-    (* Only suggest hints for the basename, otherwise it's slow when there are
-       lots of files *)
-    List.filter_map candidates ~f:(fun path ->
+    Path.Build.Map.foldi candidates ~init:String.Set.empty
+      ~f:(fun path (kind : Load_rules.target_type) acc ->
+        let path =
+          if in_build then Path.build path
+          else
+            match Path.Build.extract_build_context path with
+            | None -> Path.build path
+            | Some (_, path) -> Path.source path
+        in
+        (* Only suggest hints for the basename, otherwise it's slow when there are
+           lots of files *)
         if Path.equal (Path.parent_exn path) sub_dir then
-          Some (Path.to_string path)
-        else None)
+          let path_s = Path.to_string path in
+          let s =
+            match kind with
+            | File -> path_s
+            | Directory -> path_s ^ "/"
+          in
+          String.Set.add acc s
+        else acc)
+    |> String.Set.to_list
   in
-  let candidates = String.Set.of_list candidates |> String.Set.to_list in
   User_message.did_you_mean (Path.to_string path) ~candidates
 
 let resolve_path path ~(setup : Dune_rules.Main.build_system) =

test/blackbox-tests/test-cases/directory-targets/main.t

@@ -108,7 +108,7 @@ Hints for directory targets.
 
   $ dune build outputs
   Error: Don't know how to build outputs
-  Hint: did you mean output?
+  Hint: did you mean output/?
   [1]
 
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