Adds private directory in the right case

  - a library sees its private directory
  - a library doesn't see other private directory

Signed-off-by: François Bobot <[email protected]>

Author: bobot

CHANGES.md

@@ -1,6 +1,8 @@
 unreleased
 ----------
 
+- Fix merlin handling of private module visibility (#1653 @bobot)
+
 - unstable-fmt: use boxes to wrap some lists (#1608, fix #1153, @emillon,
   thanks to @rgrinberg)
 

src/lib_rules.ml

@@ -538,13 +538,19 @@ module Gen (P : Install_rules.Params) = struct
       ; compile_info
       };
 
+    let objs_dirs = Path.Set.singleton obj_dir in
+    let objs_dirs = if Lib_modules.has_private_modules lib_modules then
+        Path.Set.add objs_dirs private_obj_dir
+      else objs_dirs in
+
     (cctx,
      Merlin.make ()
        ~requires:(Lib.Compile.requires compile_info)
        ~flags
        ~preprocess:(Buildable.single_preprocess lib.buildable)
        ~libname:(snd lib.name)
-       ~objs_dirs:(Path.Set.singleton obj_dir))
+       ~objs_dirs
+    )
 
   let rules (lib : Library.t) ~dir_contents ~dir ~expander ~scope
         ~dir_kind : Compilation_context.t * Merlin.t =

src/merlin.ml

@@ -144,10 +144,7 @@ let dot_merlin sctx ~dir ~more_src_dirs ~scope ~dir_kind
                   Lib.src_dir lib
                   |> Path.drop_optional_build_context)
               ,
-              let obj_dirs = Path.Set.add obj_dirs (Lib.obj_dir lib) in
-              match Lib.private_obj_dir lib with
-              | None -> obj_dirs
-              | Some private_obj_dir -> Path.Set.add obj_dirs private_obj_dir
+              Path.Set.add obj_dirs (Lib.obj_dir lib)
             ))
         in
         let src_dirs =

test/blackbox-tests/test-cases/merlin-tests/run.t

@@ -11,7 +11,6 @@
   B $LIB_PREFIX/lib/ocaml
   B ../_build/default/exe/.x.eobjs
   B ../_build/default/lib/.foo.objs
-  B ../_build/default/lib/.foo.objs/.private
   S $LIB_PREFIX/lib/bytes
   S $LIB_PREFIX/lib/findlib
   S $LIB_PREFIX/lib/ocaml
@@ -25,6 +24,7 @@
   B $LIB_PREFIX/lib/ocaml
   B ../_build/default/lib/.bar.objs
   B ../_build/default/lib/.foo.objs
+  B ../_build/default/lib/.foo.objs/.private
   S $LIB_PREFIX/lib/bytes
   S $LIB_PREFIX/lib/findlib
   S $LIB_PREFIX/lib/ocaml