[3.20] backport #12320 (#12384)

Signed-off-by: Hugo Heuzard <[email protected]>
Signed-off-by: Etienne Marais <[email protected]>
Co-authored-by: Hugo Heuzard <[email protected]>

Author: maiste

doc/changes/12320.md

@@ -0,0 +1 @@
+- Fix jsoo separate compilation with modules_without_implementation. Regression introduced in #10767. (fixes #12306 @hhugo)

src/dune_rules/jsoo/jsoo_rules.ml

@@ -668,6 +668,7 @@ let build_cm cctx ~dir ~in_context ~mode ~src ~obj_dir ~deps ~config:config_opt
         |> Action_builder.map ~f:Config.of_flags
       | Some config -> Action_builder.return config
     in
+    let deps = List.filter deps ~f:(fun m -> Module.has m ~ml_kind:Impl) in
     (Path.build (in_build_dir ctx ~config [ "stdlib"; with_js_ext ~mode "stdlib.cma" ])
      :: List.concat_map libs ~f:(fun lib -> jsoo_archives ~mode ctx config lib))
     @ List.map deps ~f:(fun m ->

test/blackbox-tests/test-cases/jsoo/without_implem.t/run.t

@@ -0,0 +1,20 @@
+  $ cat > dune-project <<EOF
+  > (lang dune 3.20)
+  > EOF
+
+  $ cat > dune <<EOF
+  > (executable
+  >  (name main)
+  >  (modes js)
+  >  (modules_without_implementation interface))
+  > EOF
+
+  $ cat > main.ml <<EOF
+  > let _ = Interface.Foo
+  > EOF
+
+  $ cat > interface.mli <<EOF
+  > type t = Foo
+  > EOF
+
+  $ dune build