From 5f3c6817e5afce11a320d425760cfcfcb6b8f011 Mon Sep 17 00:00:00 2001
From: Antonio Nuno Monteiro <anmonteiro@gmail.com>
Date: Tue, 7 Apr 2026 01:10:06 -0700
Subject: [PATCH] test(melange): show underspecified dependencies during
 emission

Signed-off-by: Antonio Nuno Monteiro <anmonteiro@gmail.com>
---
 .../emit-local-transitive-private-module.t    | 75 +++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 test/blackbox-tests/test-cases/melange/emit-local-transitive-private-module.t

diff --git a/test/blackbox-tests/test-cases/melange/emit-local-transitive-private-module.t b/test/blackbox-tests/test-cases/melange/emit-local-transitive-private-module.t
new file mode 100644
index 00000000000..9432639fb68
--- /dev/null
+++ b/test/blackbox-tests/test-cases/melange/emit-local-transitive-private-module.t
@@ -0,0 +1,75 @@
+When emitting JS for a same-workspace Melange library, Dune must stage the
+transitive implementation closure, even across `.mli` boundaries.
+
+  $ mkdir -p lib app
+
+  $ cat > dune-project <<'EOF'
+  > (lang dune 3.20)
+  > (using melange 0.1)
+  > (package (name repro))
+  > EOF
+
+  $ cat > lib/dune <<'EOF'
+  > (library
+  >  (name foo)
+  >  (public_name repro.foo)
+  >  (wrapped true)
+  >  (libraries melange)
+  >  (modes melange))
+  > EOF
+
+  $ cat > lib/foo.ml <<'EOF'
+  > module Foo_map = Foo_map
+  > EOF
+
+  $ cat > lib/foo_map.mli <<'EOF'
+  > module Int = Foo_mapInt
+  > val size : Int.t -> int
+  > EOF
+
+  $ cat > lib/foo_map.ml <<'EOF'
+  > module Int = Foo_mapInt
+  > let size x = Int.size x
+  > EOF
+
+  $ cat > lib/foo_mapInt.mli <<'EOF'
+  > type t
+  > val size : t -> int
+  > EOF
+
+  $ cat > lib/foo_mapInt.ml <<'EOF'
+  > type t = Foo_internalMapInt.t
+  > let size x = Foo_internalMapInt.size x
+  > EOF
+
+  $ cat > lib/foo_internalMapInt.mli <<'EOF'
+  > type t
+  > val size : t -> int
+  > EOF
+
+  $ cat > lib/foo_internalMapInt.ml <<'EOF'
+  > type t = int array
+  > let size x = Foo_internalAVLtree.size x
+  > EOF
+
+  $ cat > lib/foo_internalAVLtree.ml <<'EOF'
+  > let size x = Array.length x
+  > EOF
+
+  $ cat > app/dune <<'EOF'
+  > (melange.emit
+  >  (target dist)
+  >  (alias mel)
+  >  (emit_stdlib false)
+  >  (libraries repro.foo))
+  > EOF
+
+  $ cat > app/main.ml <<'EOF'
+  > let () = ignore (Foo.Foo_map.Int.size (Obj.magic 0))
+  > EOF
+
+  $ dune rules --deps app/dist/node_modules/repro.foo/foo_map.js \
+  >   | sed -n 's#.*\(lib/.foo\.objs/melange/[^)]*\).*#\1#p'
+  lib/.foo.objs/melange/foo__.cmj
+  lib/.foo.objs/melange/foo__Foo_map.cmj
+  lib/.foo.objs/melange/foo__Foo_mapInt.cmj