1 files changed, 44 insertions, 0 deletions
diff --git a/testsuite/tests/typing-modules/functors.ml b/testsuite/tests/typing-modules/functors.ml
index 932bc9f9fc..3fa34a1d89 100644
--- a/testsuite/tests/typing-modules/functors.ml
+++ b/testsuite/tests/typing-modules/functors.ml
@@ -1701,3 +1701,47 @@ Error: The functor application Bar(A)(FiveArgsExt)(TY)(TY)(TY)(TY)(TY) is ill-ty
        8. Module TY matches the expected module type ty
        9. Module TY matches the expected module type ty
 |}]
+
+module Shape_arg = struct
+  module M1 (Arg1 : sig end) = struct
+    module type S1 = sig
+      type t
+    end
+  end
+
+  module type S2 = sig
+    module Make (Arg2 : sig end) : M1(Arg2).S1
+  end
+
+  module M2 : S2 = struct
+    module Make (Arg3 : sig end) = struct
+      type t = T
+    end
+  end
+
+  module M3 (Arg4 : sig end) = struct
+    module type S3 = sig
+      type t = M2.Make(Arg4).t
+    end
+  end
+
+  module M4 (Arg5 : sig end) : M3(Arg5).S3 = struct
+    module M5 = M2.Make (Arg5)
+
+    type t = M5.t
+  end
+end
+[%%expect{|
+module Shape_arg :
+  sig
+    module M1 :
+      functor (Arg1 : sig end) -> sig module type S1 = sig type t end end
+    module type S2 =
+      sig module Make : functor (Arg2 : sig end) -> M1(Arg2).S1 end
+    module M2 : S2
+    module M3 :
+      functor (Arg4 : sig end) ->
+        sig module type S3 = sig type t = M2.Make(Arg4).t end end
+    module M4 : functor (Arg5 : sig end) -> M3(Arg5).S3
+  end
+|}]