[New Command] Expand PPX nodes

src/analysis/ppx_expand.ml

@@ -99,9 +99,13 @@ let get_ppxed_source ~ppxed_parsetree ~pos ppx_kind_with_attr :
     | Sig_item original_sg, _ -> (
         let signature_item (self : Ast_iterator.iterator)
             (new_sg : Parsetree.signature_item) =
-          match check_at_pos pos new_sg.psig_loc && original_sg <> new_sg with
-          | true -> signature := new_sg :: !signature
-          | false -> Ast_iterator.default_iterator.signature_item self new_sg
+          let included =
+            Location_aux.included new_sg.psig_loc ~into:original_sg.psig_loc
+          in
+          match included && original_sg <> new_sg, new_sg.psig_loc.loc_ghost with
+          | true, _ -> signature := new_sg :: !signature
+          | false, false -> Ast_iterator.default_iterator.signature_item self new_sg
+          | false, true -> () (* We don't enter nested ppxes *)
         in
         let iterator = { Ast_iterator.default_iterator with signature_item } in
         match ppxed_parsetree with

tests/test-dirs/expand_node/ppx-tests.t/run.t

@@ -381,44 +381,14 @@ Module type declaration in signature
   $ dune build
 
 on attribute name deriving of type t
-TODO: a cursor here should only output the derived t and now the whole module
+a cursor here should only output the derived t 
   $ $MERLIN  single expand-ppx -position 2:14 -filename ./apc.mli < ./apc.mli
   {
     "class": "return",
     "value": {
-      "code": "module type Stack  =
-    sig
-      type t[@@deriving rename]
-      include sig [@@@ocaml.warning \"-32\"] type t_renamed end[@@ocaml.doc
-                                                               \"@inline\"]
-      [@@merlin.hide ]
-      type stack
-      val empty : stack
-      val is_empty : stack -> bool
-      val push : t -> stack -> stack
-      val pop : stack -> stack
-      val peek : stack -> t
-    end[@@deriving rename]
-  include
-    sig
-      [@@@ocaml.warning \"-32\"]
-      module type Stack_renamed  =
-        sig
-          type t[@@deriving rename]
-          include sig [@@@ocaml.warning \"-32\"] type t_renamed end[@@ocaml.doc
-                                                                   \"@inline\"]
-          [@@merlin.hide ]
-          include sig [@@@ocaml.warning \"-32\"] type t_renamed end[@@ocaml.doc
-                                                                   \"@inline\"]
-          [@@merlin.hide ]
-          type stack
-          val empty : stack
-          val is_empty : stack -> bool
-          val push : t -> stack -> stack
-          val pop : stack -> stack
-          val peek : stack -> t
-        end
-    end[@@ocaml.doc \"@inline\"][@@merlin.hide ]",
+      "code": "include sig [@@@ocaml.warning \"-32\"] type t_renamed end[@@ocaml.doc
+                                                           \"@inline\"][@@merlin.hide
+                                                                      ]",
       "deriver": {
         "start": {
           "line": 2,