3 files changed, 13 insertions, 10 deletions
diff --git a/src/nvim/api/private/helpers.c b/src/nvim/api/private/helpers.c
index 23d1540e2f..373e509120 100644
--- a/src/nvim/api/private/helpers.c
+++ b/src/nvim/api/private/helpers.c
@@ -851,15 +851,18 @@ static void init_type_metadata(Dictionary *metadata)
   Dictionary types = ARRAY_DICT_INIT;
 
   Dictionary buffer_metadata = ARRAY_DICT_INIT;
-  PUT(buffer_metadata, "id", INTEGER_OBJ(kObjectTypeBuffer));
+  PUT(buffer_metadata, "id",
+      INTEGER_OBJ(kObjectTypeBuffer - EXT_OBJECT_TYPE_SHIFT));
   PUT(buffer_metadata, "prefix", STRING_OBJ(cstr_to_string("nvim_buf_")));
 
   Dictionary window_metadata = ARRAY_DICT_INIT;
-  PUT(window_metadata, "id", INTEGER_OBJ(kObjectTypeWindow));
+  PUT(window_metadata, "id",
+      INTEGER_OBJ(kObjectTypeWindow - EXT_OBJECT_TYPE_SHIFT));
   PUT(window_metadata, "prefix", STRING_OBJ(cstr_to_string("nvim_win_")));
 
   Dictionary tabpage_metadata = ARRAY_DICT_INIT;
-  PUT(tabpage_metadata, "id", INTEGER_OBJ(kObjectTypeTabpage));
+  PUT(tabpage_metadata, "id",
+      INTEGER_OBJ(kObjectTypeTabpage - EXT_OBJECT_TYPE_SHIFT));
   PUT(tabpage_metadata, "prefix", STRING_OBJ(cstr_to_string("nvim_tabpage_")));
 
   PUT(types, "Buffer", DICTIONARY_OBJ(buffer_metadata));
diff --git a/src/nvim/msgpack_rpc/helpers.c b/src/nvim/msgpack_rpc/helpers.c
index ec35d56978..21acd6a394 100644
--- a/src/nvim/msgpack_rpc/helpers.c
+++ b/src/nvim/msgpack_rpc/helpers.c
@@ -20,13 +20,6 @@
 static msgpack_zone zone;
 static msgpack_sbuffer sbuffer;
 
-/// Value by which objects represented as EXT type are shifted
-///
-/// Subtracted when packing, added when unpacking. Used to allow moving
-/// buffer/window/tabpage block inside ObjectType enum. This block yet cannot be
-/// split or reordered.
-#define EXT_OBJECT_TYPE_SHIFT kObjectTypeBuffer
-
 #define HANDLE_TYPE_CONVERSION_IMPL(t, lt) \
   static bool msgpack_rpc_to_##lt(const msgpack_object *const obj, \
                                   Integer *const arg) \
diff --git a/src/nvim/msgpack_rpc/helpers.h b/src/nvim/msgpack_rpc/helpers.h
index 7d9f114140..0e4cd1be6d 100644
--- a/src/nvim/msgpack_rpc/helpers.h
+++ b/src/nvim/msgpack_rpc/helpers.h
@@ -9,6 +9,13 @@
 #include "nvim/event/wstream.h"
 #include "nvim/api/private/defs.h"
 
+/// Value by which objects represented as EXT type are shifted
+///
+/// Subtracted when packing, added when unpacking. Used to allow moving
+/// buffer/window/tabpage block inside ObjectType enum. This block yet cannot be
+/// split or reordered.
+#define EXT_OBJECT_TYPE_SHIFT kObjectTypeBuffer
+
 #ifdef INCLUDE_GENERATED_DECLARATIONS
 # include "msgpack_rpc/helpers.h.generated.h"
 #endif