lua: vim.rpcrequest, vim.rpcnotify, vim.NIL

4 files changed, 124 insertions, 2 deletions

diff --git a/src/nvim/lua/converter.c b/src/nvim/lua/converter.c
index 844232c64a..44fe60e9c8 100644
--- a/src/nvim/lua/converter.c
+++ b/src/nvim/lua/converter.c
@@ -377,6 +377,19 @@ bool nlua_pop_typval(lua_State *lstate, typval_T *ret_tv)
 nlua_pop_typval_table_processing_end:
         break;
       }
+      case LUA_TUSERDATA: {
+        nlua_pushref(lstate, nlua_nil_ref);
+        bool is_nil = lua_rawequal(lstate, -2, -1);
+        lua_pop(lstate, 1);
+        if (is_nil) {
+          cur.tv->v_type = VAR_SPECIAL;
+          cur.tv->vval.v_special = kSpecialVarNull;
+        } else {
+          EMSG(_("E5101: Cannot convert given lua type"));
+          ret = false;
+        }
+        break;
+      }
       default: {
         EMSG(_("E5101: Cannot convert given lua type"));
         ret = false;
@@ -406,7 +419,13 @@ static bool typval_conv_special = false;
 #define TYPVAL_ENCODE_ALLOW_SPECIALS true
 
 #define TYPVAL_ENCODE_CONV_NIL(tv) \
-    lua_pushnil(lstate)
+    do { \
+      if (typval_conv_special) { \
+        lua_pushnil(lstate); \
+      } else { \
+        nlua_pushref(lstate, nlua_nil_ref); \
+      } \
+    } while (0)
 
 #define TYPVAL_ENCODE_CONV_BOOL(tv, num) \
     lua_pushboolean(lstate, (bool)(num))
@@ -718,7 +737,11 @@ void nlua_push_Object(lua_State *lstate, const Object obj, bool special)
 {
   switch (obj.type) {
     case kObjectTypeNil: {
-      lua_pushnil(lstate);
+      if (special) {
+        lua_pushnil(lstate);
+      } else {
+        nlua_pushref(lstate, nlua_nil_ref);
+      }
       break;
     }
     case kObjectTypeLuaRef: {
@@ -1152,6 +1175,19 @@ Object nlua_pop_Object(lua_State *const lstate, bool ref, Error *const err)
         break;
       }
 
+      case LUA_TUSERDATA: {
+        nlua_pushref(lstate, nlua_nil_ref);
+        bool is_nil = lua_rawequal(lstate, -2, -1);
+        lua_pop(lstate, 1);
+        if (is_nil) {
+          *cur.obj = NIL;
+        } else {
+          api_set_error(err, kErrorTypeValidation,
+                        "Cannot convert userdata");
+        }
+        break;
+      }
+
       default: {
 type_error:
         api_set_error(err, kErrorTypeValidation,
diff --git a/src/nvim/lua/executor.c b/src/nvim/lua/executor.c
index c7ff163f83..5e5cb0cea5 100644
--- a/src/nvim/lua/executor.c
+++ b/src/nvim/lua/executor.c
@@ -12,6 +12,7 @@
 #include "nvim/api/private/defs.h"
 #include "nvim/api/private/helpers.h"
 #include "nvim/api/vim.h"
+#include "nvim/msgpack_rpc/channel.h"
 #include "nvim/vim.h"
 #include "nvim/ex_getln.h"
 #include "nvim/ex_cmds2.h"
@@ -299,6 +300,14 @@ static int nlua_state_init(lua_State *const lstate) FUNC_ATTR_NONNULL_ALL
   lua_pushcfunction(lstate, &nlua_call);
   lua_setfield(lstate, -2, "call");
 
+  // rpcrequest
+  lua_pushcfunction(lstate, &nlua_rpcrequest);
+  lua_setfield(lstate, -2, "rpcrequest");
+
+  // rpcnotify
+  lua_pushcfunction(lstate, &nlua_rpcnotify);
+  lua_setfield(lstate, -2, "rpcnotify");
+
   // vim.loop
   luv_set_loop(lstate, &main_loop.uv);
   luv_set_callback(lstate, nlua_luv_cfpcall);
@@ -314,6 +323,15 @@ static int nlua_state_init(lua_State *const lstate) FUNC_ATTR_NONNULL_ALL
   lua_setfield(lstate, -2, "luv");
   lua_pop(lstate, 3);
 
+  // vim.NIL
+  lua_newuserdata(lstate, 0);
+  lua_createtable(lstate, 0, 0);
+  lua_pushcfunction(lstate, &nlua_nil_tostring);
+  lua_setfield(lstate, -2, "__tostring");
+  lua_setmetatable(lstate, -2);
+  nlua_nil_ref = nlua_ref(lstate, -1);
+  lua_setfield(lstate, -2, "NIL");
+
   // internal vim._treesitter... API
   nlua_add_treesitter(lstate);
 
@@ -547,6 +565,10 @@ int nlua_call(lua_State *lstate)
   Error err = ERROR_INIT;
   size_t name_len;
   const char_u *name = (const char_u *)luaL_checklstring(lstate, 1, &name_len);
+  if (!nlua_is_deferred_safe(lstate)) {
+    return luaL_error(lstate, e_luv_api_disabled, "vimL function");
+  }
+
   int nargs = lua_gettop(lstate)-1;
   if (nargs > MAX_FUNC_ARGS) {
     return luaL_error(lstate, "Function called with too many arguments");
@@ -596,6 +618,67 @@ free_vim_args:
   return 1;
 }
 
+static int nlua_rpcrequest(lua_State *lstate)
+{
+  if (!nlua_is_deferred_safe(lstate)) {
+    return luaL_error(lstate, e_luv_api_disabled, "rpcrequest");
+  }
+  return nlua_rpc(lstate, true);
+}
+
+static int nlua_rpcnotify(lua_State *lstate)
+{
+  return nlua_rpc(lstate, false);
+}
+
+static int nlua_rpc(lua_State *lstate, bool request)
+{
+  size_t name_len;
+  uint64_t chan_id = (uint64_t)luaL_checkinteger(lstate, 1);
+  const char *name = luaL_checklstring(lstate, 2, &name_len);
+  int nargs = lua_gettop(lstate)-2;
+  Error err = ERROR_INIT;
+  Array args = ARRAY_DICT_INIT;
+
+  for (int i = 0; i < nargs; i++) {
+    lua_pushvalue(lstate, (int)i+3);
+    ADD(args, nlua_pop_Object(lstate, false, &err));
+    if (ERROR_SET(&err)) {
+      api_free_array(args);
+      goto check_err;
+    }
+  }
+
+  if (request) {
+    Object result = rpc_send_call(chan_id, name, args, &err);
+    if (!ERROR_SET(&err)) {
+      nlua_push_Object(lstate, result, false);
+      api_free_object(result);
+    }
+  } else {
+    if (!rpc_send_event(chan_id, name, args)) {
+      api_set_error(&err, kErrorTypeValidation,
+                    "Invalid channel: %"PRIu64, chan_id);
+    }
+  }
+
+check_err:
+  if (ERROR_SET(&err)) {
+    lua_pushstring(lstate, err.msg);
+    api_clear_error(&err);
+    return lua_error(lstate);
+  }
+
+  return request ? 1 : 0;
+}
+
+static int nlua_nil_tostring(lua_State *lstate)
+{
+  lua_pushstring(lstate, "vim.NIL");
+  return 1;
+}
+
+
 #ifdef WIN32
 /// os.getenv: override os.getenv to maintain coherency. #9681
 ///
diff --git a/src/nvim/lua/executor.h b/src/nvim/lua/executor.h
index 8d356a5600..32f66b629c 100644
--- a/src/nvim/lua/executor.h
+++ b/src/nvim/lua/executor.h
@@ -12,6 +12,8 @@
 // Generated by msgpack-gen.lua
 void nlua_add_api_functions(lua_State *lstate) REAL_FATTR_NONNULL_ALL;
 
+EXTERN LuaRef nlua_nil_ref INIT(= LUA_NOREF);
+
 #define set_api_error(s, err) \
     do { \
       Error *err_ = (err); \
diff --git a/src/nvim/main.c b/src/nvim/main.c
index e0a1e60fc0..e39eec4038 100644
--- a/src/nvim/main.c
+++ b/src/nvim/main.c
@@ -27,6 +27,7 @@
 #include "nvim/highlight.h"
 #include "nvim/iconv.h"
 #include "nvim/if_cscope.h"
+#include "nvim/lua/executor.h"
 #ifdef HAVE_LOCALE_H
 # include <locale.h>
 #endif