console: drop unused serpent module

Since the commit ae7e2103 we use internal serializer
thus we no longer need serpent code.

The patch removes the references from the source code
and .gitmodules file, still one might need to run

 | git submodule deinit -f third_party/serpent

manually to clean up the working tree depending
on local git version.

Closes #5517

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>

.gitmodules

@@ -34,9 +34,6 @@
 [submodule "third_party/decNumber"]
 	path = third_party/decNumber
 	url = https://github.com/tarantool/decNumber.git
-[submodule "third_party/serpent"]
-	path = third_party/serpent
-	url = https://github.com/tarantool/serpent.git
 [submodule "third_party/curl"]
 	path = third_party/curl
 	url = https://github.com/tarantool/curl.git

.luacheckrc

@@ -29,7 +29,6 @@ include_files = {
 exclude_files = {
     "build/**/*.lua",
     -- Third-party source code.
-    "src/box/lua/serpent.lua",
     "test-run/**/*.lua",
     "test/**/*.lua",
     "third_party/**/*.lua",

src/box/CMakeLists.txt

@@ -17,7 +17,6 @@ endif()
 lua_source(lua_sources lua/net_box.lua)
 lua_source(lua_sources lua/upgrade.lua)
 lua_source(lua_sources lua/console.lua)
-lua_source(lua_sources lua/serpent.lua)
 lua_source(lua_sources lua/xlog.lua)
 lua_source(lua_sources lua/key_def.lua)
 lua_source(lua_sources lua/merger.lua)

src/box/lua/console.c

@@ -48,8 +48,6 @@
 #include <stdlib.h>
 #include <ctype.h>
 
-extern char serpent_lua[];
-
 static struct luaL_serializer *serializer_yaml;
 static struct luaL_serializer *serializer_lua;
 
@@ -578,24 +576,6 @@ console_session_push(struct session *session, struct port *port)
 				     TIMEOUT_INFINITY);
 }
 
-static void
-lua_serpent_init(struct lua_State *L)
-{
-	static const char modname[] = "serpent";
-	const char *modfile;
-
-	lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
-	modfile = lua_pushfstring(L, "@builtin/%s.lua", modname);
-	if (luaL_loadbuffer(L, serpent_lua, strlen(serpent_lua), modfile)) {
-		panic("Error loading Lua module %s...: %s",
-		      modname, lua_tostring(L, -1));
-	}
-
-	lua_call(L, 0, 1);
-	lua_setfield(L, -3, modname);  /* _LOADED[modname] = new table */
-	lua_pop(L, 2);
-}
-
 void
 tarantool_lua_console_init(struct lua_State *L)
 {
@@ -663,12 +643,6 @@ tarantool_lua_console_init(struct lua_State *L)
 	};
 	session_vtab_registry[SESSION_TYPE_CONSOLE] = console_session_vtab;
 	session_vtab_registry[SESSION_TYPE_REPL] = console_session_vtab;
-
-	/*
-	 * Register serpent serializer as we
-	 * need it inside console REPL mode.
-	 */
-	lua_serpent_init(L);
 }
 
 /*

src/box/lua/serpent.lua

-../../../third_party/serpent/src/serpent.lua
\ No newline at end of file

serpent @ 879580fb

-Subproject commit 879580fb21933f63eb23ece7d60ba2349a8d2848