Function lua_pushvalue

third-party/lua-5.4.6/src/lapi.c:270–275

LUA_API void lua_pushvalue (lua_State *L, int idx) {
  lua_lock(L);
  setobj2s(L, L->top.p, index2value(L, idx));
  api_incr_top(L);
  lua_unlock(L);
}