MULTI/EXEC crashes inside PIPELINE

check_pipeline_multi.lua

pcall(require, 'luarocks.require')

local sidereal = require 'sidereal' -- sudo luarocks install sidereal --from=http://luarocks.org/repositories/rocks-cvs

--------------------------------------------------------------------------------
-- Some value printing code
--------------------------------------------------------------------------------

require 'lua-nucleo.module' -- sudo luarocks install lua-nucleo
require 'lua-nucleo.strict'

local tstr = import 'lua-nucleo/tstr.lua' { 'tstr' } -- Lua value to string

local N = 1
local P = function(...) print(N .. ":", tstr(assert(...))); N = N + 1 end

--------------------------------------------------------------------------------
-- Connect to Redis
--------------------------------------------------------------------------------

local R = assert(sidereal.connect("localhost", 6379))

--------------------------------------------------------------------------------
-- Fill data
--------------------------------------------------------------------------------

R:set("MYKEY", "value")

--------------------------------------------------------------------------------
-- This works
--------------------------------------------------------------------------------

P (R:multi())
--> 1: "OK"
P (R:get("MYKEY"))
--> 2: "QUEUED"
P (R:exec())
--> 3: "value"

--------------------------------------------------------------------------------
-- This does not
--------------------------------------------------------------------------------

R:pipeline()
P (R:multi())
--> 4: {}
P (R:get("MYKEY"))
--> 5: {}
P (R:exec())
-->
--[[
lua: /usr/local/share/lua/5.1//sidereal.lua:1062: handling multiple responses failed(2)
stack traceback:
	[C]: in function 'error'
	/usr/local/share/lua/5.1//sidereal.lua:1062: in function </usr/local/share/lua/5.1//sidereal.lua:1058>
	(tail call): ?
	check_pipeline_multi.lua:48: in main chunk
	[C]: ?
--]]
R:send_pipeline()

P (R:get_response())
--> (not reached)
P (R:get_response())
--> (not reached)
P (R:get_response())
--> (not reached)