[luatex] luatexbase.add_to_callback does not preserve the order

[David Carlisle]

I put a comment in github but I think that this fixes the issue (using
ipairs rather than pairs in add_to_callback so the list is constituted
in the right order)  Below I redefine add_to_callback in the test file
but if you locally edit luatexbase.sty with that definition and could
confirm it works on your original files, we will push an update to
ctan, thanks again.



\batchmode
\input luatexbase.sty
\directlua{
function luatexbase.add_to_callback(name,fun,description,priority)
  local priority= priority
  local len=\string#luatexbase.callback_descriptions(name)
  if (priority==nil) then
   priority=len+1
  end
  if(luatexbase.callbacktypes[name] == 3 and
     priority == 1 and
     len==1) then
    luatexbase.module_warning("luatexbase",
                              "resetting exclusive callback: " .. name)
    luatexbase.reset_callback(name)
  end
  local saved_callback={},ff,dd
  for k,v in ipairs(luatexbase.callback_descriptions(name)) do
    if k >= priority then
      ff,dd= luatexbase.remove_from_callback(name, v)
      saved_callback[1+k-priority]={ff,dd}
    end
  end
  luatexbase.base_add_to_callback(name,fun,description)
  for k,v in ipairs(saved_callback) do
    luatexbase.base_add_to_callback(name,v[1],v[2])
  end
  return
end
}
\scrollmode\catcode`\_=12

\directlua{
  luatexbase.create_callback('test', 'data', function(n) return n end)
  local fn = {}
  for n=1,20 do
    fn[n] = function()
      texio.write(tostring(n) .. ', '); return 1
    end
    luatexbase.add_to_callback('test', fn[n], n, n)
  end
  luatexbase.call_callback('test', 0)
  texio.write_nl('')
  for i=1,300 do
    local n = math.random(20)
    luatexbase.remove_from_callback('test', n) % remove fn[n]
    luatexbase.add_to_callback('test', fn[n], n, n)
  end
  texio.write_nl('')
  luatexbase.call_callback('test', 0)
}

\batchmode\bye