I’m the maintainer of the nodetree package. I got a bug report: https://github.com/Josef-Friedrich/nodetree/issues/46
I was able to narrow down the problem:
debug.tex:
\documentclass{article}
\begin{document}
\directlua{
luatexbase.add_to_callback('vpack_filter',
function(head)
if node.type(head.id) == 'whatsit' and head.subtype == 1 then
local tmp = head.data
end
return true
end,
'debug'
)
}
\begin{figure}
\caption{test}
\end{figure}
\end{document}
lualatex debug.tex:
! Incomplete \iffalse; all text was ignored after line 19.
<inserted text>
\fi
l.19 \end{figure}
The line 'local tmp = head.data' causes the error. I tried also 'print(head.data)' or 'local tmp = head['data']'. These access types also caused a crash.
Access to fields other than data works without any problems.
print(head.stream)
print(head.id)
print(head.xxx)
Is this a bug in LuaTeX? Or how can I access the field 'data' of a whatsit(write) node for debugging purposes?
