# tabu: Error since update

Since the last update of tabu.sty I get the following error:

! Improper \prevdepth. \tabu@verticalspacing ... tempdimc \t


Here is a MWE

\documentclass[a4paper,12pt]{report}
\usepackage{tabu}
\usepackage{amsmath}
\usepackage{xcolor}
\newcolumntype{L}{>{\begin{varwidth}{0.91\linewidth}}l<{\end{varwidth}}}

\begin{document}
\begin{tabu}{Lcc}
$\begin{pmatrix} 1 \\2\\3 \end{pmatrix}$& 2& 3\\
\end{tabu}

\end{document}


The error occurs, when including pmatrix (or array) in a tabu-environment with a predefined column (using varwidth) AND strangely when including any other of a list of packages (like: color.sty, xcolor.sty, pstricks-add.sty, colortbl.sty, ...) Everything worked fine before the update!

Does anyone know, how to fix this?

Here is the first line of the log file:

This is pdfTeX, Version 3.14159265-2.6-1.40.19 (MiKTeX 2.9.6930 64-bit) (preloaded format=latex 2019.1.13) 20 JAN 2019 12:55 entering extended mode

I think this is the correct fix, if it survives some more testing I'll get tabu updated on ctan.

\documentclass[a4paper,12pt]{report}
\usepackage{tabu}
\usepackage{amsmath}
\usepackage{xcolor}
\newcolumntype{L}{>{\begin{varwidth}{0.91\linewidth}}l<{\end{varwidth}}}

\makeatletter
\def\tabu@verticalmeasure{\everypar{}%
\unless\ifnum\currentgrouptype=14 \let\tabu@currentgrouptype\currentgrouptype\fi
\ifnum \tabu@currentgrouptype>12         % 14=semi-simple, 15=math shift group
\setbox\tabu@box =\hbox\bgroup
\let\tabu@verticalspacing \tabu@verticalsp@lcr
\d@llarbegin                % after \hbox ...
\else
\edef\tabu@temp{\ifnum\tabu@currentgrouptype=5\vtop
\else\ifnum\tabu@currentgrouptype=12\vcenter
\else\vbox\fi\fi}%
\setbox\tabu@box \hbox\bgroup$\tabu@temp \bgroup \let\tabu@verticalspacing \tabu@verticalsp@pmb \fi } \makeatother \begin{document} \begin{tabu}{Lcc}$\begin{pmatrix}
1 \\2\\3
\end{pmatrix}$& 2& 3\\ \end{tabu} \end{document}  • As far as I can test it right now, it works. Although the$ in the line \setbox\tabu@box \hbox\bgroup\$\tabu@temp \bgroup confuses my editor, because it sees it as a beginning of a formular. – chris Jan 20 at 13:43
• @chris thanks I plan to push 2.10 to ctan now, so it should appear in texlive/miktex later in the week. – David Carlisle Jan 20 at 13:50
• Thanks! However, I just found out, the above mentioned problem also occurs (exactly in the same way), when including a table (e.g tabular) in the tabu-environment and is not solved by this solution. (It also worked before the last update!) – chris Jan 20 at 14:06