# MiKTeX 2.9, latest package update broke biblatex bibliography

I have strange problem with bibliography after the latest MiKTeX 2.9 base packages update. In the document I use biblatex package with backend option either bibtex8 or biber.

Before, bibliography was printed in the end and had its own chapter with title Bibliography, and with an entry in TOC, etc. Now, bibliography is printed, but without chapter title - it is simply blank. TOC entry is missing as well.

Citations are also broken. Before, if my bib file entry had an article with 2 authors, and when I cited it, it was printed as Albert and Chib (1993), for example. Now, and is missing, and it simply prints Albert (space) Chib (1993). Note, that (space) is not printed, I put it there because StackExchange formats the message.

What is going on here?
How can I fix such things?

You can reproduce the issue by installing MikTeX 2.9, update packages through maintenance, and then produce any PDF with bibliography. I tested it in 2 workstations - the result is the same. In one workstation I had outdated MikTeX without latest updates, and when I typeset a document it was fine. Then, I installed updates and typeset again, and it became "broken".

MWE:

\documentclass[a4paper,12pt,oneside,titlepage]{report}
\usepackage[natbib = false,
backend = bibtex8,
style = authoryear,
maxcitenames = 2,
mincitenames = 1,
maxbibnames = 100
]{biblatex}

\begin{document}
\title{Some title}
\author{Oleksandr Dyklevych}
\date{\today} %\May 7, 2012
\maketitle

\tableofcontents

\chapter{Introduction} \label{ch:Intro}
Bla~\cite{Albert1993}.

\printbibliography

\end{document}


SomeBib.bib file content:

@Article{Albert1993,
title = "Bayesian Analysis of Binary and Polychotomous Response Data",
author = "Albert, James H. and Chib, Siddhartha",
journal = "Journal of the American Statistical Association",
volume = "88",
number = "422",
date = "1993-07",
pages = "669--679",
url = "http://www.jstor.org/stable/2290350",
}


Added: The full list of the updated packages during the last update: xetex-def, tools, ltxbase, miktex-misc, graphics, bidi. So, one of them must be causing the problem.

-
Please provide a MWE so that it is possible to replicate this error. Maybe some package is introducing this behaviour. –  Rüdiger Voigt May 8 at 7:19
I provided MWE. As you can see, no other package is used. It is MikTeX base packages problem, I think. –  Oleksandr May 8 at 7:29
I have problems too (with languages). It's the keyval package which brakes everythings. It's handling of braces has changed. With the old keyval.sty everything works. As a workaround: try to load xkeyval before biblatex. –  Ulrike Fischer May 8 at 8:05
@UlrikeFischer, yes, that works! If you post it as answer I'll accept it. –  Oleksandr May 8 at 8:18

I have problems too (with languages). It's the update of the keyval package which breaks everythings. Its handling of braces around arguments has changed. With the old keyval.sty everything works. As a workaround: try to load xkeyval before biblatex.

As one can read in ltnews21.pdf the change in braces handling in intentional:

All parsing used in the keyval package has been changed to allow \par (and blank lines) in values. Also only one rather than two levels of brace groups are now stripped from the value in a construct such as key={{{value}}}.
See graphics/3446.

I have sent a message to the latex3 mailing list that it affects biblatex so heavily. I will also inform the biblatex maintainers.

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yes thanks for the heads up, will report back.... –  David Carlisle May 8 at 9:15
There is a xkeyval update on CTAN which problably will lead to the same problems. It hasn't hit miktex yet but it when it will you should better refuse the update until it is clear that the problem is solved. –  Ulrike Fischer May 8 at 9:40
Note that the quote from LTnews isn't strictly relevant other than to note that the code has changed. The change to strip one rather than two brace groups would not affect biblatex. It just moved a bug that was arguably in keyval from the start but masked, into a form where it does affect biblatex. A fix is being investigated. –  David Carlisle May 8 at 10:43
sorry about that. A new keyval.dtx (v1.15) has been submitted to ctan, it will take a while to propagate to ctan mirrors and tex distributions. It reverts the change to {} parsing. The quoted paragraph in ltnews21 has been adjusted. –  David Carlisle May 8 at 21:51