hyperref links break with pdftex + babel + Hebrew (or right-to-left language)

Question

Using the babel package to write Hebrew text exposes incompatibilities with all sorts of other packages. This questions is about the incompatibility with hyperref.

Basically, you can't get links with right-to-left text. It's about the direction rather than the non-Latin language - somehow the link-start command is placed at the end due to some sort of reversal. The problem is described in Guy Rutenberg's blog, here.

Here's an MWEs for \cite and \ref:

\documentclass{article}
\usepackage[hebrew,english]{babel}
\usepackage{hyperref}
\begin{document}
\section{A section}
\label{mysection}
LTR English cite \cite{MYSRC}. And now in RTL Hebrew:

\selectlanguage{hebrew}
\cite{MYSRC}
\selectlanguage{english}

Let's refer to the current section:

\selectlanguage{hebrew}
\ref{mysection}

\begin{thebibliography}{MYSRC}
\bibitem[MYSRC01]{MYSRC}
The bibliography entry for MYSRC.
\end{thebibliography}
\end{document}

For both of these (and for \autoref), you get:

! pdfTeX error (ext4): pdf_link_stack empty, \pdfendlink used without \pdfstart
link?.
\AtBegShi@Output ...ipout \box \AtBeginShipoutBox 
                                                  \fi \fi 

Notes:

• Vafa Khaligi's comment below may be useful in isolating the minimum offending code out of everything 'babel' does, although I can't say for sure.
• The blog entry I linked to has a workaround - which only works with xetex. Can it be adapted somehow?
• Stefan Kottwitz suggested a workaround which won a bounty on this question. But what I would really like is to make hyperref get such links correctly somehow.

Answer 1

This is not an answer. I was able to produce the minimal working example as:

\documentclass{article}
\usepackage{hyperref}
\TeXXeTstate=1
\def\neweverypar{{\setbox0\lastbox\beginR\usebox0}}
\let\origeverypar=\everypar
\def\everypar#1{\origeverypar{\neweverypar#1}}
\begin{document}
This is \href{http://google.com}{Google} and ...
\end{document}

after runing pdflatex on this, you get exactly the same error message. I have also forwared this to Heiko Oberdiek and if he answers me, then I post his answer here but I think this actually seems to be a limitation of the pdfTeX engine with TeX--XeT algorithm (the algorithm already have many annoying bugs) and it may turn out that this is not even fixable. XeTeX and PDFTeX both uses TeX--XeT but hyperref with PDFTeX uses PDFTeX primitives for hypertext and in XeTeX, it uses \special.

Edit: This is verbatim response of Heiko Oberdiek:

I don't know. AFAIK there isn't even an easy way to test, whether \beginR or \beginL is active. A workaround could be to put two labels with some distance to find out the writing direction, thus that the order of \pdfstartlink and \pdfendlink could be switched if necessary. But that kind of workaround does not scale, the hash table size in TeX is limited, large document with many links will too easily hit the limit.

In LuaTeX the node lists can be examined and the switches can be done at Lua level.

I also asked him, why this problem happens with PDFTeX and not with XeTeX. Here is his response:

Perhaps the \specials are resorted automatically in xdvipdfmx.

Answer 2

use bidi package with xelatex. You can perhaps apply bidi changes to pdfTeX too (xetex and pdftex both use etex for bidi typesetting so there should not be a problem). I slightly changed your example to use polyglossia (hence using bidi):

\documentclass{article}
\usepackage{hyperref}
\usepackage{polyglossia}
\setmainlanguage{english}
\setotherlanguage{hebrew}
\newfontfamily\hebrewfont[Script=Hebrew]{Ezra SIL} % from SIL
\begin{document}
\section{A section}
\label{mysection}
LTR English reference \autoref{mysection}. And now in RTL Hebrew:

\begin{hebrew}
הוא פשוט טקסט גולמי של תעשיית ההדפסה וההקלדה. Lorem Ipsum היה טקסט סטנדרטי עוד במאה ה-16, כאשר הדפסה לא ידועה לקחה מגש של דפוס ועירבלה אותו כדי ליצור סוג של ספר דגימה. ספר זה שרד לא רק חמש מאות שנים אלא גם את הקפיצה לתוך ההדפסה
\autoref{mysection}
יש המון גרסאות זמינות לפסקאות של . אבל רובם עברו שינויים בצורה זו או אחרת, על ידי השתלת הומור או מילים אקראיות שלא נראות אפילו מעט אמינות. אם אתה הולך להשתמש במקטעים של של Lorem Ipsum אתה צריך להיות בטוח שאין משהו מביך חבוי בתוך 
\end{hebrew}
\end{document}

and the result is shown below:

Answer 3

hyperref provides commands for referencing without creating hyperlinks, such as \ref* and \autoref*.

Your example is compilable if I use \autoref*:

\selectlanguage{hebrew}
\autoref*{mysection}

You even could switch off hyperlinking for parts of the document, such as by

\makeatletter
\newcommand*{\disablehref}{%
  \let\ref\@refstar
  \DeclareRobustCommand*{\autoref}{\HyRef@autoref\@gobbletwo}}
\makeatother

Use it in a group or environment, to limit the effect, or create a similar macro \enablehref.

And here's a macro \disablehyperlinks, which works similar like the draft option of hyperref, disabling hyperlinks. So \autoref, \ref, \cite and \url work with Hebrew. Again, use it in a group or environment to limit the effect. Code and combined example:

\documentclass{article}
\usepackage[hebrew,english]{babel}
\usepackage{hyperref}
\makeatletter
\newcommand*{\disablehyperlinks}{
  % This is is for compatibility for hyperref versions 6.82d and older
  \@ifundefined{Hy@xspace@end}{
    \let\Hy@xspace@end\relax
  }{}
  \let\hyper@@anchor\@gobble
  \def\hyper@link##1##2##3{##3\Hy@xspace@end}%
  \def\hyper@anchorstart##1##2{##2\Hy@xspace@end}%
  \def\hyper@anchorend{\Hy@xspace@end}%
  \let\hyper@linkstart\@gobbletwo
  \def\hyper@linkend{\Hy@xspace@end}%
  \def\hyper@linkurl##1##2{##1\Hy@xspace@end}%
  \def\hyper@linkfile##1##2##3{##1\Hy@xspace@end}%
  \def\hyper@link@[##1]##2##3##4{##4\Hy@xspace@end}%
}
\makeatother
\begin{document}
\section{A section}
\label{mysection}
LTR English cite \cite{MYSRC} in \autoref{mysection} on \url{tex.stackexchange.com}.
And now in RTL Hebrew:

\begingroup
\disablehyperlinks
\selectlanguage{hebrew}
\cite{MYSRC}

\autoref{mysection}

\url{tex.stackexchange.com}

\endgroup
\selectlanguage{english}
Now again LTR English cite \cite{MYSRC} in \autoref{mysection} on
\url{tex.stackexchange.com}.
\begin{thebibliography}{MYSRC}
\bibitem[MYSRC01]{MYSRC}
The bibliography entry for MYSRC.
\end{thebibliography}
\end{document}