cleveref and lineno

Question

How can I get cleveref to work with \linelabel from lineno?

\documentclass{article}



\usepackage{lineno}
\usepackage{cleveref}



\begin{document}
\linenumbers

Bla bla bla  bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla \linelabel{foo}  bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla

\cref{foo} doesn't work because the cleveref line doesn't get written to the aux file, but \ref{foo} works.
\end{document}

Answer 1

This is a quick hack, using \@LN@linelabel which does the line labelling.

First I use the old version of the command, extract the label value again, then set a backup counter, set linenumber to the label value, decrease it and step it again to get the correct \cref@currentlabel and then write label directly as cleveref would do.

\documentclass{article}
\usepackage{refcount}


\usepackage{lineno}
\usepackage{cleveref}

\newcounter{backuplineno}

\crefname{linenumber}{linenumber}{linenumbers}
\Crefname{linenumber}{Linenumber}{Linenumbers}



\makeatletter
\let\@LN@linelabelorig\@LN@linelabel
\renewcommand{\@LN@linelabel}[1]{%
  \@LN@linelabelorig{#1}%
  \IfRefUndefinedExpandable{#1}{}{%
    \setcounter{backuplineno}{\value{linenumber}}
    \addtocounter{linenumber}{-1}%
    \setcounter{linenumber}{\numexpr\getrefnumber{#1} -1}
    \refstepcounter{linenumber}%
    \protected@write\@auxout{}%
    {\string\newlabel{#1@cref}{{\cref@currentlabel}{\thepage}}}%
    \setcounter{linenumber}{\value{backuplineno}}
  }%
}
\makeatother

\begin{document}
\linenumbers

Bla bla bla  bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla \linelabel{foo}  bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla bla

\cref{foo} doesn't work because the cleveref line doesn't get written to the aux file, but \ref{foo} works.
\end{document}