How can I recover option values with the current l3keys2e?

Question

Minimal-Compiling-But-Not-Working Example:

\begin{filecontents}{\jobname.cls}

\ProvidesClass{\jobname}

\RequirePackage{l3keys2e}

\ExplSyntaxOn
\keys_define:nn { job / doc }
{
  doc~name .tl_set:N = \l_job_doc_name,
}

\ProcessKeysOptions { job / doc }

\ExplSyntaxOff

\PassOptionsToClass{10pt}{article}
\DeclareOption*{%
  \PassOptionsToClass{\CurrentOption}{article}
}
\ProcessOptions

\LoadClass{article}

\ExplSyntaxOn
\AtBeginDocument{
  This ~ document's ~ name ~ is ~ \l_job_doc_name .\par
}
\ExplSyntaxOff
\endinput
\end{filecontents}

\documentclass[doc name=ben]{\jobname}
\begin{document}
  hello
\end{document}

I would expect this to give me 'This document's name is ben.' then a new line, then 'hello'. However, that doesn't happen any longer, although (a much more complex version of) this code used to work.

Answer 1

Your problem is that the LaTeX kernel removes spaces from the global option list before it's passed to any further code. As such, l3keys2e sees docname=ben which is a different key name to doc name. The safest solution here is to not use spaces in key names.

Answer 2

Apparently, this is an intended change:

We used to normalise out spaces entirely, but there were some issues so that's been dropped. -- Joseph Wright

So the breakage is a new feature ;).

Since the problem is that the space is normalised away from the options passed to the class/package, but not the options defined in the class/package, I guess the easiest way to deal with the change to the code which l3keys2e sees is to remove the space in the class/package definition. The spaces in documents can be left, as they will be normalised away to match the key names in the package/class before the l3keys2e code sees them.

That is, I can write

 \keys_define:nn { job / doc }
{
  doc name .tl_set:N = \l_job_doc_name,
}

and then

\documentclass[doc name=ben]{\jobname}

will work as expected: in both cases, the space will disappear and everything will match up properly. So

\ProcessKeysOptions { job / doc }

will match docname with docname and l3keys2e will know my document is named ben.