\input regression-test.tex
\documentclass{article}
% "load babel" without a "map": langselect resolves each selectable ISO code to
% a babel language name from babel-<code>.ini (de -> ngerman, en -> english),
% loads babel with those names, and selects the target.  csquotes autostyle
% must see a real babel name, not the bare code.
\usepackage[
  languages={en,de},
  targetlang=de,
  load babel
]{langselect}
\begin{document}
\START
\TYPE{target=\olsTargetLanguage}
\TYPE{active=\languagename}
\lende{English \enquote{q}}{Deutsch \enquote{q}}
\END
\end{document}