%#!luajitlatex
\directlua{luatexja_debug=1}
\documentclass{ltjsarticle}

\def\showdir{{\fboxsep1pt\fbox{\sf \ifydir Y\fi\iftdir T\fi\ifddir D\fi}}}
\begin{document}
\hsize=100mm\vsize=100mm
あいうえお\insert\footins{\tate TATE}\showdir\insert\footins{\yoko YOKO2}
\typeout{FUGA}

\vbox{\tate
\the\globaldefs まみむ\showdir

  \hbox{\yoko ABCあいう\showdir
    \vadjust{insertion感じ\showdir
      \hbox{\dtou hboxあいう\showdir}
    }
  }

かきくけこ\typeout{HOGE}\vadjust{insertion\showdir}
\vadjust{}
{\nonstopmode\vadjust{\yoko ins感じ\showdir}}
}


\end{document}