%% test-nojapanese.tex
%% ===================
%% Without pTeX or LuaTeX-ja (pdfLaTeX, XeLaTeX, or LuaLaTeX without
%% LuaTeX-ja), the package warns and does nothing.
%%
%%   pdflatex test-nojapanese.tex
%%
%% What to check:
%%   * The warning "Neither pTeX nor LuaTeX-ja found" and no error.
\documentclass{article}
\usepackage{showhanmengrid}
\begin{document}
Text.
\end{document}