%% test-latex-show.tex
%% ===================
%% Patch-status check for pdfLaTeX/LuaLaTeX/XeLaTeX (inspect the log,
%% not the typeset output).
%%
%%   pdflatex -interaction=nonstopmode test-latex-show.tex
%%   (or lualatex / xelatex)
%%
%% What to check in the log:
%%   * footnotenosplit-latex is loaded.
%%   * The build/column/before hook (shown by \LogHook) contains the
%%     code chunk calling \fns@discard@emptyfootins.
%%   * The \meaning after ===FOOTNOTETEXT=== contains
%%       \splittopskip \dimexpr \footnotesep +\footnotetopkern
%%   * ===IFP===10000 (\interfootnotelinepenalty=\@M)
%%   * No "Failed to patch" warnings.
\documentclass{book}
\usepackage{footnotenosplit}
\begin{document}
\makeatletter
\typeout{===FOOTNOTETEXT===^^J\meaning\@footnotetext^^J===IFP===\the\interfootnotelinepenalty===END===}
\makeatother
\LogHook{build/column/before}
test\footnote{footnote}
\end{document}