How do I use glyphtounicode to make Caslon Pro ligatures searchable?

Question

I am using Adobe Caslon Pro with a caslon.sty file which activates uncommon ligatures such as st, ct, longsl, longst &c. I use it in the following example (updated to match the answer in the comment below):

\documentclass[english]{book}
\usepackage[T1]{fontenc}
\input{glyphtounicode}
\pdfglyphtounicode{germandbls}{0073 0073} % Override: normally eszet does not match “ss”
% Extra Unicode characters
\pdfglyphtounicode{longst}{FB05}
\pdfglyphtounicode{st}{FB06} % This is not produced by caslon.sty
% Ligatures with no Unicode characters
\pdfglyphtounicode{longdbls}{0073 0073}
\pdfglyphtounicode{ct}{0063 0074}
\pdfglyphtounicode{longsh}{0068 0074}
\pdfglyphtounicode{longsi}{0069 0074}
\pdfglyphtounicode{longsl}{006c 0074}
\pdfgentounicode=1
\usepackage[longs]{caslon}
\begin{document}
Goose taste has hash sin slim fact passing pass past.
\end{document}

Unfortunately, I can no longer find the caslon.sty that I use online, nor do the files give any clue as to their authorship. (There are a few different Adobe Caslon Pro support files for LaTeX, in CTAN and other places, but none seems to support the extra ligatures.) Hence, I've put a Zip bundle online at:

http://rrt.adsensus.net/acaslon.zip

of the files exactly as I downloaded them.

Answer 1

This is easy if you use lualatex in the command line instead of pdflatex.

\documentclass[english]{book}
\usepackage{fontspec}
\setmainfont[Style = {Historic}] {ACaslonPro}
\begin{document}
In goose taste.
\end{document}

Is lualatex an option you could try?