[ESS] ess-mode [elpa: 25.1.0]; ESS doesn't respect R_HISTFILE and R_HISTSIZE

[Anush V]

Hello ESS maintainers,


I’ve noticed that ESS requires setting comint-input-ring-size,
ess-history-file, and ess-history-directory for managing R command
history.  However, I believe ESS should also respect R’s native
environment variables, R_HISTFILE and R_HISTSIZE, for consistency with
R’s default behavior.

I came across a related discussion from 2009
(https://stat.ethz.ch/pipermail/ess-help/2009-September/005555.html). The
R documentation
(https://search.r-project.org/R/refmans/utils/html/savehistory.html)
confirms that these variables control history handling in R.

Would it be possible to align ESS with R’s built-in history
management?  This could either be treated as a bug fix (if
unintentional) or a feature request (if a deliberate design choice).

Thank you for your time and for maintaining ESS.  It’s an invaluable
tool for GNU R users!

Emacs  : GNU Emacs 30.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.43, cairo version 1.18.2)
Package: ess-mode  [elpa: 25.1.0]

--
Regards,
Anush Veeranala