Bug: ob-R.el breaks when :session is specified

[Christian Heinrich <com-orgmode-mailinglist@gladbachcity.de>]

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Hi there,

I got back to an org file after upgrading to the latest release of org-mode and tried executing the
contained R source blocks. Unfortunately, emacs got stuck in the execution and was blocked; I had to
exit using C-g.

Here's a minimal example src block that causes emacs to get stuck:

#+begin_src R :results output :session *R* :exports both
  a <- 10
  a
#+end_src

R itself does start and the code is also executed correctly. However, the output from that session
is apparently not returned to emacs or the buffer.

When removing the :session argument it executes and returns as expected.

When bisecting this issue, I found that this commit causes it:
ac8c009e006197d2dad226dbe822d450aec23d23

    lisp/ob-R.el: Fix session output with substrings matching prompts

Reverting it fixes the issue for earlier release (9.5.3) as well as for the current main branch.

The (with-current-buffer session ... ) somehow seems to break it for me, but I am unsure why no one
else here seems to experience this as the commit is from 2020?

Any suggestions?

Thanks!
Christian

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