bug#74833: 31.0.50; Copy to OS clipboard doesn't work in macOS Terminal.app with xterm-mouse-mode enabled

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 27 Dec 2024 23:08:27 -0800
> From: Jared Finder <jared@finder.org>
> Cc: shipmints@gmail.com, rms@gnu.org, gerd.moellmann@gmail.com,
>  fgunbin@fastmail.fm, 74833@debbugs.gnu.org
> 
> >> What if we only auto-enabled xterm-mouse-mode on OSC52 compatible
> >> terminals?
> > 
> > On OSC52 compatible terminals, or on OSC52 compatible terminals that
> > define TERM to xterm-like string?  The latter sounds like a good idea
> > to me, but only if support for OSC52 necessarily means xterm-mouse
> > escape sequences must be supported.  Is this conjecture indeed true?
> 
> I'm proposing Emacs have a manually curated allow list for now for 
> auto-enabling xterm-mouse-mode. Being OSC52 compatible gets us the copy 
> / paste issue this bug mentioned. We can add other conditions going 
> forward.

What would this allow list specify, and in what terms?

When reading your proposal above, I thought we have a means of testing
the OSC52 support, but now you seem to be saying that this support
should be somehow specified by a database of terminals we maintain?
ANd if so, the question of detecting a non-xterm terminal that sets
TERM to xterm but doesn't support OSC52 still stands, doesn't it?

> >> Between $TERM and the results from the terminal escape
> >> sequence "ESC [ > 0 q", Emacs can have high confidence if it is 
> >> running
> >> on an OSC52 compatible terminal. I checked against most of the 
> >> terminals
> >> mentioned at
> >> https://can-i-use-terminal.github.io/features/osc52copy.html I just
> >> wasn't able to test Foot (Wayland-only), hterm (Chromebook-only), 
> >> mintty
> >> (Cygwin-only), or xterm.js (I have no idea how to test).
> > 
> > How do I check this? can you show some script or Lisp or whatever you
> > used to check?
> 
> Run the following lisp code in Emacs:
> 
> (progn
>    (send-string-to-terminal "\e[>0q")
>    (let ((str "")
>          chr)
>      (while (setq chr (xterm--read-event-for-query))
>        (setq str (concat str (string chr))))
>      str))
> 
> You should get the string "\eP>|terminal name and version\e\\". For 
> example, under iTerm2 I get iTerm2 3.5.10 as the terminal name and 
> version and under Kitty I get kitty(0.38.1).

And if the terminal does NOT support OSC52, what should I expect to
happen?