Re: master 18b680cfd1: Fix bug#52467 by adding a new custom variable 'display-comint-buffer-action'

[martin rudalics]

> Martin's opinions are more relevant, I think.

Sorry, but I simply don't understand what's going on here.  Sam
Steingold's original report starts with the following statement:

  I would like to request reverting of the patch

  70b64e0d040e9c57f1a489c9ebee553264033119 "Use pop-to-buffer-same-window for 
shell"

  When I already have a window with shell, this patch creates a second
  such window.
  It seems much more reasonable to use pop-to-buffer in eshell rather than
  break shell's behavior.

  If you insist on your desired behavior, please add a user variable
  `shell-pop-to-buffer-action` that you would set to
  `display-buffer--same-window-action`.

Now IIUC the original code had 'pop-to-buffer' which conceptually does
create a new window.  'pop-to-buffer-same-window' OTOH conceptually
reuses the same window instead.  So how that patch could provoke this
behavior

  When I already have a window with shell, this patch creates a second
  such window.

is beyond my understanding.

Personally, I would not have installed the patch above because it
changes long-standing default behavior.  Users can always request
displaying eshell in the same window via 'display-buffer-alist'.  But
the bug report itself yet remains a mystery to me.

> Me, I think we have way too many display-buffer customization
> machinery, so much so that we are confused ourselves what we have and
> what we don't.  But if others think this particular addition could be
> useful, I don't mind: a defcustom doesn't by itself do any harm,
> except perhaps making Emacs a tad more complex.

If such a 'defcustom' does not affect a user's customizations via
'display-buffer-alist' I agree.  But if a user is then forced to use
that defcustom _instead of_ customizing 'display-buffer-alist', it would
do harm IMHO.

martin