bug#33992: 27.0.50; xref-find-definitions wastes too much space

[Juri Linkov]

>> A patch is proposed in a separate bug#35737.

I'm closing this request because now xref is customizable enough.
And we have no more opinions for changing the default behavior.

FWIW, this is what I currently use to customize xref-find-definitions
to act more like Completions:

(custom-set-variables
 '(display-buffer-alist
   '((display-buffer-to-xref-p display-buffer-in-direction
                               (direction . below)
                               (window-height . fit-window-to-buffer)))))

(defun display-buffer-to-xref-p (buffer-name _action)
  (and (string-match-p "\\`\\*\\(xref\\)\\*\\(\\|<[0-9]+>\\)\\'"
                       buffer-name)
       (memq this-command '(xref-find-definitions))))

(with-eval-after-load 'xref
  (defvar xref--original-command nil)
  (advice-add 'xref-find-definitions :after
              (lambda (&rest _args)
                (with-current-buffer (window-buffer)
                  (setq-local xref--original-command 'xref-find-definitions))))
  (define-key xref--button-map [(control ?m)]
    (lambda ()
      (interactive)
      (if (memq xref--original-command '(xref-find-definitions))
          (call-interactively 'xref-quit-and-goto-xref)
        (setq xref--original-window nil)
        (call-interactively 'xref-goto-xref)))))