* lisp/emacs-lisp/warnings.el (display-warning): Add guardrails for window.

Check for non-nil 'window' returned from 'display-buffer' for the case when
users decide to use 'allow-no-window' in 'display-buffer-alist' (#70795).

(cherry picked from commit 446031722546513ace2dc6f3ee86999bb7e17b39)

diff --git a/lisp/emacs-lisp/warnings.el b/lisp/emacs-lisp/warnings.el
index 8c1e43934ff565e0085254266fe4f0f0b93a3916..68db33bfa68dd6b0e088d7e2a7bf11df77aa57f0 100644 (file)
--- a/lisp/emacs-lisp/warnings.el
+++ b/lisp/emacs-lisp/warnings.el
@@ -377,10 +377,10 @@ entirely by setting `warning-suppress-types' or
                                        (window-height . (lambda (window)
                                          (fit-window-to-buffer window 10)))
                                        (category . warning))))))
-                      (when (and (markerp warning-series)
+                      (when (and window (markerp warning-series)
                                  (eq (marker-buffer warning-series) buffer))
                         (set-window-start window warning-series))
-                      (when warning-display-at-bottom
+                      (when (and window warning-display-at-bottom)
                         (with-selected-window window
                           (goto-char (point-max))
                           (forward-line -1)