From: Eli Zaretskii <eliz@gnu.org>
Date: Wed, 19 May 2021 16:01:07 +0000 (+0300)
Subject: Fix rare failures in 'window-default-font-height'
X-Git-Tag: emacs-28.0.90~2392
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=171dbe704890a16cb7381afd7461f6138481ade8;p=emacs.git

Fix rare failures in 'window-default-font-height'

* lisp/window.el (window-default-font-height): Avoid signaling an
error when a client TTY frame happens to have an X-style 'display'
parameter.  (Bug#48408)
---

diff --git a/lisp/window.el b/lisp/window.el
index 1c719480cab..0f94d8a2141 100644
--- a/lisp/window.el
+++ b/lisp/window.el
@@ -8788,7 +8788,11 @@ font on WINDOW's frame."
   (let* ((window (window-normalize-window window t))
 	 (frame (window-frame window))
 	 (default-font (face-font 'default frame)))
-    (if (and (display-multi-font-p (frame-parameter frame 'display))
+    ;; Client frames can have the 'display' parameter set like for X
+    ;; frames, even though they are TTY frames, so make sure we won't
+    ;; be duped by that up front with 'framep'.
+    (if (and (not (eq (framep frame) t))
+             (display-multi-font-p (frame-parameter frame 'display))
 	     (not (string-equal (frame-parameter frame 'font) default-font)))
         (aref (font-info default-font frame) 3)
       (frame-char-height frame))))