bug#41372: 28.0.50; [PATCH] Wrong value of tab-bar-tab-name-ellipsis

[Matthias Meulien]

When I evaluate (char-displayable-p ?…) from current frame (under X) it
evaluates to a valid font but, after I customized
`tab-bar-tab-name-function` to equal `tab-bar-tab-name-truncated`, tab
names are truncated using three dots characters.

>From 6482236257c99dcd411d635360ce4c1d8144b3f0 Mon Sep 17 00:00:00 2001
From: Matthias Meulien <orontee@gmail.com>
Date: Mon, 18 May 2020 00:32:47 +0200
Subject: [PATCH] Fix tab-bar-tab-name-ellipsis initialization

* lisp/tab-bar.el (tab-bar-tab-name-truncated): Evaluate displayable
character when generating tab name.
---
 lisp/tab-bar.el | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index ce6d8c33dd..c327ac0967 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -376,19 +376,16 @@ tab-bar-tab-name-truncated-max
   :group 'tab-bar
   :version "27.1")
 
-(defvar tab-bar-tab-name-ellipsis
-  (if (char-displayable-p ?…) "…" "..."))
-
 (defun tab-bar-tab-name-truncated ()
   "Generate tab name from the buffer of the selected window.
-Truncate it to the length specified by `tab-bar-tab-name-truncated-max'.
-Append ellipsis `tab-bar-tab-name-ellipsis' in this case."
-  (let ((tab-name (buffer-name (window-buffer (minibuffer-selected-window)))))
+Truncate it to the length specified by `tab-bar-tab-name-truncated-max'."
+  (let ((tab-name (buffer-name (window-buffer (minibuffer-selected-window))))
+        (ellipsis (if (char-displayable-p ?…) "…" "...")))
     (if (< (length tab-name) tab-bar-tab-name-truncated-max)
         tab-name
       (propertize (truncate-string-to-width
                    tab-name tab-bar-tab-name-truncated-max nil nil
-                   tab-bar-tab-name-ellipsis)
+                   ellipsis)
                   'help-echo tab-name))))
 

-- 
2.20.1



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