Subject: bug#77328: 31.0.50; eglot-code-action-indicator containing U+F400

From: Gerd Möllmann <[email-masked]>
Date: Fri, 28 Mar 2025 07:07:08 +0100

In master

eglot.el:
  614 (defcustom eglot-code-action-indicator
  615   (cl-loop for c in '(? ?⚡?✓ ?α ??)
  616            when (char-displayable-p c)
  617            return (make-string 1 c))

The first character checked above is

             position: 28703 of 217477 (13%), column: 23
            character:  (displayed as ) (codepoint 62464, #o172000, #xf400)
              charset: unicode (Unicode (ISO10646))
code point in charset: 0xF400
               syntax: w 	which means: word
             category: L:Strong L2R
             to input: type "C-x 8 RET f400"
          buffer code: #xEF #x90 #x80
            file code: #xEF #x90 #x80 (encoded by coding system utf-8-unix)
              display: terminal code #xEF #x90 #x80

which is a character in a "private use area". I guess that could
indicate that the use of this character is maybe not intentional.

(In my setting, macOS/iTerm2 terminal, JetBrains MONO font, running
emacs -nw, char-displayable-p returns t for #xf400, and it is displayed
as a question mark in a box, which is otherwise used for characters with
no defined meaning.)