emacs-29 f1032bf24e: Eglot: don't use "nil" as minibuffer initial input

[Eli Zaretskii]

branch: emacs-29
commit f1032bf24e79cf32341473c5d9f447c4c74f9d2b
Author: Eshel Yaron <me@eshelyaron.com>
Commit: Eli Zaretskii <eliz@gnu.org>

    Eglot: don't use "nil" as minibuffer initial input
    
    Doing M-x eglot in a buffer for which buffer-file-name is nil, prompts
    the user for a major mode to manage by invoking completing-read.  The
    way completing-read was called would end up with the string "nil" as
    the initial minibuffer input, which is not very useful nor is it a
    valid input.
    * lisp/progmodes/eglot.el (eglot--guess-contact): Tweak prompt for
    major mode.  (Bug#60379)
    
    Copyright-paperwork-exempt: yes
---
 lisp/progmodes/eglot.el | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lisp/progmodes/eglot.el b/lisp/progmodes/eglot.el
index 6d192d9b33..0082a17130 100644
--- a/lisp/progmodes/eglot.el
+++ b/lisp/progmodes/eglot.el
@@ -991,6 +991,7 @@ Return (MANAGED-MODE PROJECT CLASS CONTACT LANG-ID).  If 
INTERACTIVE is
 non-nil, maybe prompt user, else error as soon as something can't
 be guessed."
   (let* ((guessed-mode (if buffer-file-name major-mode))
+         (guessed-mode-name (and guessed-mode (symbol-name guessed-mode)))
          (main-mode
           (cond
            ((and interactive
@@ -1000,7 +1001,7 @@ be guessed."
              (completing-read
               "[eglot] Start a server to manage buffers of what major mode? "
               (mapcar #'symbol-name (eglot--all-major-modes)) nil t
-              (symbol-name guessed-mode) nil (symbol-name guessed-mode) nil)))
+              guessed-mode-name nil guessed-mode-name nil)))
            ((not guessed-mode)
             (eglot--error "Can't guess mode to manage for `%s'" 
(current-buffer)))
            (t guessed-mode)))