master 29c0b64 2/2: * lisp/tab-line.el (tab-line-tab-name-format-function): New defcustom.

[Juri Linkov]

branch: master
commit 29c0b640ba7bd076345d654fc5c393062eab83af
Author: Juri Linkov <juri@linkov.net>
Commit: Juri Linkov <juri@linkov.net>

    * lisp/tab-line.el (tab-line-tab-name-format-function): New defcustom.
    
    (tab-line-tab-name-format-default): New function as the default value.
    (tab-line-format-template): Funcall tab-line-tab-name-format-function.
    This is like recently added tab-bar-tab-name-format-function.
---
 etc/NEWS         |  3 +++
 lisp/tab-line.el | 74 +++++++++++++++++++++++++++++++++-----------------------
 2 files changed, 47 insertions(+), 30 deletions(-)

diff --git a/etc/NEWS b/etc/NEWS
index 122ac50..5df8ee1 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -502,6 +502,9 @@ It also supports a negative argument.
 *** New user option 'tab-bar-tab-name-format-function'.
 
 ---
+*** New user option 'tab-line-tab-name-format-function'.
+
+---
 *** The tabs in the tab line can now be scrolled using horizontal scroll.
 If your mouse or trackpad supports it, you can now scroll tabs when
 the mouse pointer is in the tab line by scrolling left or right.
diff --git a/lisp/tab-line.el b/lisp/tab-line.el
index 1bdddc2..903862a 100644
--- a/lisp/tab-line.el
+++ b/lisp/tab-line.el
@@ -430,42 +430,56 @@ variable `tab-line-tabs-function'."
             next-buffers)))
 
 
+(defcustom tab-line-tab-name-format-function #'tab-line-tab-name-format-default
+  "Function to format a tab name.
+Function gets two arguments: the tab and a list of all tabs, and
+should return the formatted tab name to display in the tab line."
+  :type 'function
+  :initialize 'custom-initialize-default
+  :set (lambda (sym val)
+         (set-default sym val)
+         (force-mode-line-update))
+  :group 'tab-line
+  :version "28.1")
+
+(defun tab-line-tab-name-format-default (tab tabs)
+  (let* ((buffer-p (bufferp tab))
+         (selected-p (if buffer-p
+                         (eq tab (window-buffer))
+                       (cdr (assq 'selected tab))))
+         (name (if buffer-p
+                   (funcall tab-line-tab-name-function tab tabs)
+                 (cdr (assq 'name tab))))
+         (face (if selected-p
+                   (if (eq (selected-window) (old-selected-window))
+                       'tab-line-tab-current
+                     'tab-line-tab)
+                 'tab-line-tab-inactive)))
+    (dolist (fn tab-line-tab-face-functions)
+      (setf face (funcall fn tab tabs face buffer-p selected-p)))
+    (apply 'propertize
+           (concat (propertize name 'keymap tab-line-tab-map)
+                   (or (and (or buffer-p (assq 'buffer tab) (assq 'close tab))
+                            tab-line-close-button-show
+                            (not (eq tab-line-close-button-show
+                                     (if selected-p 'non-selected 'selected)))
+                            tab-line-close-button)
+                       ""))
+           `(
+             tab ,tab
+             ,@(if selected-p '(selected t))
+             face ,face
+             mouse-face tab-line-highlight))))
+
 (defun tab-line-format-template (tabs)
   "Template for displaying tab line for selected window."
-  (let* ((selected-buffer (window-buffer))
-         (separator (or tab-line-separator (if window-system " " "|")))
+  (let* ((separator (or tab-line-separator (if window-system " " "|")))
          (hscroll (window-parameter nil 'tab-line-hscroll))
          (strings
           (mapcar
            (lambda (tab)
-             (let* ((buffer-p (bufferp tab))
-                    (selected-p (if buffer-p
-                                    (eq tab selected-buffer)
-                                  (cdr (assq 'selected tab))))
-                    (name (if buffer-p
-                              (funcall tab-line-tab-name-function tab tabs)
-                            (cdr (assq 'name tab))))
-                    (face (if selected-p
-                              (if (eq (selected-window) (old-selected-window))
-                                  'tab-line-tab-current
-                                'tab-line-tab)
-                            'tab-line-tab-inactive)))
-               (dolist (fn tab-line-tab-face-functions)
-                 (setf face (funcall fn tab tabs face buffer-p selected-p)))
-               (concat
-                separator
-                (apply 'propertize
-                       (concat (propertize name 'keymap tab-line-tab-map)
-                               (or (and (or buffer-p (assq 'buffer tab) (assq 
'close tab))
-                                        tab-line-close-button-show
-                                        (not (eq tab-line-close-button-show
-                                                 (if selected-p 'non-selected 
'selected)))
-                                        tab-line-close-button) ""))
-                       `(
-                         tab ,tab
-                         ,@(if selected-p '(selected t))
-                         face ,face
-                         mouse-face tab-line-highlight)))))
+             (concat separator
+                     (funcall tab-line-tab-name-format-function tab tabs)))
            tabs))
          (hscroll-data (tab-line-auto-hscroll strings hscroll)))
     (setq hscroll (nth 1 hscroll-data))