Subject: bug#71883: [PATCH] Fix tab-bar-auto-width with customized tab-bar-tab-face-function

From: Joseph Turner <[email-masked]>
Date: Mon, 15 Jul 2024 22:12:46 -0700

Juri Linkov <[email-masked]> writes:

> Let's see what Joseph and Stephane think.

Please see the attached patches, where the first three commits are
intended to be applied to the emacs-30 branch, and the final commit
removes the obsolete `tab-bar-auto-width-faces' on master.

Does this change warrant a NEWS entry?

Thanks!

Joseph

>From 050a574bcab371ee87b1ed6c15e6431a3c2ed4d8 Mon Sep 17 00:00:00 2001
From: Juri Linkov <[email-masked]>
Date: Mon, 15 Jul 2024 21:23:39 -0700
Subject: [PATCH 1/4] Use current-group symbol for current tab group item

* lisp/tab-bar.el (tab-bar--format-tab-group):
---
 lisp/tab-bar.el | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index edec6543a82..66fb9490ce8 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1044,7 +1044,7 @@ tab-bar--format-tab-group
 when the tab is current.  Return the result as a keymap."
   (append
    `((,(intern (format "sep-%i" i)) menu-item ,(tab-bar-separator) ignore))
-   `((,(intern (format "group-%i" i))
+   `((,(intern (if current-p "current-group" (format "group-%i" i)))
       menu-item
       ,(if current-p
            (condition-case nil
-- 
2.41.0

>From ca66acf2a4ded69e07a796d3feb1906072c20e6c Mon Sep 17 00:00:00 2001
From: Joseph Turner <[email-masked]>
Date: Mon, 15 Jul 2024 21:55:35 -0700
Subject: [PATCH 2/4] Add abnormal hook to determine which tabs to auto-widen

* lisp/tab-bar.el (tab-bar-auto-width-predicate-default):  Default value
for tab-bar-auto-width-functions.
(tab-bar-auto-width-functions): New abnormal hook.
(tab-bar-auto-width): Run new abnormal hook until success instead of
comparing text properties on Emacs 31 or later.
---
 lisp/tab-bar.el | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index 66fb9490ce8..86259f36df5 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1222,6 +1222,18 @@ tab-bar-auto-width-faces
      tab-bar-tab-group-inactive)
   "Resize tabs only with these faces.")
 
+(defun tab-bar-auto-width-predicate-default (item)
+  "Accepts tab ITEM and returns non-nil for tabs and tab groups."
+  (string-match-p
+   ;; (rx bos (or "current-tab" "current-group" "tab-" "group-"))
+   "\\`\\(?:current-\\(?:group\\|tab\\)\\|\\(?:group\\|tab\\)-\\)"
+   (symbol-name (nth 0 item))))
+
+(defvar tab-bar-auto-width-functions '(tab-bar-auto-width-predicate-default)
+  "List of functions for `tab-bar-auto-width' to call with a tab ITEM.
+If any of these functions returns non-nil for a given tab ITEM, that
+tab's width will be auto-sized.")
+
 (defvar tab-bar--auto-width-hash nil
   "Memoization table for `tab-bar-auto-width'.")
 
@@ -1250,8 +1262,10 @@ tab-bar-auto-width
         (width 0))    ;; resize tab names to this width
     (dolist (item items)
       (when (and (eq (nth 1 item) 'menu-item) (stringp (nth 2 item)))
-        (if (memq (get-text-property 0 'face (nth 2 item))
-                  tab-bar-auto-width-faces)
+        (if (if (version<= "31" emacs-version)
+                (run-hook-with-args-until-success 'tab-bar-auto-width-functions item)
+              (memq (get-text-property 0 'face (nth 2 item))
+                    tab-bar-auto-width-faces))
             (push item tabs)
           (unless (eq (nth 0 item) 'align-right)
             (setq non-tabs (concat non-tabs (nth 2 item)))))))
-- 
2.41.0

>From 89c7c43219569df5d78a3677aeff7f5e20d83330 Mon Sep 17 00:00:00 2001
From: Joseph Turner <[email-masked]>
Date: Mon, 15 Jul 2024 22:05:40 -0700
Subject: [PATCH 3/4] Mark tab-bar-auto-width-faces obsolete

* lisp/tab-bar.el: (tab-bar-auto-width-faces) Obsolete on >=30.
---
 lisp/tab-bar.el | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index 86259f36df5..853f487743d 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1216,6 +1216,7 @@ tab-bar-auto-width-min
 It's not recommended to change this value since with larger values, the
 tab bar might wrap to the second line when it shouldn't.")
 
+(make-obsolete-variable 'tab-bar-auto-width-faces 'tab-bar-auto-width-functions "30")
 (defvar tab-bar-auto-width-faces
   '( tab-bar-tab tab-bar-tab-inactive
      tab-bar-tab-ungrouped
-- 
2.41.0

>From fa939a20ad4752bdf6d591b09ec69e14981aa714 Mon Sep 17 00:00:00 2001
From: Joseph Turner <[email-masked]>
Date: Mon, 15 Jul 2024 22:07:22 -0700
Subject: [PATCH 4/4] Remove obsolete tab-bar-auto-width-faces

* lisp/tab-bar.el (tab-bar-auto-width-faces):  Remove.
(tab-bar-auto-width): Only run tab-bar-auto-width-functions.
---
 lisp/tab-bar.el | 12 +-----------
 1 file changed, 1 insertion(+), 11 deletions(-)

diff --git a/lisp/tab-bar.el b/lisp/tab-bar.el
index 853f487743d..57ea78414bc 100644
--- a/lisp/tab-bar.el
+++ b/lisp/tab-bar.el
@@ -1216,13 +1216,6 @@ tab-bar-auto-width-min
 It's not recommended to change this value since with larger values, the
 tab bar might wrap to the second line when it shouldn't.")
 
-(make-obsolete-variable 'tab-bar-auto-width-faces 'tab-bar-auto-width-functions "30")
-(defvar tab-bar-auto-width-faces
-  '( tab-bar-tab tab-bar-tab-inactive
-     tab-bar-tab-ungrouped
-     tab-bar-tab-group-inactive)
-  "Resize tabs only with these faces.")
-
 (defun tab-bar-auto-width-predicate-default (item)
   "Accepts tab ITEM and returns non-nil for tabs and tab groups."
   (string-match-p
@@ -1263,10 +1256,7 @@ tab-bar-auto-width
         (width 0))    ;; resize tab names to this width
     (dolist (item items)
       (when (and (eq (nth 1 item) 'menu-item) (stringp (nth 2 item)))
-        (if (if (version<= "31" emacs-version)
-                (run-hook-with-args-until-success 'tab-bar-auto-width-functions item)
-              (memq (get-text-property 0 'face (nth 2 item))
-                    tab-bar-auto-width-faces))
+        (if (run-hook-with-args-until-success 'tab-bar-auto-width-functions item)
             (push item tabs)
           (unless (eq (nth 0 item) 'align-right)
             (setq non-tabs (concat non-tabs (nth 2 item)))))))
-- 
2.41.0