Tabs hiding does not work

[georgtree]

Hello!
Tabs hiding function doesnt work, despite the fact it provides right results:

  (defun centaur-tabs-hide-tab (buffer)
    "Hide BUFFER from the tab bar if it matches various criteria."
    (let ((name (buffer-name buffer))
          result)
      (with-current-buffer buffer
        (setq result
              (or
               ;; Hide *Ilist* buffers
               (string-prefix-p "*Ilist" name)
               ;; Sidebar
               (eq major-mode 'dired-sidebar-mode)
               ;; Blacklisted buffers
               (string-prefix-p "*epc" name)
               (string-prefix-p "*helm" name)
               (string-prefix-p "*Helm" name)
               (string-prefix-p "*Compile-Log*" name)
               (string-prefix-p "*lsp" name)
               (string-prefix-p "*company" name)
               (string-prefix-p "*Flycheck" name)
               (string-prefix-p "*tramp" name)
               (string-prefix-p " *Mini" name)
               (string-prefix-p "*help" name)
               (string-prefix-p "*straight" name)
               (string-prefix-p " *temp" name)
               (string-prefix-p "*Help" name)
               (string-prefix-p "*mybuf" name)
               ;; Magit internal buffers (no extension)
               (and (string-prefix-p "magit" name)
                    (not (file-name-extension name))))))
      ;; Log buffer and result
      (message "[centaur-tabs] %s → hide: %s" name result)
      result))
  (setq centaur-tabs-hide-tab-function #'centaur-tabs-hide-tab)

In messages:

[centaur-tabs] :~/emacs_config/ → hide: t
[centaur-tabs] *Warnings* → hide: nil
[centaur-tabs] *scratch* → hide: nil
[centaur-tabs] :~/ → hide: t
[centaur-tabs] *Messages* → hide: nil

It is still shown in the tab line, and I can cycle to these buffers.
Thank you in advance.

[georgtree]

But maybe I don't understand what does it means hide tabs? I think it exclude from displaying certain buffer from tab line, not hiding the whole tab line for the group

[jcs090218]

It means don't display these buffers in tab line. 🤔

What are you trying to achieve? If you are trying to do something more advanced, you can take a look at my configuration. It might help: https://github.com/jcs-emacs/jcs-emacs/blob/master/modules/ui/tabs/config.el.

[georgtree]

Hello, I want to hide buffers that comes from dired-sidebar and imenu-list, but they are not hiding at all despite adding it to centaur-tabs-hide-tab function. The only way I can get rid of it is to put them in separate groups, but it does not solve the issue with cycling through the tabs. Looks like hiding doesn't work at all.
Full config is:

(use-package centaur-tabs
  :ensure t
  :demand
  :config
  (centaur-tabs-mode t)
  (centaur-tabs-headline-match)
  (setq centaur-tabs-show-new-tab-button t
        centaur-tabs-set-modified-marker t
        centaur-tabs-show-navigation-buttons t
        centaur-tabs-style "bar"
        centaur-tabs-height 20
        centaur-tabs-close-button "X"
        centaur-tabs-cycle-scope 'tab)
  (centaur-tabs-change-fonts (face-attribute 'default :font) 80)
  (defun centaur-tabs-hide-tab (buffer)
    "Hide BUFFER from the tab bar if it matches various criteria."
    (let ((name (buffer-name buffer))
          result)
      (with-current-buffer buffer
        (setq result
              (or
               ;; Hide *Ilist* buffers
               (string-prefix-p "*Ilist" name)
               ;; Sidebar
               (eq major-mode 'dired-sidebar-mode)
               ;; Blacklisted buffers
               (string-prefix-p "*epc" name)
               (string-prefix-p "*helm" name)
               (string-prefix-p "*Helm" name)
               (string-prefix-p "*Compile-Log*" name)
               (string-prefix-p "*lsp" name)
               (string-prefix-p "*company" name)
               (string-prefix-p "*Flycheck" name)
               (string-prefix-p "*tramp" name)
               (string-prefix-p " *Mini" name)
               (string-prefix-p "*help" name)
               (string-prefix-p "*straight" name)
               (string-prefix-p " *temp" name)
               (string-prefix-p "*Help" name)
               (string-prefix-p "*mybuf" name)
               ;; Magit internal buffers (no extension)
               (and (string-prefix-p "magit" name)
                    (not (file-name-extension name))))))
      ;; Log buffer and result
      (message "[centaur-tabs] %s → hide: %s" name result)
      result))
  (setq centaur-tabs-hide-tab-function #'centaur-tabs-hide-tab)
  (defun centaur-tabs-buffer-groups  ()
    "Group buffers for centaur-tabs, isolating sidebar and system buffers, using Projectile when possible."
    (list
     (cond
      ((string-prefix-p "*Ilist" (buffer-name)) "Ilist")
      ((eq major-mode 'dired-sidebar-mode) "Sidebar")
      ((string-prefix-p "*Man " (buffer-name)) "ManPages")
      ((or (string-prefix-p "*" (buffer-name))
           (memq major-mode '(magit-process-mode
                              magit-status-mode
                              magit-diff-mode
                              magit-log-mode
                              magit-file-mode
                              magit-blob-mode
                              magit-blame-mode))) "Emacs")
      ((derived-mode-p 'dired-mode) "Dired")
      ((and (fboundp 'projectile-project-name)
            (projectile-project-name))
       (projectile-project-name))
      (t "Common"))))
  (defun my/set-centaur-tabs-faces-based-on-background ()
    "Set centaur-tabs faces based on whether the background is light or dark."
    (let ((mode (frame-parameter nil 'background-mode)))
      (if (eq mode 'dark)
          (progn
            (set-face-attribute 'centaur-tabs-selected nil :background "#444444" :foreground "#f8f8f2")
            (set-face-attribute 'centaur-tabs-selected-modified nil :background "#444444" :foreground "#f8f8f2")
            (set-face-attribute 'centaur-tabs-unselected nil :background "#383838" :foreground "#6272a4")
            (set-face-attribute 'centaur-tabs-unselected-modified nil :background "#383838" :foreground "#6272a4"))
        (progn
          (set-face-attribute 'centaur-tabs-selected nil :background "#cacacb" :foreground "black")
          (set-face-attribute 'centaur-tabs-selected-modified nil :background "#cacacb" :foreground "black")
          (set-face-attribute 'centaur-tabs-unselected nil :background "#fafafa" :foreground "black")
          (set-face-attribute 'centaur-tabs-unselected-modified nil :background "#fafafa" :foreground "black")))))

  ;; Reapply faces after any theme is loaded
  (advice-add 'load-theme :after (lambda (&rest _) (my/set-centaur-tabs-faces-based-on-background)))
  ;; Apply immediately at startup in case a theme is already active
  (my/set-centaur-tabs-faces-based-on-background)
  :bind
  ("C-x <mouse-9>" . centaur-tabs-backward)
  ("C-x <mouse-8>" . centaur-tabs-forward)
  ("C-S-<prior>" . centaur-tabs-move-current-tab-to-left)
  ("C-S-<next>" . centaur-tabs-move-current-tab-to-right))

[georgtree]

If i comment out the grouping of these buffers:

(defun centaur-tabs-buffer-groups  ()
    "Group buffers for centaur-tabs, isolating sidebar and system buffers, using Projectile when possible."
    (list
     (cond
      ;;((string-prefix-p "*Ilist" (buffer-name)) "Ilist")
      ;;((eq major-mode 'dired-sidebar-mode) "Sidebar")
      ((string-prefix-p "*Man " (buffer-name)) "ManPages")
      ((or (string-prefix-p "*" (buffer-name))
           (memq major-mode '(magit-process-mode
                              magit-status-mode
                              magit-diff-mode
                              magit-log-mode
                              magit-file-mode
                              magit-blob-mode
                              magit-blame-mode))) "Emacs")
      ;;((derived-mode-p 'dired-mode) "Dired")
      ((and (fboundp 'projectile-project-name)
            (projectile-project-name))
       (projectile-project-name))
      (t "Common"))))

I got dired-sidebar buffer in the tabs:

But function centaur-tabs-hide-tab returns:

[centaur-tabs] :~/emacs_config/ → hide: t

Update - maybe the grouping with projectile brings the hidden tab back to tab line?

[georgtree]

Ok, it looks like function centaur-tabs-hide-tab actually hides the tab line IN these buffers, but not prevent from showing these buffers in tab line as a part of the group.