:title: ediff
:date: 2026-06-10
:tags: ediff
:identifier: 20260610T182004
:signature: 5=15

``ediff``
=========

Below are my customisations for ``ediff``, explanations are captured in follow on sections

.. code-block:: elisp
   :project: emacs
   :filename: init.el

   (use-package alc-ediff
     :load-path "lisp"
     :custom
     ((ediff-window-setup-function 'alc-ediff-window-setup-function))
     :config
     ;; I tried setting these via `:hook` but they seemed to be clobbered by ediff's setup code...
     (add-hook 'ediff-suspend-hook #'alc-ediff-suspend-hook)
     (add-hook 'ediff-quit-hook #'alc-ediff-quit-hook))


Window Management
-----------------

``ediff`` runs an arbitrary function ``ediff-window-setup-function`` to configure the window layout at the start of an ediff session.
I'm quite happy with ``ediff-setup-windows-plain``, the only tweak I want to make is to have the window layout open in a new tab.

.. code-block:: elisp
   :project: emacs
   :filename: lisp/alc-ediff.el
   :template: elisp-module

   (require 'ediff)

   (defun alc-ediff-window-setup-function (&rest args)
     "Configure the window layout for an ediff session."
     (tab-new)
     (apply #'ediff-setup-windows-plain args))

Of course, the newly created tab should be closed on session quit/suspend.

.. code-block:: elisp
   :project: emacs
   :filename: lisp/alc-ediff.el

   (defun alc-ediff-suspend-hook ()
     "Close the tab created by `alc-ediff-window-setup-function'."
     (tab-close))

   (defun alc-ediff-quit-hook ()
     "Close the tab created by `alc-ediff-window-setup-function'."
     (tab-close))