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+;;; oni-ediff.el --- Ediff configuration             -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2019  Tom Willemse
+
+;; Author: Tom Willemse <tom@ryuslash.org>
+;; Keywords: local
+;; Version: 20190226012954
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Ediff configuration.
+
+;;; Code:
+
+(require 'ediff)
+
+(defun oni-ediff--turn-on-fullscreen ()
+  "Turn on fullscreen for the current frame."
+  (unless (memq (frame-parameter nil 'fullscreen)
+                '(fullscreen fullboth))
+    (set-frame-parameter nil 'fullscreen 'fullboth)))
+
+(defun oni-ediff--turn-off-fullscreen ()
+  "Turn off fullscreen for the current frame."
+  (when (memq (frame-parameter nil 'fullscreen)
+              '(fullscreen fullboth))
+    (set-frame-parameter nil 'fullscreen nil)))
+
+(setq ediff-window-setup-function 'ediff-setup-windows-plain)
+(setq ediff-split-window-function 'split-window-horizontally)
+
+(setq ediff-diff-options "-w")
+
+(add-hook 'ediff-mode-hook #'oni-ediff--turn-on-fullscreen)
+(add-hook 'ediff-cleanup-hook #'oni-ediff--turn-off-fullscreen)
+
+;;;###autoload(with-eval-after-load 'ediff (require 'oni-ediff))
+
+(provide 'oni-ediff)
+;;; oni-ediff.el ends here