(interactive "P")
(quit-window kill-buffer))
+(defun magit-diff-master-mergebase (&optional args files)
+ (interactive (magit-diff-arguments))
+ (magit-diff-working-tree
+ (magit-git-string "merge-base" "master" "HEAD") args files))
+
+(magit-define-popup-action 'magit-diff-popup
+ ?m "Diff merge-base master" 'magit-diff-master-mergebase)
+
; ignore whitespace
; (setq magit-diff-options '("-w"))