magit-branch-backup-current: Allow arbitrary name

1 files changed, 23 insertions, 17 deletions

diff --git a/lisp/km-magit.el b/lisp/km-magit.el
index fa7d3af..7162e8e 100644
--- a/lisp/km-magit.el
+++ b/lisp/km-magit.el
@@ -209,24 +209,30 @@ START-POINT set to the current branch.
                                           (concat it "-tmp")))))
   (magit-run-git "checkout" "-b" branch))
 
-(defun km/magit-branch-backup-current ()
+(defun km/magit-branch-backup-current (&optional choose-name)
   "Create a backup branch for the current branch.
-\n(git branch b/<current-branch>__vN)"
-  (interactive)
-  (let* ((current (or (magit-get-current-branch)
-                      (user-error "No current branch")))
-         (version-re (format "\\`b/%s__v\\([[:digit:]]+\\)\\'" current))
-         (versions (delq nil
-                         (mapcar
-                          (lambda (s)
-                            (and (string-match version-re s)
-                                 (string-to-number
-                                  (match-string-no-properties 1 s))))
-                          (magit-list-local-branch-names))))
-         (vbranch (format "b/%s__v%d"
-                          current
-                          (if (null versions) 1 (1+ (apply #'max versions))))))
-    (magit-run-git "branch" vbranch)))
+With the prefix argument CHOOSE-NAME, prompt for the name of the
+backup branch.  Otherwise, name it as 'b/<current-branch>__v<n>',
+where <n> is incremented to form a refname that doesn't already
+exist."
+  (interactive "P")
+  (let ((current (or (magit-get-current-branch)
+                     (user-error "No current branch"))))
+    (magit-run-git
+     "branch"
+     (if choose-name
+         (magit-read-string-ns "Backup name" current)
+       (let* ((version-re (format "\\`b/%s__v\\([[:digit:]]+\\)\\'" current))
+              (versions (delq nil
+                              (mapcar
+                               (lambda (s)
+                                 (and (string-match version-re s)
+                                      (string-to-number
+                                       (match-string-no-properties 1 s))))
+                               (magit-list-local-branch-names)))))
+         (format "b/%s__v%d"
+                 current
+                 (if (null versions) 1 (1+ (apply #'max versions)))))))))
 
 (defun km/magit-mode-bury-all-windows (&optional kill-buffer)
   "Run `magit-mode-quit-window' until no longer in Magit buffer."