[PATCH] git.el: Diff only file at point by default

["David Kågedal" <davidk@lysator.liu.se>]

Use prefix (C-u) to diff all marked files instead.

Signed-off-by: David Kågedal <davidk@lysator.liu.se>
---
 contrib/emacs/git.el |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

For anyone who has used pcvs (or dsvn) this makes much more sense. The
typical usage scenario is that you want to mark the files that are
relevant, and you do it incrementally by checking if file A is
relevant and has no strange changes by pressing = and then marking it,
proceeding to check file B by pressing = on it and potentially marking
it as well and so on.

The current way that = works means that you have to check each file
first and remember which one you want to mark. Or diff everything and
then read through the whole diff and find match the output against the
files to mark. It is possible to do it like that as well, but it is
much more convenient to do it as described above, and there is a
strong precedent in emacs frontends to make the diff command only diff
the current file by default.

The old behaviour can be restored by using C-u =.

diff --git a/contrib/emacs/git.el b/contrib/emacs/git.el
index c30d20a..a3477a4 100644
--- a/contrib/emacs/git.el
+++ b/contrib/emacs/git.el
@@ -772,6 +772,11 @@ Return the list of files that haven't been handled."
               (setq file (pop files))
             (setq node (ewoc-next status node))))))))
 
+(defun git-current-file ()
+  "Return the file at point."
+  (unless git-status (error "Not in git-status buffer."))
+  (ewoc-data (ewoc-locate git-status)))
+
 (defun git-marked-files ()
   "Return a list of all marked files, or if none a list containing just the file at cursor position."
   (unless git-status (error "Not in git-status buffer."))
@@ -1138,10 +1143,10 @@ Return the list of files that haven't been handled."
   (when (eq (window-buffer) (current-buffer))
     (shrink-window-if-larger-than-buffer)))
 
-(defun git-diff-file ()
-  "Diff the marked file(s) against HEAD."
-  (interactive)
-  (let ((files (git-marked-files)))
+(defun git-diff-file (arg)
+  "Diff the marked file(s) against HEAD, or the marked files if a prefix arg is given."
+  (interactive "P")
+  (let ((files (if arg (git-marked-files) (list (git-current-file)))))
     (git-setup-diff-buffer
      (apply #'git-run-command-buffer "*git-diff*" "diff-index" "-p" "-M" "HEAD" "--" (git-get-filenames files)))))
 
-- 
1.6.0.rc2.7.gbf8a


-- 
David Kågedal