diffstat wierdness with 'git format-patch' output

I was trying to use the built-in git tools to send patches off, instead of my horribly hacked up scripts that use the git low-level stuff, when I noticed that git format-patch's output confuses diffstat a bit, and causes it to add another line to it's count.

This isn't good when I do a 'diffstat -p1 *.txt' of the output and add it to an email to send off for someone to pull from, as the result will be off from what is really there.

Here's what I get:

 $ git format-patch -n origin..HEAD
 0001-USB-fix-up-the-usb-early-handoff-logic-for-EHCI.txt
 0002-USB-add-new-device-ids-to-ldusb.txt
 0003-USB-change-ldusb-s-experimental-state.txt
 0004-USB-PL2303-Leadtek-9531-GPS-Mouse.txt
 0005-USB-sl811_cs-needs-platform_device-conversion-too.txt
 0006-usb-storage-new-unusual_devs-entry.txt
 0007-usb-storage-unusual_devs-entry.txt
 0008-USB-unusual_devs.h-entry-TrekStor-i.Beat.txt
 0009-USB-unusual_devs.h-entry-iAUDIO-M5.txt
 0010-USB-unusual-devs-bugfix.txt

 $ git log | head -n 1
 commit 16f05be7be0bf121491d83bd97337fe179b3b323

 $ git show 16f05be7be0bf121491d83bd97337fe179b3b323 | diffstat -p1
  drivers/usb/storage/unusual_devs.h |   25 ++++++++++++++++++-------
  1 file changed, 18 insertions(+), 7 deletions(-)

 $ diffstat -p1 0010-USB-unusual-devs-bugfix.txt
  drivers/usb/storage/unusual_devs.h |   26 ++++++++++++++++++--------
  1 file changed, 18 insertions(+), 8 deletions(-)

Any thoughts?

thanks,

greg k-h

On Mon, Feb 13, 2006 at 09:54:25PM -0800, Greg KH wrote:

Hm, in looking at it closer, it's probably the last two lines of the
file, the signature that git format-patch adds to the message:
	-- 
	1.2.0

Any way to suppress these?

thanks,

greg k-h

Greg KH <greg@kroah.com> writes:

If that is the case, it's unfortunate that diffstat is broken and is not properly counting lines to tell which lines are part of the patch and which lines are not.

Have you tried "git apply --stat" instead?

Sorry, there is no option to disable that, but the stuff is GPLv2 so you can do whatever ;-).

The string "-- \n" is an established convention to mark the beginning of the signature (or whatever inmaterial stuff that follow the message contents), so changing the marker is pointless -- if we want the option it should be to delete those two lines altogether.

I personally find it useful to see the trend of version of tools people use on the public mailing list, and that was the primary reason it is there.

Have you tried "git apply --stat --summary" instead?

On Mon, Feb 13, 2006 at 10:09:30PM -0800, Junio C Hamano wrote:

How would that work after I've allready applied the patches to a branch?

Bah, make me go create a patch :)

Oh I understand what it is and it does follow the proper convention. Maybe we just need an extra line of padding in there before the signature or something... I'll go play with it.

Why not just add a "X-Git-Version: 1.2.0" flag to the message instead?

thanks,

greg k-h

Greg KH <greg@kroah.com> writes:

Sorry I was unclear. By "instead", I meant "instead of running diffstat -p1".

On Mon, Feb 13, 2006 at 10:37:59PM -0800, Junio C Hamano wrote:

That doesn't give me a summary of all of the changes I made to the tree:

$ git apply --stat *.txt
 drivers/hwmon/vt8231.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
 drivers/hwmon/w83781d.c |   43 +++++++++++++++++++++++++------------------
 1 files changed, 25 insertions(+), 18 deletions(-)
 Documentation/hwmon/w83627hf |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
 drivers/hwmon/it87.c         |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
 drivers/i2c/busses/i2c-isa.c |   12 ------------
 1 files changed, 0 insertions(+), 12 deletions(-)

Instead of:

 Documentation/hwmon/w83627hf |    4 ++++
 drivers/hwmon/it87.c         |    3 ++-
 drivers/hwmon/vt8231.c       |    8 ++++----
 drivers/hwmon/w83781d.c      |   43 +++++++++++++++++++++++++------------------
 drivers/i2c/busses/i2c-isa.c |   12 ------------
 5 files changed, 35 insertions(+), 35 deletions(-)

Which is what I need to put into a "please pull from this tree" email message.

thanks,

greg k-h

On Mon, Feb 13, 2006 at 10:34:20PM -0800, Greg KH wrote:

And here's a patch that does just that.

-----------------

Subject: change git-format-patch to put the git version in the mail header

This is more like other tools that create mail messages, and fixes an issue of the diffstat program thinking that an extra line was removed from the patch.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

On Mon, Feb 13, 2006 at 10:42:56PM -0800, Greg KH wrote:

Hm, git-send-email doesn't see this, so it doesn't get sent out if you use that tool.

I can fix that to just put the version number in the message too, like it adds the "X-Mailer" field, if people think this is really worth it...

thanks,

greg k-h

Greg KH <greg@kroah.com> writes:

And people are very likely to remove it by hand.

Another possibility would be to use "git apply --numstat" and add numbers up in your script, but that would not give you a nice graph output either X-<.

I'd say if you really care we should just remove those two lines, and remember I am _very_ receptive from such suggestion from prominent kernel people.

On Mon, Feb 13, 2006 at 11:10:18PM -0800, Junio C Hamano wrote:

Hm, in thinking about this some more, I realized that it only requires me to change my script to generate the emails for Linus to pull from a tiny bit, making this whole thing not a bit deal at all.

Thanks a lot for being so receptive, if I have further problems with it, I'll let you know.

greg k-h

On Mon, Feb 13, 2006 at 09:54:25PM -0800, Greg KH wrote:

If you don't have to generate the diffstat from the individual patches then

    git-diff-tree -p origin HEAD | git-apply --stat

should give you what you want.

BTW when I tried the above command on two random tags in the git tree I got:

    $ git-diff-tree -p v1.2.0 v1.0.8 | diffstat -p1 | tail -1
    165 files changed, 3913 insertions(+), 8092 deletions(-)

and

    $ git-diff-tree -p v1.2.0 v1.0.8 | git apply --stat | tail -1
    160 files changed, 3925 insertions(+), 8092 deletions(-)

The difference seems to be caused by diffstat which seems to think that all lines starting with '---' are diff headers. Hence, there are some bogus files in the diffstat output such as:

    [master]                                          |  177 ++
    [master^2~4]                                      |    9 
    [master^]                                         |   24 
    [mybranch]                                        |   56 
    [mybranch^]                                       |  616 +++++++

- Fredrik