Is there something like a git format-patch --squash?

On Thu, Feb 18, 2010 at 1:38 PM, Avery Pennarun <apenwarr@gmail.com> wrote:

In the above, in the 'else' clause, what I really wanted was something like:

   git format-patch --stdout --squash $parent..$commit

with one big "| git am" at the end of the loop.

However, format-patch seems to have no way of just producing a single patch with all the changes from a particular branch. Is there some other easy command that would do what I want? It seems like something that someone would have wanted before now.

Thanks,

Avery

On Thu, Feb 18, 2010 at 2:45 PM, Avery Pennarun <apenwarr@gmail.com> wrote:

Um, where the unstated actual problem is that format-patch has no "--squash" option. :)

Avery

On Thu, Feb 18, 2010 at 02:45:54PM -0500, Avery Pennarun wrote:

I don't think there is a way to do it automagically. Obviously you can use diff (as you did) to produce the diff, but how should the many commit messages be combined?

Worst case, you could probably do it yourself by echoing the mail headers yourself, throwing all of the commit messages in the body, and then doing the diff:

  me=`git var GIT_AUTHOR_IDENT | sed -e 's/>.*/>/'`
  (echo "From: $me"
   echo "Subject: Mega-squash of $commit"
   echo
   git log --format="%s%n%n%b" $parent..$commit
   echo ---
   git diff $parent $commit
  ) | git am

But that's totally untested (also, do you really need $parent? In --first-parent --reverse, isn't it always going to be $commit^1?).

But I think you can do it without diff application by just re-using the tree-state of each merge:

  git rev-list --first-parent --reverse $from..$to |
  last=$from
  while read commit; do
    last=`git cat-file commit $commit |
          sed '1,/^$/d' |
          git commit-tree $commit^{tree} -p $from`
  done
  git update-ref refs/heads/new $last

But that isn't tested either. :) You might need to replace "$commit^{tree}" with an equivalent rev-parse.

-Peff

On Thu, Feb 18, 2010 at 3:34 PM, Jeff King <peff@peff.net> wrote:

Something like what merge --squash does would be fine, I think.

As it happens, the script I wrote ends up using the commit message from merge commits (since those are the ones that end up including all the patches from their side branch), which is precisely equivalent to how it would look in a "linearizing" SCM like svn or cvs.

I happen to have merge.summary=true in my ~/.gitconfig so my merge commits have extra information in them, though.

True. But format-patch already has the code for that, so it's kind of error-prone to duplicate it.

Good point. That script was quickly hacked together after a few iterations that previously did more important things with $parent.

I don't think that works, since commit-tree takes the commit message on stdin but the other stuff via environment variables. Which is too bad, really, at least for this case.

Have fun,

Avery