Re: merge removed content back into current content

From: Elijah Newren <newren@gmail.com>
Date: Sep 25, 2010, 23:43 UTC
Message-ID: <AANLkTimxHbCktv=kaq0UfV+u1kH1Pb2LYA2Xi=qkgduW@mail.gmail.com>
In-Reply-To: <i7jp1a$kc0$1@dough.gmane.org>

On Fri, Sep 24, 2010 at 9:06 PM, Neal Kreitzinger <neal@rsss.com> wrote:

Show 17 quoted lines

> How do I tell git to merge a single program from an old commit into the
> current version of that program in the HEAD commit?  In this scenario, I
> want to get back some removed code but still keep the new code.
>
> e.g.
>
> Commit-1 = initial commit containing Program-A, and other programs
>
> Commit-2 = add Changeset-1 to Program-A , and make changes to other programs
>
> Commit-3 = remove Changeset-1 from Program-A, then add Changeset-2 to
> Program-A, and make changes to other programs
>
> *desired* Commit-4 = only merge Program-A from Commit-2 into Program-A of
> Commit-3, and don't change any other programs
> (in other words, get my old changes from Commit-2 back, but don't loose the
> new changes from Commit-3)

Does something like:
  git diff commit1 commit2 -- ProgramA | git apply
do what you need?

If diff+apply doesn't work[1], you can try
  git cat-file -p commit1:ProgramA > base
  git cat-file -p commit2:ProgramA > other
  git cat-file -p commit3:ProgramA > current
  git merge-file current base other

[1] e.g. would cause conflicts -- btw, does anyone know how to force git apply to proceed and add conflict markers if necessary rather than just bailing out?