Re: combine git repo historically

On Sunday 11 October 2009, bill lam wrote:

On Sun, 11 Oct 2009, Christian Couder wrote:

quoted

$ git checkout -b repo1-branch1 remote/repo1/branch1
$ git checkout N -- .
...
If everything is ok then you can use:

$ git replace N HEAD

Thanks for detail instruction, I tested it ok except that when trying
to checkout it reported an error

  $ git checkout -b repo1-branch1 remote/oldjproject/master
  fatal: git checkout: updating paths is incompatible with switching
branches. Did you intend to checkout 'remote/oldjproject/master' which
can not be resolved as commit?

but it ran ok by omitting that 'remote/'
$ git checkout -b repo1-branch1 oldjproject/master

Does it need to purge the file system tree before
  git checkout N -- .

so that there will be no artifact leaved by M?

Yeah, perhaps, I forgot that there could be some files added and other files 
removed between M and N.

If you remove everything (except the .git directory of course), then doing:

$ git checkout N -- .
$ git add .
$ export GIT_AUTHOR_NAME=<author name of commit N>
$ export GIT_AUTHOR_EMAIL=<author email of commit N>
$ export GIT_AUTHOR_DATE=<date of commit N>
$ git commit

should do the trick if I am not missing something which may very well be the 
case.

So perhaps it is easier to use Jakub's suggestion instead.

I found that it is necessary to do a
   git reset --hard (original HEAD)

to complete the story. Is it correct?

Yes, you should go back to your orginal branch at the end.

Regards,
Christian.