git subtree add -P <prefix> <commit> git subtree add -P <prefix> <repository> <ref> git subtree pull -P <prefix> <repository> <ref> git subtree push -P <prefix> <repository> <ref> git subtree merge -P <prefix> <commit> git subtree split -P <prefix> [OPTIONS] [<commit>]
Create the <prefix> subtree by importing its contents from the given <commit> or <repository> and remote <ref>. A new commit is created automatically, joining the imported project’s history with your own. With --squash, imports only a single commit from the subproject, rather than its entire history.merge
Merge recent changes up to <commit> into the <prefix> subtree. As with normal git merge, this doesn’t remove your own local changes; it just merges those changes into the latest <commit>. With --squash, creates only one commit that contains all the changes, rather than merging in the entire history. If you use --squash, the merge direction doesn’t always have to be forward; you can use this command to go back in time from v2.5 to v2.4, for example. If your merge introduces a conflict, you can resolve it in the usual ways.pull
Exactly like merge, but parallels git pull in that it fetches the given ref from the specified remote repository.push
Does a split (see below) using the <prefix> supplied and then does a git push to push the result to the repository and ref. This can be used to push your subtree to different branches of the remote repository.split
Extract a new, synthetic project history from the history of the <prefix> subtree. The new history includes only the commits (including merges) that affected <prefix>, and each of those commits now has the contents of <prefix> at the root of the project instead of in a subdirectory. Thus, the newly created history is suitable for export as a separate git repository. After splitting successfully, a single commit id is printed to stdout. This corresponds to the HEAD of the newly created tree, which you can manipulate however you want. Repeated splits of exactly the same history are guaranteed to be identical (i.e. to produce the same commit ids). Because of this, if you add new commits and then re-split, the new commits will be attached as commits on top of the history you generated last time, so git merge and friends will work as expected. Note that if you use --squash when you merge, you should usually not just --rejoin when you split.
Suppress unnecessary output messages on stderr.-d, --debug
Produce even more unnecessary output messages on stderr.-P <prefix>, --prefix=<prefix>
Specify the path in the repository to the subtree you want to manipulate. This option is mandatory for all commands.-m <message>, --message=<message>
This option is only valid for add, merge and pull (unsure). Specify <message> as the commit message for the merge commit.
This option is only valid for add, merge, and pull commands. Instead of merging the entire history from the subtree project, produce only a single commit that contains all the differences you want to merge, and then merge that new commit into your project. Using this option helps to reduce log clutter. People rarely want to see every change that happened between v1.0 and v1.1 of the library they’re using, since none of the interim versions were ever included in their application. Using --squash also helps avoid problems when the same subproject is included multiple times in the same project, or is removed and then re-added. In such a case, it doesn’t make sense to combine the histories anyway, since it’s unclear which part of the history belongs to which subtree. Furthermore, with --squash, you can switch back and forth between different versions of a subtree, rather than strictly forward. git subtree merge --squash always adjusts the subtree to match the exactly specified commit, even if getting to that commit would require undoing some changes that were added earlier. Whether or not you use --squash, changes made in your local repository remain intact and can be later split and send upstream to the subproject.
This option is only valid for the split command. When generating synthetic history, add <annotation> as a prefix to each commit message. Since we’re creating new commits with the same commit message, but possibly different content, from the original commits, this can help to differentiate them and avoid confusion. Whenever you split, you need to use the same <annotation>, or else you don’t have a guarantee that the new re-created history will be identical to the old one. That will prevent merging from working correctly. git subtree tries to make it work anyway, particularly if you use --rejoin, but it may not always be effective.-b <branch>, --branch=<branch>
This option is only valid for the split command. After generating the synthetic history, create a new branch called <branch> that contains the new history. This is suitable for immediate pushing upstream. <branch> must not already exist.--ignore-joins
This option is only valid for the split command. If you use --rejoin, git subtree attempts to optimize its history reconstruction to generate only the new commits since the last --rejoin. --ignore-join disables this behaviour, forcing it to regenerate the entire history. In a large project, this can take a long time.--onto=<onto>
This option is only valid for the split command. If your subtree was originally imported using something other than git subtree, its history may not match what git subtree is expecting. In that case, you can specify the commit id <onto> that corresponds to the first revision of the subproject’s history that was imported into your project, and git subtree will attempt to build its history from there. If you used git subtree add, you should never need this option.--rejoin
This option is only valid for the split command. After splitting, merge the newly created synthetic history back into your main project. That way, future splits can search only the part of history that has been added since the most recent --rejoin. If your split commits end up merged into the upstream subproject, and then you want to get the latest upstream version, this will allow git’s merge algorithm to more intelligently avoid conflicts (since it knows these synthetic commits are already part of the upstream repository). Unfortunately, using this option results in git log showing an extra copy of every new commit that was created (the original, and the synthetic one). If you do all your merges with --squash, don’t use --rejoin when you split, because you don’t want the subproject’s history to be part of your project anyway.
$ git subtree add --prefix=git-subtree --squash \ git://github.com/apenwarr/git-subtree.git master
$ git clone git://git.kernel.org/pub/scm/git/git.git test-git $ cd test-git
$ git subtree split --prefix=gitweb --annotate='(split) ' \ 0a8f4f0^.. --onto=1130ef3 --rejoin \ --branch gitweb-latest $ gitk gitweb-latest $ git push email@example.com:whatever/gitweb.git gitweb-latest:master
$ git subtree split --prefix=gitweb --annotate='(split) ' --rejoin \ --branch gitweb-latest2
$ git subtree pull --prefix=gitweb \ firstname.lastname@example.org:whatever/gitweb.git master
$ git subtree merge --prefix=gitweb --squash gitweb-latest~10
$ date >gitweb/myfile $ git add gitweb/myfile $ git commit -m 'created myfile'
$ git subtree merge --prefix=gitweb --squash gitweb-latest
$ ls -l gitweb/myfile
git log gitweb-latest..$(git subtree split --prefix=gitweb)
$ <go to the new location> $ git init --bare
$ git subtree split --prefix=lib --annotate="(split)" -b split
$ git push <new-repo> split:master