how to pull into multiple branches at once with git?

Question

In a repo I have multiple branches, among them "master" and "develop", which are set up to track remote branches "origin/master" and "origin/develop".

Is it possible to specify that I want both master and develop to be merged(fast-forwarded) at once?

When I do git pull now I get something like this:

remote: Counting objects: 92, done.
remote: Compressing objects: 100% (56/56), done.
remote: Total 70 (delta 29), reused 28 (delta 8)
Unpacking objects: 100% (70/70), done.
From scm.my-site.com:my-repo
   5386563..902fb45  develop    -> origin/develop
   d637d67..ba81fb2  master     -> origin/master
Updating 5386563..902fb45
Fast-forward

all the remote branches are fetched, but only the branch I'm currently on is merged with its corresponding remote branch.

So I have to do git checkout master ...

Switched to branch 'master'
Your branch is behind 'origin/master' by 106 commits, and can be fast-forwarded.

...and then git pull again, and then switch back to develop, to get the desired result.

I know I can make aliases/scripts that does these steps. But I want to avoid that if possible, as it is error prone and not very efficient.
Edit: ok let me rephrase that. My goal was not to discourage or frown upon script/alias customizing of git. I would just prefer a builtin solution if it exists :)

Answer 1

You can set up an alias that uses git fetch with refspecs to fast-forward merge your branches with just one command. Set this up as an alias in your user .gitconfig file:

[alias]
    sync = "!sh -c 'git checkout --quiet --detach HEAD && \
                    git fetch origin master:master develop:develop ; \
                    git checkout --quiet -'"

Usage: git sync.

Here is why it works:

1. git checkout --quiet HEAD directly checks out your current commit, putting you into detached head state. This way, if you're on master or develop, you detach your working copy from those branch pointers, allowing them to be moved (Git won't allow you to move the branch references while your working copy has them checked out).

2. git fetch origin master:master develop:develop uses refspecs with fetch to fast-forward the master and develop branches in your local repo. The syntax basically tells Git "here is a refspec of the form <source>:<destination>, take <destination> and fast-forward it to the same point as <source>". So the sources in the alias are the branches from origin, while the destinations are the local repo versions of those branches.

3. Finally, git checkout --quiet - checks out the branch you were last on, regardless of whether or not there was a failure in the previous commands. So if you were on master when you ran git sync, and everything succeeds, you'll leave detached head state and check out the newly updated master.

See also my answer to git: update a local branch without checking it out?.

Answer 2

Install git-up. It gives you the command git-up which will pull all local branches in your repository.

Answer 3

git fetch --update-head-ok origin master:master develop:develop

This is a shorter version of @40XUserNotFound answer, beware that it may move your HEAD, be sure you have a clean working directory before running this command.

--update-head-ok does what this answer doing by detaching HEAD, instead it simply tells fetch it's ok to move HEAD (where your working directory is).

Answer 4

It seems that there is no builtin option for git to pull into multiple branches. At least not in version 1.8.0. although @Cupcake's answer is close to it.

However @jjlin's comment made me realize that at least I don't need to pull twice.

So a slightly more efficient sequence would be:

git pull
git checkout master
git merge origin/master
git checkout -

Inevitably I ended up creating an alias, but decided to leave the pull out of it, and focused on just fast-forwarding a different branch.

[alias]
ffwd = "!_() { git checkout $1 && git merge --ff-only origin/$1 && git checkout -; }; _"

Of course, with no testing this alias assumes that I supply a valid name of a ff'able branch as 1st argument, and has undefined behaviour otherwise. It is also not optimal for use-cases with more than two branches, but it will get me what I need for now.

git pull
git ffwd master