如何使用master的更改更新远程分支

Question

I've done a fair bit of research/practices on rebasing and merging our remote branches but I am unable to find a solution that ultimately doesn't result in duplicate commits or a non-fast forward push of the remote branch. Here's what I'm trying to do.

We have two branches, master (tracking origin/master ) and hebe (tracking origin/hebe ). hebe was branched off of master appropriately a month ago. There are several developers working on both branches daily.

master is continuing to be maintained and has several bug fixes in common code that should be reflected/updated in the hebe branch. However none of the new code in hebe should make its way into master

I've tried:

git rebase master hebe

Which seemed from the log to be exactly what we wanted, hebe commits were on top of the latest master , however when I attempt to push hebe it resulted in a warning of a non-fast forward push of origin/hebe .

Or perhaps we are approaching this from the wrong direction and submodules would be the appropriate solution?

Answer 1

You should only rebase in very very very rare cases branches which are already pushed and shared with others since you rewrite the history and thus change the sha's of the commits. This results in your mentioned duplicate commits because a different sha means a different commit for git.
In your case it is better to merge the master with

$ git checkout hebe
$ git merge master
$ git push origin hebe

With this you merge all changes from master into hebe but nothing gets back to master and all shas stay the same. Merging will create an so called merge commit instead (if no fast-forward merge is possible).

Because it is so important and leads to so many confusion, I have to say this again on the end: Never rebase already shared branches unless you are absolutely sure what you are doing.

I deeply recommend reading the third chapter of the following (free online available) book http://git-scm.com/book to get a better understanding of how merging/rebasing works