git checkout custom_branch && git rebase master

This will update custom_branch with changes from master branch.

Don't forget to make sure master is up to date first. git pull

This is also possible with git checkout custom_branch && git merge master

How I would do this

git checkout master
git pull origin master
git merge test
git push origin master

If I have a local branch from a remote one, I don't feel comfortable with merging other branches than this one with the remote. Also I would not push my changes, until I'm happy with what I want to push and also I wouldn't push things at all, that are only for me and my local repository. In your description it seems, that test is only for you? So no reason to publish it.

git always tries to respect yours and others changes, and so will --rebase. I don't think I can explain it appropriately, so have a look at the Git book - Rebasing or git-ready: Intro into rebasing for a little description. It's a quite cool feature

You can either git merge master or git rebase master.

If the branch has not been distributed to other people, in this case i would prefer git rebase.

Because git rebase makes it as if the changes on the feature branch were made on top of the changes on the master branch, which makes the version graph simpler.

Rebase

Taking the example from the git rebase manual, git rebase master in branch feature:

      A---B---C feature                             A'--B'--C' feature
     /                   --rebase-->               /
D---E---F---G master                  D---E---F---G master

However, git rebase is only suitable when nobody else is working on it, or there will be confusion and extra work for them, because the old commits A, B, C are now replaced by new commits A', B', C', plus F and G that were not there before.

The actual result after git rebase master in branch feature is this:

      ( A---B---C ) feature@{1}
       /
      /       A'--B'--C' feature
     /       /
D---E---F---G master

Commits A, B, C are dangling after the rebase, but are reachable through git reflog feature as feature@{1}.

Merge

If someone has pulled your branch, or you have pushed it somewhere, you should merge into it instead, to avoid confusion and extra work on the other end. See Recovering from upstream rebase.

This is the result of git merge master in branch feature:

      A---B---C feature                    A---B---C---M feature
     /                   --merge-->       /       ,---’
D---E---F---G master                 D---E---F---G master

Alternatively, if you git merge feature in branch master, it would look like this:

      A---B---C feature                    A---B---C feature
     /                   --merge-->       /         \
D---E---F---G master                 D---E---F---G---M master

You can certainly branch off of any branch. If your refactor branch is long-lived, and you need to add a new feature based off it the work you've already done, create feature2 off the refactor branch.

However, those 2 branches are intertwined now. You'll need to regularly pull from refactor into feature2 (in addition to pulling from main into refactor). Your PR from feature2 into refactor will only reflect the diffs between those 2 branches, but when you open a PR from refactor into main you will get see diffs from feature2 as well - something to keep in mind for whoever is reviewing.

In order for the feature2 PR to be as clean as possible, the changes you make in feature2 should be completely unrelated to the changes you're making in refactor. When you start changing the same functions in the same files on the two branches, that means conflicts. Given your use-case though (the feature depends on the work you're doing in the refactoring) this may be unavoidable.

Given all that, I'd caution about having such a long-lived branch (refactor) that you are doing other development on (feature2) at the same time. If this is truly a refactoring, adding in new features can complicate the determination that the refactoring was successful (is a bug due to the refactor or the new feature). So while it is possible to branch off of your refactoring branch, I'd evaluate whether you really want to do that, or focus on wrapping up the refactoring first.

Hi @Ronald Rex , 

Welcome to Microsoft Q&A!

To merge a feature branch into main branch in Visual Studio, you can double-click on the main branch in the branch list.

Then, right-click on the feature branch and select “Merge ‘feature_branch’ into ‘main’”.

For more information, you can refer to: Merge and rebase branches.

Sincerely,

Anna

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