ChatGPT解决这个技术问题 Extra ChatGPT

Git pull a certain branch from GitHub

I have a project with multiple branches. I've been pushing them to GitHub, and now that someone else is working on the project I need to pull their branches from GitHub. It works fine in master. But say that someone created a branch xyz. How can I pull branch xyz from GitHub and merge it into branch xyz on my localhost?

I actually have my answer here: Push and pull branches in Git

But I get an error "! [rejected]" and something about "non fast forward".

Any suggestions?

what is the actual command you're running?
It is fetch that can fail with 'non fast forward' message. Did you modify remote-tracking branch (origin/xyz), or was the branch rewound / rewritten in remote repository? Youmight need to use "git fetch origin --force", but please read documentation before doing it.
The remote could be, for example, a github URL, with a selected branch.. (see comment to Cabri's answer)

m
mipadi

But I get an error "! [rejected]" and something about "non fast forward"

That's because Git can't merge the changes from the branches into your current master. Let's say you've checked out branch master, and you want to merge in the remote branch other-branch. When you do this:

$ git pull origin other-branch

Git is basically doing this:

$ git fetch origin other-branch && git merge other-branch

That is, a pull is just a fetch followed by a merge. However, when pull-ing, Git will only merge other-branch if it can perform a fast-forward merge. A fast-forward merge is a merge in which the head of the branch you are trying to merge into is a direct descendent of the head of the branch you want to merge. For example, if you have this history tree, then merging other-branch would result in a fast-forward merge:

O-O-O-O-O-O
^         ^
master    other-branch

However, this would not be a fast-forward merge:

    v master
O-O-O
\
 \-O-O-O-O
         ^ other-branch

To solve your problem, first fetch the remote branch:

$ git fetch origin other-branch

Then merge it into your current branch (I'll assume that's master), and fix any merge conflicts:

$ git merge origin/other-branch
# Fix merge conflicts, if they occur
# Add merge conflict fixes
$ git commit    # And commit the merge!

No, the problem is with fetching, not with merge step.
Normally, remotes are set up such that fetches are forced, even if they don't result in a fast-forward commit, so it shouldn't occur on fetch unless the OP changed something with the usual configuration. The fast-forward issue can occur during fetch or merge. What makes you say that the problem is definitely in fetching, and not in merging?
I follow these steps (fetch, merge). Git tells me there's nothing to do. When I try to commit, it falls over moaning about fast-forwards.
@mipadi I had same issue as Jean and, while I can't say the remote is setup in the non default way you've mentioned I can say using git fetch -f have fixed my issue! Thanks!
This merges remote branch xzy into local branch master, which is not what was implied by the original question; "How can I pull branch xyz from GitHub and merge it into branch xyz on my localhost?"
S
StayOnTarget

Simply track your remote branches explicitly and a simple git pull will do just what you want:

git branch -f remote_branch_name origin/remote_branch_name
git checkout remote_branch_name

The latter is a local operation.

Or even more fitting in with the GitHub documentation on forking:

git branch -f new_local_branch_name upstream/remote_branch_name

If you get 'Not a valid object name: 'origin/remote_branch_name', do 'git fetch origin' first.
fatal: Cannot force update the current branch.
A
Abu Shoeb

A safe approach is to create a local branch (i.e. xyz) first and then pull the remote branch into your locals.

# create a local branch
git checkout -b xyz

# make sure you are on the newly created branch
git branch

# finally pull the remote branch to your local branch
git pull origin xyz

Here is the syntax that could pull a remote branch to a local branch.

git pull {repo} {remotebranchname}:{localbranchname}

git pull origin xyz:xyz

Perfect! I just didn't know that syntax: git pull {repo} {remotebranchname}:{localbranchname}. Question, if that pull doesn't work (maybe someone's updated the branch and there would be merge conflicts) what are my options?
I'm downvoting this because it attempts to merge the remote branch into your current branch (e.g. master). This is not what most people want to do, and it's not what the OP asked for. The answer by @mohit is the correct choice.
Phrogz - looks like this behavior changed in recent versions of Git. I used this before and it worked perfectly well.
The answer is seriously misleading!!! I applied the answer without noticing @Phrogz 's comment and now suffering from the problem s/he mentioned. Either which branch it tries to merge should be expressed explicitly or the answer should be deleted !!!!
@Phrogz,@Letitbe which command did you try? I can change the answer accordingly. Never had the issue of pulling it into master.
P
Peter Mortensen

The best way is:

git checkout -b <new_branch> <remote repo name>/<new_branch>

After creating a new "dev" branch on github, and trying the above, I got the following error message: "fatal: origin/dev is not a commit and a branch 'dev' cannot be created from it" Solution was to "git fetch" per Bradley Flood's solution below, and then re-running mohit's answer.
B
Bradley Flood

git fetch will grab the latest list of branches.

Now you can git checkout MyNewBranch

Done :)

For more info see docs: git fetch


it worked fine git fetch, then git checkout remoteBranch
P
Peter Mortensen

I am not sure I fully understand the problem, but pulling an existing branch is done like this (at least it works for me :)

git pull origin BRANCH

This is assuming that your local branch is created off of the origin/BRANCH.


This will pull the branch into your current local branch, so when you are on dev and to git pull origin feature it will pull the feature branch into dev. The person who asked the question wants to make a new branch feature and pull into this branch
but first you need to do git checkout -b xyz then you do git pull origin xyz
A
Adrien Renaud

Simply put, If you want to pull from GitHub the branch the-branch-I-want:

git fetch origin
git branch -f the-branch-I-want origin/the-branch-I-want
git checkout the-branch-I-want

a
anatoly techtonik

This helped me to get remote branch before merging it into other:

git fetch repo xyz:xyz
git checkout xyz

F
Frádely Diloné

for pulling the branch from GitHub you can use

git checkout --track origin/the-branch-name

Make sure that the branch name is exactly the same.


V
Vicky

I did

git branch -f new_local_branch_name origin/remote_branch_name

Instead of

git branch -f new_local_branch_name upstream/remote_branch_name

As suggested by @innaM. When I used the upstream version, it said 'fatal: Not a valid object name: 'upstream/remote_branch_name''. I did not do git fetch origin as a comment suggested, but instead simply replaced upstream with origin. I guess they are equivalent.


Worked for me. Thanks
K
KARTHIKEYAN.A
git pull <gitreponame> <branchname>

Usually if you have only repo assigned to your code then the gitreponame would be origin.

If you are working on two repo's like one is local and another one for remote like you can check repo's list from git remote -v. this shows how many repo's are assigned to your current code.

BranchName should exists into corresponding gitreponame.

you can use following two commands to add or remove repo's

git remote add <gitreponame> <repourl>
git remote remove <gitreponame>

P
PKV

you may also do

git pull -r origin master

fix merge conflicts if any

git rebase --continue

-r is for rebase. This will make you branch structure from

        v  master       
o-o-o-o-o
     \o-o-o
          ^ other branch

to

        v  master       
o-o-o-o-o-o-o-o
              ^ other branch

This will lead to a cleaner history. Note: In case you have already pushed your other-branch to origin( or any other remote), you may have to force push your branch after rebase.

git push -f origin other-branch

t
titleLogin

you can try with

git branch -a

or git fetch to get latest list of branches.

git checkout theBranch //go in to the branch

git checkout -b "yourNewBranch" // to work in your own branch in base "theBranch"