git pull --rebase upstream & git push origin rejects non-fast-forward?

Question

I've implemented classic OSS maintainer/contributor git workflow for a company project on github, however one edge case produces some weird results that I'm not sure how to get around.

Lets say there is a typical project that I forked and added upstream remote to keep it up to date.

git clone [email protected]:kozhevnikov/<project>.git
git remote add upstream [email protected]:<company>/<project>.git

For the purposes of this example this fork is behind by a few commits.

git reset --hard HEAD~5 && git push --force

I work on this fork and push some commits, before pushing my last commit and creating a pull request I update my fork's clone to make sure there are no conflicts.

touch foo && git add foo && git commit -m foo && git push
touch bar && git add bar && git commit -m bar

git pull --rebase upstream master

From github.com:<company>/<project>
 * branch            master     -> FETCH_HEAD
First, rewinding head to replay your work on top of it...
Applying: foo
Applying: bar

Now, when I try to push to my fork I get rejected.

git push

To [email protected]:kozhevnikov/<project>.git
 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to '[email protected]:kozhevnikov/<project>.git'
To prevent you from losing history, non-fast-forward updates were rejected
Merge the remote changes (e.g. 'git pull') before pushing again.  See the
'Note about fast-forwards' section of 'git push --help' for details.

What should I do next? All I want is for the pull request to contain foo and bar commits, however...

When I pull, pull request contains duplicate foo commits as well as extra merge one.

git pull
Merge made by the 'recursive' strategy.

git push

On github pull request looks like this.

Showing 4 unique commits by 1 author.
12345  
kozhevnikov  foo    4 minutes ago
67890  
kozhevnikov  foo    4 minutes ago
abcde  
kozhevnikov  bar    2 minutes ago
fghij  
kozhevnikov  Merge branch 'master' of github.com:kozhevnikov/<project>    just now

When I git pull --rebase instead of pull, at best it'll include other people's commits into my pull request (those from reset), and at worst it gives me merge conflicts.

When I git push --force without any pull or --rebase it works perfectly, however I'm very uneasy in saying to everyone use the force or making it part of standard workflow as I can imagine few people or a small subteam collaborating on a single fork and stepping on each other's toes with forced push.

Any ideas? What am I missing?

Answer 1

When you

git pull --rebase upstream master

you are rewriting your own history, since you are rebasing your master branch on the updated upstream repository. When you push your rebased repo to your fork git complains. You need to push with --force

git push --force origin master