git - How to avoid merge-commit hell on GitHub/BitBucket

Question

We're ending up with a lot of commits like this in our repo:

Merge branch 'master' of bitbucket.org:user/repo

This happens every time a developer syncs his/hers local fork to the top-level repo.

Is there anyway to avoid this merge-commit hell from cluttering all the repo log? Can one avoid them when initiating the pull-requests in some way?

I know I can do git rebase if this is done in my local VM only, is there any equivalence in the GitHub/BitBucket UI?

How do you guys do it?

Answer 1

Rebase Feature Branches Before Merging

If you want to avoid merge commits, you need to ensure all commits are fast-forwards. You do this by making sure your feature branch rebases cleanly onto your line of development before a merge like so:

git checkout master
git checkout -b feature/foo

# make some commits

git rebase master
git checkout master
git merge --ff-only feature/foo

Rebase also has a lot of flags, including interactive rebasing with the -i flag, but you may not need that if you're keeping things as simple as possible and want to preserve all of your branch history on a merge.

Use the --ff-only Flag

Aside from rebasing, the use of the --ff-only flag will ensure that only fast-forward commits are allowed. A commit will not be made if it would be a merge commit instead. The git-merge(1) manual page says:

--ff-only

Refuse to merge and exit with a non-zero status unless the current HEAD is already up-to-date or the merge can be resolved as a fast-forward.