How to squash commit when approve merge request, gitlab

Question

I have two branches master and release at gitlab.

At release branch, I hope it will only have commit message like: v0.1.0, v0.1.1.

Say after I finished developed v0.1.0, I have have several feature and bugfix commits in master say

c1. bugfix1
c2. feature1 
c3. feature2

I will create merge request in gitlab from master to release, but I hope to make these three commits into one v0.1.0, and squash c1 c2 c3.

Now , in my existing settings, I will have 4 commit messages:

Merge breanch 'master' into release
c1
c2
c3

Is there a way to squash it when I approve at gitlab so that there message will squash into:

 v0.1.0

Please note that these two branch are all proteced branches, and if possible I hope there will be NO git command on release and master branch , and only gitlab operations

Answer 1

git checkout release
git merge --squash master
git commit -m "Suitable Message of your choice"

This will take all the commits from the master branch, squash them into 1 commit and then merge it with your release branch.

Answer 2

The merge commit is only one commit, but it seems you have fallen into the "fast forward" trap. That is, on your merge, git has decided that master is part of the direct ancestry of release, and then just "fast forwarded" your changes on top of release. This, then, looks like what you describe.

To solve this, add the --no-ff option on your merge:

git checkout release
git merge --no-ff master

You will, then, have exactly one commit on your release branch; you can edit the commit message to contain your release version.

Answer 3

You can use git rebase to squash commits.

In your case, it should be git rebase -i HEAD~3.

See http://gitready.com/advanced/2009/02/10/squashing-commits-with-rebase.html

Answer 4

In case you are seeing this message on GitLab graphical interface, like this:

Just follow these steps from your MR link:

Edit > Merge options: uncheck "Squash commits when merge request is accepted" option.

After that, merge should happen on Gitlab.