Git: How to squash all commits on branch

I make new branch from master with:

git checkout -b testbranch

I make 20 commits into it.

Now I want to squash those 20 commits. I do that with:

git rebase -i HEAD~20

What about if I don't know how many commits? Is there any way to do something like:

git rebase -i all on this branch

Solution 1:

Another way to squash all your commits is to reset the index to master:

git checkout yourBranch
git reset $(git merge-base master $(git branch --show-current))
git add -A
git commit -m "one commit on yourBranch"

This isn't perfect as it implies you know from which branch "yourBranch" is coming from.
Note: finding that origin branch isn't easy/possible with Git (the visual way is often the easiest, as seen here).

Note: git branch --show-current has been introduced with Git 2.22 (Q1 20219).

EDIT: you will need to use git push --force

Karlotcha Hoa adds in the comments:

For the reset, you can do

git reset $(git merge-base master $(git rev-parse --abbrev-ref HEAD)) 

[That] automatically uses the branch you are currently on.
And if you use that, you can also use an alias, as the command doesn't rely on the branch name.

Solution 2:

Checkout the branch for which you would like to squash all the commits into one commit. Let's say it's called feature_branch.

git checkout feature_branch

Step 1:

Do a soft reset of your origin/feature_branch with your local main branch (depending on your needs, you can reset with origin/main as well). This will reset all the extra commits in your feature_branch, but without changing any of your file changes locally.

git reset --soft main

Step 2:

Add all of the changes in your git repo directory, to the new commit that is going to be created. And commit the same with a message.

# Add files for the commit.
git add ...
git commit -m "commit message goes here"

Solution 3:

What you're doing is pretty error-prone. Just do:

git rebase -i master

which will automatically rebase only your branch's commits onto the current latest master.

Solution 4:

Another simple way to do this: go on the origin branch and do a merge --squash. This command doesn't do the "squashed" commit. when you do it, all commit messages of yourBranch will be gathered.

$ git checkout master
$ git merge --squash yourBranch
$ git commit # all commit messages of yourBranch in one, really useful
 > [status 5007e77] Squashed commit of the following: ...

Solution 5:

Assuming you were branching from the master, you don't need to enter yourBranch into the reset step all the time:

git checkout yourBranch
git reset --soft HEAD~$(git rev-list --count HEAD ^master)
git add -A
git commit -m "one commit on yourBranch"

Explanation:

• git rev-list --count HEAD ^master counts the commits since you made your feature branch from the master, f.ex. 20.
• git reset --soft HEAD~20 will make a soft reset of the last 20 commits. This leaves your changes in the files, but removes the commits.

Usage:

In my .bash_profile I have added an alias for gisquash to do this with one command:

# squash all commits into one
alias gisquash='git reset --soft HEAD~$(git rev-list --count HEAD ^master)'

After reseting and committing you need to do a git push --force.

Hint:

If you're using Gitlab >= 11.0 you don't need to do this anymore as it has a squashing option when merging branches.