Git merge only the final result of a development branch

Question

If a Git repository structure looks like this:

master: A-C
dev:     \B-D-E

is it possible to merge the development branch into master so that only one commit is added to master, containing all of the changes found in all of the commits in the development branch. So the above structure would merge to look like this:

master: A-C-E'

The E' commit would contain all of the changes from the development branch and only the latest commit message, adding the new feature to master in one tidy commit.

Is this possible in Git? I'm hoping to be able to keep the history of a GitHub repository tidy, as my development branches often contain early commits which are unfinished, unpolished and unfit for human consumption.

Answer 1

The merge part should be easy (see "How to use git-merge --squash?"):

git checkout master
git merge --squash dev

You might have to adjust the commit message though:

git commit --amend -m "<commit message from E>"

(you have other options when doing the merge)

Answer 2

You can achieve this, though it won't be a merge. (Remember: A merge commit has 2 or more parents. E' only has one parent, though: C.)

git rebase -i master dev

• A text editor will open. Change pick to squash for all but the first line, then save the file and close the editor.
• A text editor will open. (Populated with different content.) Edit its content to be the commit message you want for E', then save the file and close the editor.

Then

git checkout master
git merge dev --ff-only
git branch -d dev