git + github auto merge commit + pull request

Question

I forked repo vanilla via github interface to vanilla_copy , after that I do: git clone vanilla_copy , after some time I do git pull and get one new commit feature A , and my history now looks like

Merge remote-tracking branch 'upstream/master'
feature A

after I commit something my self it become:

feature created by me
Merge remote-tracking branch 'upstream/master'
feature A

At now I want to create pull request to vanilla ,

1. is it normal that my commit feature created by me have parrent that not exists in vanilla repo?

2. How I should use git to not create this auto merge commit , use git pull --rebase or track vanilla/master via vanilla_copy/upstream and use git rebase branch or some other mechanizm?

3. How should I remove this existing merge commit? Should I remove commit via git rebase -i and then git push -f as described here: Delete Github commit history ?

Answer 1

In order to keep git repos easy to navigate, i squash my commits down to a few, or one, discreet changesets before submitting a pull request. Fixing a bug will usually only need one commit, while a larger feature might contain a couple of separate improvements that is easier to track through different commits.

Once you have rebased your work on top of the latest state of the upstream master, you may have several commits related to the issue you were working on. Once everything is done, squash them into a single commit with a descriptive message, like "Issue #100: some bugfix."

To squash four commits into one, do the following:

$ git rebase -i HEAD~4

In the text editor that comes up, replace the words "pick" with "squash" next to the commits you want to squash into the commit before it. Save and close the editor, and git will combine the "squash"'ed commits with the one before it. Git will then give you the opportunity to change your commit message to something like, "Issue #100: Fixed some bug."

Important : If you've already pushed commits to GitHub, and then squash them locally, you will have to force the push to your branch.

$ git push origin branch-name --force

Helpful hint: You can always edit your last commit message, before pushing, by using:

$ git commit --amend

See also:

Git Book Chapter 6.4: Git Tools - Rewriting History