git合并并保留原始回购记录中的历史记录

Question

Originally we only had access to a zip of the source code.

So we downloaded, unzipped, created a git repo and pushed.

So there wasn't any git history except from our initial commit.

Now we have access to the original repo so would like to merge and upgrade.

Here is what I have done so far

Add the original repo

git remote add upstream url_to_their_repo
git fetch upstream

Create a blank branch

git checkout --orphan upgrade
git rm -rf .

Merge their code into the upgrade branch

git merge upstream/theirbranch

Copy our code on top

git merge master

It shows a few conflicts which need to be resolved but when I do

git blame filename

It shows the developer who did our initial commit rather than the original repo history.

Is there a way to just copy the history for changes we have made?

Answer 1

I would rebase my changes on top of the new repository

                    upstream/master
                    |
                    V
A---B---C---D---E---F

G---H---I
        ^
        |
        master

First create a local branch from upstream/master

git branch upstreamMaster upstream/master

Then rebase your changes onto upstreamMaster , but omit your first commit. Since the first commit contains all files (unzipped project was committed) it will lead to conflicts. Furthermore you only need your changes so start at commit H .

git rebase --onto upstreamMaster H master

You can use

git log --pretty=format:%H master |tail -1

to find the first commit of master.

After the rebase your repository will look like this

                    upstream/master
                    |
                    V
A---B---C---D---E---F---H---I
                    ^       ^
                    |       |
       upstreamMaster       master

Now you can fast forward the upstreamMaster

git checkout upstreamMaster
git merge master