将较新的Git仓库附加到较旧的仓库以合并两个历史记录

Question

I've got two related git repositories on GitHub that should really be one. How do I combine both projects into one project, in a way that satisfies the following context:

• Each repo currently only has a master branch.
• A is the older repo, B is the newer repo.
• A is the canonical repo (ie: repo A has the name that I ultimately want this tool to be called, so I want all future work, after B has been appended to A, to be done in repo A).
• After B has been appended to A, A should exist, B should be deleted.
• I don't want to put one repo as a subdirectory of the other, I want to combine the two repos as if they were one repo all along.
• I want this change to the git history of A to be permanent so that folks don't have to pull refs, but instead just clone the updated repo A and get everything as expected.
• There are 3 similar files between the two repos: .gitignore , readme.md , and package.json .

Answer 1

You can:

• merge the two repository history as described here
• once the commits of both repositories are interlaced, you can deal manually with the three common files in order to fix their content.

Answer 2

Here is a clean way to do it:

From your local A repository

git remote add b https://github.com/your-username/your-b-repo.git
git fetch b
git checkout -b b-master b/master
git rebase master
# fix conflicts if any
git checkout master
git merge b-master
git branch -d b-master

Explanation

1. Add your secondary remote repository called b to the local primary repository
2. Fetch everything from it
3. Create a new local branch that matches the b/master called b-master and checkout to it
4. Place everything you did in the B repository after everything you did in the A repository using the rebase command
   1. Fix the conflits during the rebase
5. Checkout your master branch (on A)
6. merge the master branch (A) to the b-master branch (B)
7. Delete the now useless b-master branch