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Martin Mlostek
Martin Mlostek

Reputation: 2960

Merging problems with re-created git repository

We have had a big git repository that we have re-created under a new git url. The process was the following

Now when the developers try to merge in their feature/a branch back into main it overwrites some parts of the code as it thinks the changes in the feature branch are newer, while in the old repository they were of course identified as older changes as the full git history was available.

Is there a way to solve this situation so the developers dont run into confusion once they start merging?

Upvotes: 0

Views: 60

Answers (2)

Lunivore
Lunivore

Reputation: 17602

For each feature branch, rebase with the old repo's main branch, assuming that the last commit there is the one from which you took the copy (otherwise rebase with that commit), then copy-paste the code as before.

Now all the commits after that point are genuine changes and should merge just fine.

If you don't have the old repo and can't work with it, you can use git cherry-pick to reapply the commits you want to keep from the feature branch (in your new repo) to a new branch (also in your new repo).

If you just copy-pasted the code across along with the changes you don't want, and it's all bodged into one commit, and you have no access to the old repo, I'm afraid you're out of luck; you will have to choose which changes to apply manually.

Upvotes: 1

j6t
j6t

Reputation: 13377

Say, you had this old history:

a--b--c--d--e--f--g     <-- main
         |\
         | h--i         <-- feature/h
          \
           k--l--m      <-- feature/k
            \
             n--o       <-- feature/n

In the following, I use capital letters to mean a commit whose project state is a copy of the corresponding lowercase letter commit above.

You did this in the new repository:

G          <-- main
|\
| I        <-- feature/h
|\
| M        <-- feature/k
 \
  O        <-- feature/n

Of course, when you now merge a feature into the main branch, all changes from, for example, G to I are considered to be merged, because that is how you set up the history.

What you actually should have done is include all merge bases in the reconstructed history:

D--G         <-- main
|\
| I          <-- feature/h
 \
   K--M      <-- feature/k
    \
     O       <-- feature/n

Now the merges should work as expected.

Upvotes: 2

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