Remove changes to file in old, already pushed, git commit?

Question

I have an old commit, A. When I committed A, I changed 2 files: F1 and F2. I want to change A, so it only modifies file F1. I want to commit F2 separately. I do not want to delete F1 from my git repository.

I tried doing this by

git rebase -i HEAD~3 // The exact number doesn't matter, I just change "pick" to "edit" next to A
git reset HEAD^ // unstage all changes
git add F1 // don't add F2, we want to commit it separately
git rebase --continue

However, this gives the error

F2: needs update
You must edit all merge conflicts and then
mark them as resolved using git add

I solve the problem by doing git rebase --skip

However, this removes commit A from the git history completely.

What am I doing wrong?

I looked at other posts on SO, and tried the solutions, but they didn't work.

Have you already pushed this branch to the remote, and is it already shared? If so, then you should probably _not_ be attempting to rewrite the branch history via git rebase. — Tim Biegeleisen, Nov 11 '19 at 05:12
No one else has pulled this branch yet. Also, once I merge this branch, I can delete it, so I imagine there shouldn't be an issue? — Foobar, Nov 11 '19 at 05:13
https://stackoverflow.com/questions/32315156/how-to-inject-a-commit-between-some-two-arbitrary-commits-in-the-past — Tim Biegeleisen, Nov 11 '19 at 05:21

David Sugar · Answer 1 · 2019-11-11T15:17:21.550

3

Here is how I would do this:

git rebase -i HEAD~3 //Change "pick" to "edit" for commit to change
git reset HEAD^ -- F2 //reset F2 to previous version in staging area
git commit --amend //replace current commit with F1 change only
git add F2 // add new F2 back to staging area
git commit //commit F2 in a separate commit
git rebase --continue

Note that this, as all rebases, rewrites history, and so should only be done if the commits have not yet been pushed to a public repository.

edited Nov 11 '19 at 15:17

answered Nov 11 '19 at 14:26

David Sugar

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Use `git status` liberally to double check what is going on at all stages. – David Sugar Nov 11 '19 at 14:27

score 0 · Accepted Answer · answered Nov 11 '19 at 05:28

I almost did what @Tim's post suggested, except I had to add in 1 command. Here's what I did:

git rebase -i HEAD~3 // The exact number doesn't matter, I just change "pick" to "edit" next to A
git reset HEAD^ // unstage all changes
git add F2
git commit -m "Add F2"
git add F1
git commit -m "Add F1"
git rebase --continue

The git reset HEAD^ was not mentioned in the linked post.

Remove changes to file in old, already pushed, git commit?

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