(one more) change git history to add very first commit

Question

I am changing the code of another (not git). I loaded the original, completed my modifications and jumped from the gun and made the modified version my first fixation. It was a mistake, I had to add the source code downloaded as the first commit.

Then, to add insult to the injury, I added the source code as a branch of my first edit .. In other words, now this is a big mess :(

Simply put, what I have is like the blue graph below. C5 is the real source code, C1, C2-C6 are my incremental modifications (C4 is redundant). I'd rather greens be my story.

Any ideas on how to change the story to do this?

Thank you, many,

tricky

Answer 1

I did this completely on the command line, but I am going to insert screenshots from SourceTree to illustrate what is happening.

First get the first 7 or 8 digits of the commit identifier (50da9c3) from transaction C5 and add to your clipboard or textedit or something else - you'll need it later

To confirm, here is our initial state:

Here are the steps you need to complete so that you can:

Create a new branch without roots to start the construction, it completes the work with the named base.

git symbolic-ref HEAD refs/heads/base 

Now delete all files and directories from git

 git rm --cached -r . 

Now that all untracked files remove them from the local working directory

 git clean -d --force 

Now create a commit without anything (this will be a commit on which everything will be built).

 git commit --allow-empty -m'Initial Commit' 

Your tree should look like this:

Now the cherry selects c5 commit (what you had on the clipboard)

 git cherry-pick 50da9c3 

Now reinstall the main branch to the base branch

 git rebase --onto base --root master 

Now you can delete the base and c4-c5 branches

 git branch -d base 

 git branch -D c4-c5branch 

Keep in mind that “Initial commit” is an empty commit without files, so don't be fooled. C5 commit is actually the first content-based commit.