How to amend several commits in Git to change author

Git Problem Overview

I have made a series of commits in Git and I realise now that I forgot to set my user name and user email properties correctly (new machine). I have not yet pushed these commits to my repository, so how can I correct these commits before I do so (only the 3 latest commits on the master branch)?

I have been looking at git reset and git commit -C <id> --reset-author, but I don't think I'm on the right track.

Git Solutions

Solution 1 - Git

Warning: now deprecated in favor of filter-repo.

Rebase/amend seems inefficient, when you have the power of filter-branch at your fingertips:

git filter-branch --env-filter 'if [ "$GIT_AUTHOR_EMAIL" = "incorrect@email" ]; then
     GIT_AUTHOR_EMAIL=correct@email;
     GIT_AUTHOR_NAME="Correct Name";
     GIT_COMMITTER_EMAIL=$GIT_AUTHOR_EMAIL;
     GIT_COMMITTER_NAME="$GIT_AUTHOR_NAME"; fi' -- --all

(split across lines for clarity, but not necessary)

Be sure to inspect the result when you're done, to make sure that you didn't change anything you didn't mean to!

Solution 2 - Git

The interactive rebase approach is pretty nice when used in conjunction with exec. You can run any shell command against a specific commit or all commits in the rebase.

First set your git author settings

git config --global user.name "John Doe"
git config --global user.email [email protected]

Then to reset the author for all commits after the given SHA

git rebase -i YOUR_SHA -x "git commit --amend --reset-author -CHEAD"

This will pop up your editor to confirm the changes. All you need to do here is save and quit and it will go through each commit and run the command specified in the -x flag.

Per @Dave's comment below, you can also change the author while maintaining the original timestamps with:

git rebase -i YOUR_SHA -x "git commit --amend --author 'New Name <new_address@example.com>' -CHEAD"

Solution 3 - Git

To change the author only for the last commit:

git commit --amend --author 'Author Name <author.name@mail.com>' --no-edit

Suppose you only want to change the author for the last N commits:

git rebase -i HEAD~4 -x "git commit --amend --author 'Author Name <author.name@mail.com>' --no-edit"

NOTES

the --no-edit flag makes sure the git commit --amend doesn't ask an extra confirmation
when you use git rebase -i, you can manually select the commits where to change the author,

the file you edit will look like this:

pick 897fe9e simplify code a little
pick abb60f9 add new feature
exec git commit --amend --author 'Author Name <author.name@mail.com>' --no-edit
pick dc18f70 bugfix

Solution 4 - Git

The highest voted answer here is now out of date. Git shows this scary warning when using git filter-branch -

WARNING: git-filter-branch has a glut of gotchas generating mangled history
         rewrites. Hit Ctrl-C before proceeding to abort, then use an
         alternative filtering tool such as 'git filter-repo'
         (https://github.com/newren/git-filter-repo/) instead.

To use the filter-repo -

Install the command, using pip -

pip install git-filter-repo
(Needs git v2.22+ and python v3.5+. Check with git --version && python3 --version)

Fix the commits

Email only

git filter-repo --email-callback '
    return email if email != b"incorrect@email" else b"correct@email"
'

Email and author name

git filter-repo --commit-callback '
    if commit.author_email == b"incorrect@email":
        commit.author_email = b"correct@email" 
        commit.author_name = b"Correct Name"
        commit.committer_email = b"correct@email" 
        commit.committer_name = b"Correct Name"
'

Make sure the indents are there when you paste the command in your terminal. The callback uses python syntax so indents are important.

Read more about filter-repo callbacks here.

Solution 5 - Git

This method was documented by GitHub for this very purpose (though GitHub has since removed it). The steps are:

Open the terminal and make a bare clone of your repo

git clone --bare https://github.com/user/repo.git
cd repo

Edit the following script (replacing OLD_EMAIL, CORRECT_EMAIL, and CORRECT_NAME)

#!/bin/sh

git filter-branch --env-filter '
OLD_EMAIL="[email protected]"
CORRECT_NAME="Your Correct Name"
CORRECT_EMAIL="[email protected]"
if [ "$GIT_COMMITTER_EMAIL" = "$OLD_EMAIL" ]
then
    export GIT_COMMITTER_NAME="$CORRECT_NAME"
    export GIT_COMMITTER_EMAIL="$CORRECT_EMAIL"
fi
if [ "$GIT_AUTHOR_EMAIL" = "$OLD_EMAIL" ]
then
    export GIT_AUTHOR_NAME="$CORRECT_NAME"
    export GIT_AUTHOR_EMAIL="$CORRECT_EMAIL"
fi
' --tag-name-filter cat -- --branches --tags

Copy/paste the script into your terminal and press enter to run it.
Push your changes with git push --force --tags origin 'refs/heads/*' and you're done!

Solution 6 - Git

I believe what you are looking for is git rebase --interactive

It allows you to go reset to an specific commit and then go throw the history changing adding or grouping commits

Here you have an explanation https://web.archive.org/web/20100213104931/http://blog.madism.org/index.php/2007/09/09/138-git-awsome-ness-git-rebase-interactive

Solution 7 - Git

If you're looking for a script, this one came handy for me.

Download the script from GitHub and save it to an easily-accessible location.
Change the permissions of the script file to allow it to execute:

chmod +x changeauthor.sh
Navigate into the repository with the incorrect commit history

cd path/to/repo

Run the script (with or without flags)

../path/to/changeauthor.sh --old-email kaka.ruto@example.com \
    --new-email ruto.kaka@example.com --new-name "Kaka Ruto" --remote origin

Be careful as this will rewrite all history in your current dir repository! Good thing is the script give you warnings and info about what you're about to do

Solution 8 - Git

If you're feeling unsafe about debasing and amending you could do it this way. At the same time you'd also be setting the global config which you probably meant to do anyway.

git reset HEAD~ (undo last commit)

git config --global user.name "Your Name"

git config --global user.email [email protected]

git commit -m "message"

Content Type	Original Author	Original Content on Stackoverflow
Question	pauldoo	View Question on Stackoverflow
Solution 1 - Git	Cascabel	View Answer on Stackoverflow
Solution 2 - Git	Alex	View Answer on Stackoverflow
Solution 3 - Git	Chris Maes	View Answer on Stackoverflow
Solution 4 - Git	charsi	View Answer on Stackoverflow
Solution 5 - Git	stevec	View Answer on Stackoverflow
Solution 6 - Git	Fernando Diaz Garrido	View Answer on Stackoverflow
Solution 7 - Git	Kaka Ruto	View Answer on Stackoverflow
Solution 8 - Git	Edison	View Answer on Stackoverflow