Tag Archives: git

Magic rebase and (re-) format

If you like clean coherent formatted code, you may already use something like clang-format and git hook to ensure format when commit

If you like clean history, you might use a lot of rebase.

Sometimes during conflit, format is lost, but it’s pita to fix it afterwards without introducing some commit out of the clean history

Update 2022-05-10

I have switch to pre-commit.ci to perform pre-commit hook and formating, applying the same principle, I run

git rebase --strategy-option=theirs -x 'git reset --soft HEAD~1 && \
git commit -C HEAD@{1}' origin/master 

Which reset and reapply commits, hence triggering pre-commit hook. Then conflict resolution is nearly the same, I use the following oneliner to fix all possible conflicts

git add -u && git commit -C HEAD@{1} && \
git rebase --continue          

Older version

I use run-clang-format script with rebase and exec. This will stop rebase if format is not respected

git rebase --exec "./run-clang-format.py -r -i \
--style file --extensions inl,cpp,hpp src/" \

When it stops, you can examine the situation with

git status
git diff

Once everything looks good (in case of conflict, simply use remote, and reformat)

git add -u && \
git commit -m"fix format" && \
git rebase --continue

Then rebase -i again so you can squash/fix all “fix format” commits with their immediate ancestor.

TODO : explain a bit more

Git: cleaning a branch before a PR, and merge back the clean history to the messy WIP branch

Sometimes, I have a branch with a new feature I work on, call it Feature_mess.

At some point I want to show this feature to colleagues, so I want to have a clean history, and remove some WIP stuff

To this end :

git checkout Feature_mess
git checkout -b Feature_clean
git rebase -i Feature_clean master (or whatever base you want)

Cleanup history here, remove crappy things, merge a lot of commits, rewrite history !
Now to benefit from this clean history as a base of Feature_mess

git branch temp Feature_mess
git checkout temp
git reset --soft Feature_clean

Now you are in the state of mess, with the history of cleanup, you can check diff and then

git commit

Et voilĂ  !

More information on git reset here : https://gist.github.com/tnguyen14/0827ae6eefdff39e452b