Hi

I'm Brian.

Let's talk about...

git rebase

It's scary.

The Problem

hard to read history:

Commits out of order
Comments are worthless
Merge commits are in the way and don't add anything
Hard to see why code was introduced, makes debugging difficult

asdf, fix stuff, .

worthless messages

why?

probably because

Let's look at some more quotes

(commit messages)

"Indentation"

— Serj Shine

"mroe"

— Lu Zou

"remove unused constant"

— Shehan Perera

"attempt to fail Jenkins again"

— Shaun Shapiro

"..."

— Maria Zhao

"oops missed"

— Ankit Gupta

"vcr"

— everyone

What Can We Do?

Let's Squash Some of These Messy Commits

Count number of items we are working with in `git log`, use this for the following command

git rebase -i HEAD~4

squash

keep the first 'pick' and change the rest of the ones we want to squash to 's' or 'squash'

[esq] :wq

Next you see a screen where you can a chance to correct your lazy messages

Enter a decent commit message for the sqashed commit

[esq] :wq

try including the jira number :)

I just really want to include this image.

Updated commit history

git log

Still kinda ugly though

now two comments about the same thing separated by other commits

git log

Reorder Commits

`git rebase -i HEAD~4`

[esq] :wq

Commits reordered

[esq] :wq

Woot!!

git rebase -i HEAD~2

choose item(s) to be squashed

[esq] :wq

Success!

But... how could we have prevented having to reorder the commits?

'cause that part was hard :(

Don't `git merge development`

instead:

Use `git pull --rebase origin development`

what does this do?

rewinds the git playhead back
pulls the changes from remote branch
rewrites your changes at the end
makes happy

Let's try it

git log

git pull --rebase origin development

remove commits that are not in development, pull changes from development, reapply our commits at the end.

Updated git log

Looks like there were at ton of commits we forgot to reorder and squash

`git rebase -i HEAD~20`

select commits to squash

[esq] :wq

fix commit message

[esq] :wq

Final Commit History

`git push -f origin bk-save-searches-modal`

You may have noticed that the last commit has the wrong author, that's because I squashed my commits into one of Maria's. Now she gets all the credit for my hard work.

Amend Author

git commit --amend --author "Brian Kulyk <brian.kulyk@move.com>"

PR Merge Conflicts

When submitting my PR, I was warned about a merge conflict that needed to be dealt with manually. We can use rebase to fix this too.

git pull --rebase origin development

conflict

`git status` to see conflicted files

resolve the conflict manually

`git add .`
git rebase --continue`

Done

Notice there is no extra merge commit, which is good... 'cause those are gross.

Remember

use `git pull --rebase`