/git

git

Really good link with a git cheat sheet: https://education.github.com/git-cheat-sheet-education.pdf

Undo uncommitted changes to a single file

Initial history

M testfile.cs
M textfile.txt

In this case, I accidentally modified textfile.txt and want to undo it without undoing the changes made to testfile.cs.

git checkout -- textfile.txt

Resulting in history:

 M testfile.cs

Undo commit, but keep changes

Initial history

* 9b05a59 (HEAD -> master) Added gello.tt
* ddbf625 Added extra line
* e9667ce Initial commit

The last commit was accidental and we want to undo the commit, but keep the change in the file. (Soft reset)

git reset head^1

Resulting in this history

* ddbf625 (HEAD -> master) Added extra line
* e9667ce Initial commit

And this git status

?? gello.tt

Undo commit, and remove changes

Initial history

* dcb55da (HEAD -> master) Added gello.tt
* ddbf625 Added extra line
* e9667ce Initial commit

The last commit was accidental and we want to undo the commit and the change in the file. (Hard reset)

git reset --hard head^1

Resulting in this history

* ddbf625 (HEAD -> master) Added extra line
* e9667ce Initial commit

And the file changed in the commit is deleted.

Adjust last unpushed commit

Typo in last commit:

* 831133f (HEAD -> master) Addded extra line
* e9667ce Initial commit

Change last commit

git commit --amend -m "Added extra line"

Resulting history:

* ddbf625 (HEAD -> master) Added extra line
* e9667ce Initial commit

Rewrite history of feature branch

Warning - doing this while on a shared feature branch will break the branch for others until they pull the branch again. Sync with your team mates!

Initial history

* 3f27b66 (HEAD -> featurebranch) Again... one more line
* ebd453c Added One More
* 2654273 Added One
* ddbf625 (master) Added extra line
* e9667ce Initial commit

We realize that we want to tag each commit with a Task ID before merge to master.

git rebase -i ddbf

This will let you select between all commits made on the featurebranch. Change the first word on each line from pick to reword, and save/close the window. You will now be prompted to rewrite each commit message. In this example I added #task-32 to each commit message.

* aed630f (HEAD -> featurebranch) Again... one more line #task-32
* b4437e2 Added One More #task-32
* 5db2c4a Added One #task-32
* ddbf625 (master) Added extra line
* e9667ce Initial commit

Git squash

Warning - doing this while on a shared feature branch will break the branch for others until they pull the branch again. Sync with your team mates!

On second thought, I don't want this many commits for this feature branch. I want to squash all commits into one before merge to master. (Using the same example as above)

git rebase -i ddbf

This will open the same window as before, where you get to pick the commits you want to work with. In this example we change pick to squash (or s) for the last two commits, and close the window.

* 6d5e459 (HEAD -> featurebranch) Added One #task-32
* ddbf625 (master) Added extra line
* e9667ce Initial commit

When rebase fails

Undo a rebase that didn't go as you hoped

git reset --hard ORIG_HEAD

Delete all local branches

Delete all local branches except master

git branch | grep -v "master" | xargs git branch -D