17 Ways to Undo Mistakes with Git

Disaster summary: It's not that you messed up completely. It's just that some parts of your changes aren't as brilliant as they seemed at first. That's no reason to throw the baby out with the bath water: let's keep the changes that make sense and discard those that don't!

Disaster summary: You had a feeling this morning, and it was correct: you should have stayed in bed. Because you clearly coded yourself into a dead-end street. So let's just discard all uncommitted work and return the project to its last committed state.

Disaster summary: Word is on the street that you commit faster than your shadow. While you normally take that as a compliment, in this case it's more of a problem: because you littered the last commit's message with typos. Let's clean this up and make it so that no one ever hears about this!

Disaster summary: Recently, it became clear that you and your old friend, commit a4f780b, don't get along so well anymore. Unfortunately, he's been in your code base for quite a while now. So instead of "deleting" him from your commit history, let's neutralize him in a friendly way: by creating a new commit that reverts his effects!

Disaster summary: There was a time when everything was wonderful in your repository, when everything worked. Here's to these good old days! Luckily, you can turn back time and reset your project to an old revision.

Disaster summary: Not everything was better in the old days! Just this one particular file, that you now long to restore from a previous revision. Here's how!

Disaster summary: Using "git reset" is a wonderful way to get rid of some unwanted commits. But it's also a wonderful way to get yourself into trouble - if you got rid of the wrong commits! But chin up! You can undo even that!

Disaster summary: You were absolutely sure that you wouldn't need a certain branch (and all its valuable commits) anymore when you deleted it. But on second thought... let's see if we can restore it!

Disaster summary: You've worked busily on a new feature and solemnly made the first commit - although you haven't created a separate feature branch for it. Let's get that new feature commit off of the "master" branch and move it to its own feature branch!

Disaster summary: It happens to the best: you thought you were on the right branch, but you really weren't. Here's how to move your commit from the wrong branch to the right one.

Disaster summary: Sometimes you hit RETURN and notice instantly that you just made a typo in your commit message. No problem: Git's "amend" feature is here to help! Other times, however, it takes days and weeks before you notice your spelling mistakes - and yet there's still a way to save your good reputation!

Disaster summary: Buried deep inside your commit history, there's a commit that just shouldn't be there. Let's make it look like it never happened!

Disaster summary: Committing in small, granular doses is actually a virtue. But of course there can be "too much of a good thing". If you've overdone it and want to combine multiple commits into one: here's how!

Disaster summary: There's this commit. It's almost perfect. But not quite. So let's add the missing change or correct the little mistake - and make it look like the commit was perfect from the beginning!

Disaster summary: What if you could crack that existing old commit open and change it any way you like? Add more changes, discard others, and make as many commits from it as you want. Help yourself: here's how this works!