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Do you know that feeling? Oh no, what have I done? Every now and then it happens to everybody.

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You need to undo the changes that you have just committed. Now the ability to undo a

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change on GitHub depends on the current state of the modification. If a file is staged but

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not yet committed, it's easy. Use git restore minus minus staged on the filename. So git

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rm filename git status will show you the removed filename which is still in the staging area

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and to get it out of the staging area back in the normal environment, git restore will

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do it for you. If a file has already been committed, it's a bit harder. You need git

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log and identify the commit by the commit message. And next you use the commit hash

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or a part of it to revert the transaction using git checkout. And do make sure if you

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are going for this procedure that you revert to the last commit where you still had the

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file. Not always easy to find out which that was. Let me demonstrate. So I'm in my git

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repo and I'm going to git rm group. And then git status is giving me a deleted file. Next

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I'm going to use git commit minus m removing still only a message and now the file has

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been deleted. And git status is showing nothing anymore. Now to make it even worse, I'm going

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to use git push to push the change to the remote. And now I want to use a git log minus

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minus followed by the name of the removed file. So git log minus minus group is showing

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what? Well, it's showing this guy. Here we have the commit. The commit message was

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removing. Do you see how important these commit messages are, by the way? And here we have

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the previous one with the minor changes. So that is the one that I'm going to need. And

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in order to repair it, I'm using git checkout 34F0. Enough of the last commit ID should

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do it. Oh, no, I have a detached head. What is going on? Well, the problem is that I have

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repaired the file and I have not used any branches and git doesn't like that very much.

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And we need to fix it. How do we do that? Well, first, I'm going to use git branch minus

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minus show current. And that is showing me nothing. And why is it not showing me nothing?

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That's because I'm detached. I'm not in a current branch. And that is why git is confused.

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Now I'm going to use git lev log. And there we can see that in the reference log, I was

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moving from main to 34F0. So from here, I'm learning that the last branch I was in was

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main. And now I'm going to use git switch main. And there it is telling me that the

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previous branch had minor changes, and it switched to branch new. And when I use ls,

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then I can see my... Okay, so what is going on? Well, I'm back in my main branch, but my

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file is still in the old branch. So what is the hash of the old branch? That's 34F0. And I

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need to get my file from 34F0 into my current environment. And how am I going to do that?

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Well, I'm going to use git restore. Minus minus source is 34F0. Minus minus group, because

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that is the name of the file that I want to restore. Then I'm using git add group to get my

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file back and git status to see what is going on. And there we can see that it's back as a new

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file. And now that it is back as a new file, I can use git commit to finally get it definitely

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back. So git commit minus m getting the file back, or maybe more specific, getting the

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accidentally removed file back. And now my file is back. And the only thing I still have to do is

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my my git push, as you can see, and it's now up on the remote as well.