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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 removing.

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

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

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repair it, I'm using git checkout 34F0. Enough of the last commit ID should do it. Oh, no, I

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have a detached head. What is going on? Well, the problem is that I have repaired the file and I

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have not used any branches and git doesn't like that very much. And we need to fix it. How do

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we do that? Well, first, I'm going to use git branch minus minus show current. And that is

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showing me nothing. And why is it not showing me nothing? That's because I'm detached. I'm not

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in a current branch. And that is why git is confused. Now I'm going to use git lev log. And

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there we can see that in the reference log, I was moving from main to 34F0. So from here, I'm

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learning that the last branch I was in was main. And now I'm going to use git switch main. And

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there it is telling me that the previous branch had minor changes, and it switched to branch new.

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And when I use ls, well, I'm back in my main branch, but my file is not. My file is still in

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the old branch. So what is the hash of the old branch? That's the 34F0. And I need to get my

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file from 34F0 into my current environment. And how am I going to do that? Well, I'm going to use

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git restore minus minus source is 34F0 minus minus group, because that is the name of the file that

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I want to restore. Then I'm using git add group to get my file back and git status to see what is

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going on. And there we can see that it's back as a new file. And now that it is back as a new file, I

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can use git commit to finally get it definitely back. So git commit minus m getting the file back

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or maybe more specific, getting the accidentally removed file back. And now my file is back. And

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the only thing I still have to do is my my git push, as you can see, and it's now up on the remote

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as well.