That just resets to your last local commit. To sync back up to the remote, you need at least do a git reset origin/HEAD --hard (and capitalization matters, I don't know why).
But that doesn't work if you rewrote history in some way (I'm not sure why that's even possible). In that case your local git can get pretty messed up, some gui tools (IntelliJ) start to bug out and fail to diff properly, and it's easier to just start over.
After ten years of using git, I've more confused by it than ever. People here keep talking about mental models, but I've read a shit ton of docs on it and am still totally confused. Probably some of us just aren't smart enough lol.
Not sure what origin/HEAD is supposed to point to. HEAD is a ref that points to the tip of the current branch. It's not going to be available for remotes (it just doesn't make sense).
To reset the current branch, you need to do two things:
$ git fetch
to fetch commits from the default remote and point remote branches accordingly, and
$ git reset --hard origin/master
to reset HEAD to the remote branch. Substitute master for any other remote branch if you wish.
That's it. I don't know if this is more difficult than re-cloning from scratch (especially if you're doing frontend and then have to reinstall node_modules and such…)
I don't know what the difference is, honestly :( I believe you, but I see both online and nobody seems to know the difference and it seems to work. Shrug? Most of my git life is copy pasting somebody else's commands because the model of it is really too complex for me. I've given up on caring... it's easier and faster to rewrite some code than deal with git's commands.
Same thing for node modules, lol. Delete the folder and try again. If that still doesn't work, delete the lock file and try again.
It's a terrible practice, I know, but it's the only thing that actually seems to work in my experience.
EDIT: Apparently origin/master points to a specific branch. origin/HEAD points to the top of the "default" remote branch, which is often, but not always, master. Or something like that. I don't know for sure.
Two things to make sense of how origin/HEAD is working.
First is that HEAD always points to the commit that you currently have checked out. So, for example, if you have the master branch checked out, HEAD will be whatever is the latest commit in master in your local copy of the repository.
Second is that to git there is no difference between the originating repository and your own. If you had your copy of the repo fully exposed, the remote machine that you cloned it from could push changes to your copy exactly the same way that you push changes to the remote machine.
That second part is important because it means that the remote machine you're pulling from also has its own HEAD pointer. When you reset your state to origin/HEAD, you're telling git to set your own HEAD to point to the same thing as the remote machine's HEAD. This is very likely to be the same asking it to reset to origin/master because HEAD is probably pointing to master on the remote machine.
The reason it's likely that HEAD=master is that in most circumstances the repo on the remote machine isn't manually being touched. When you first setup a repo there is only a single branch so that is what HEAD points to. If no one ever logs into the machine and executes a checkout command, that's what the server is going to continue to point to.
However since there's no guarantee that HEAD=master, you shouldn't rely on that and instead always use the actual branch name.
Thank you, that clears it up! And probably explains why I've lost work when resetting other branches; I wanted to revert to the latest remote tip of their branch, not reset that branch to master, but I screwed up because of HEAD. Thank you for clarifying!
But that doesn't work if you rewrote history in some way (I'm not sure why that's even possible). In that case your local git can get pretty messed up, some gui tools (IntelliJ) start to bug out and fail to diff properly, and it's easier to just start over.
After ten years of using git, I've more confused by it than ever. People here keep talking about mental models, but I've read a shit ton of docs on it and am still totally confused. Probably some of us just aren't smart enough lol.