Troubleshooting — Stage 4: Try a Branch

Common Errors

fatal: A branch named 'dark-theme' already exists

Cause: You already created the branch (maybe in an earlier attempt) and are trying to create it again.

Fix: Just switch to it: git checkout dark-theme. Or delete and recreate: git branch -D dark-theme && git checkout -b dark-theme.

error: Your local changes to the following files would be overwritten by checkout

Cause: You have uncommitted changes and Git is protecting them. Switching branches could destroy those changes.

Fix: Either commit the changes first (git add . && git commit -m "...") or temporarily stash them (git stash). You can restore stashed changes later with git stash pop.

I created the branch on the wrong commit

Cause: You ran git checkout -b dark-theme before finishing Stage 3, so the new branch is rooted somewhere earlier in the history.

Fix: Delete and recreate: git checkout main, git branch -D dark-theme, then make sure git log --oneline on main shows all three commits. Now run git checkout -b dark-theme.

FAQ

Do I have to name it dark-theme?

For this tutorial, yes — so the rest of the instructions make sense. In real projects, branch names follow your team's convention. Common patterns are feature/foo, fix/bar, or just a short word.

Is there a difference between git checkout -b and git switch -c?

No, they do the same thing for creating and switching to a branch. git switch is a newer command introduced to separate "switch branches" from the many other things git checkout can do. Both work.

Can two people have branches with the same name?

Yes — branches are local until you push them. We cover pushing in Stage 8. For now, your dark-theme lives only on your computer.

Why does the tutorial check out a branch if nothing changes?

Because the concept is subtle. If you immediately made a visible change, you would conflate "creating a branch" with "committing on a branch." Splitting them into two stages makes each idea stand on its own.